CISCO-ENHANCED-SLB-MIB

SnmpAdminStringAn octet string containing administrative information, preferably in human-readable form. To facilitate internationalization, this information is represented using the ISO/IEC IS 10646-1 character set, encoded as an octet string using the UTF-8 transformation format described in [RFC2279]. Since additional code points are added by amendments to the 10646 standard from time to time, implementations must be prepared to encounter any code point from 0x00000000 to 0x7fffffff. Byte sequences that do not correspond to the valid UTF-8 encoding of a code point or are outside this range are prohibited. The use of control codes should be avoided. When it is necessary to represent a newline, the control code sequence CR LF should be used. The use of leading or trailing white space should be avoided. For code points not directly supported by user interface hardware or software, an alternative means of entry and display, such as hexadecimal, may be provided. For information encoded in 7-bit US-ASCII, the UTF-8 encoding is identical to the US-ASCII encoding. UTF-8 may require multiple bytes to represent a single character / code point; thus the length of this object in octets may be different from the number of characters encoded. Similarly, size constraints refer to the number of encoded octets, not the number of characters represented by an encoding. Note that when this TC is used for an object that is used or envisioned to be used as an index, then a SIZE restriction MUST be specified so that the number of sub-identifiers for any object instance does not exceed the limit of 128, as defined by [RFC3416]. Note that the size of an SnmpAdminString object is measured in octets, not characters. SIZE (1..255) · OCTET STRING · hint 255t

This object identifies the name(unique identifier) of the real server.

INTEGER1 = redirect2 = host · Integer32

The type of the real server. The possible values are : redirect(1): Specifies that this real server is just used for redirecting traffic to new virtual server equivalent pointed to by the redirection string (cesRserverRedirectRelocationStr). host (2): Specifies typical server offering services. The real server type redirect(1) implies that the following objects are applicable for a real server entry: cesRserverRedirectRelocationStr. cesRserverRedirectCode. cesRserverRedirectPort. This means that only the above objects will be used to create the real server entry, and all other objects will be ignored during row creation. The real server type host(2) implies that the following objects are applicable for a real server entry: cesRserverIpAddressType cesRserverIpAddress This means that only the above objects will be used to create the real server entry, and all other objects will be ignored during row creation. This object cannot be changed when the cesRserverRowStatus value is 'active'.

InetAddressType0 = unknown1 = ipv42 = ipv63 = ipv4z4 = ipv6z16 = dnsA value that represents a type of Internet address. unknown(0) An unknown address type. This value MUST be used if the value of the corresponding InetAddress object is a zero-length string. It may also be used to indicate an IP address that is not in one of the formats defined below. ipv4(1) An IPv4 address as defined by the InetAddressIPv4 textual convention. ipv6(2) An IPv6 address as defined by the InetAddressIPv6 textual convention. ipv4z(3) A non-global IPv4 address including a zone index as defined by the InetAddressIPv4z textual convention. ipv6z(4) A non-global IPv6 address including a zone index as defined by the InetAddressIPv6z textual convention. dns(16) A DNS domain name as defined by the InetAddressDNS textual convention. Each definition of a concrete InetAddressType value must be accompanied by a definition of a textual convention for use with that InetAddressType. To support future extensions, the InetAddressType textual convention SHOULD NOT be sub-typed in object type definitions. It MAY be sub-typed in compliance statements in order to require only a subset of these address types for a compliant implementation. Implementations must ensure that InetAddressType objects and any dependent objects (e.g., InetAddress objects) are consistent. An inconsistentValue error must be generated if an attempt to change an InetAddressType object would, for example, lead to an undefined InetAddress value. In particular, InetAddressType/InetAddress pairs must be changed together if the address type changes (e.g., from ipv6(2) to ipv4(1)). · Integer32

The type of the internet Address configured in 'cesRserverIpAddress'. This object is applicable only for cesRserverType value 'host'.

InetAddressDenotes a generic Internet address. An InetAddress value is always interpreted within the context of an InetAddressType value. Every usage of the InetAddress textual convention is required to specify the InetAddressType object that provides the context. It is suggested that the InetAddressType object be logically registered before the object(s) that use the InetAddress textual convention, if they appear in the same logical row. The value of an InetAddress object must always be consistent with the value of the associated InetAddressType object. Attempts to set an InetAddress object to a value inconsistent with the associated InetAddressType must fail with an inconsistentValue error. When this textual convention is used as the syntax of an index object, there may be issues with the limit of 128 sub-identifiers specified in SMIv2, STD 58. In this case, the object definition MUST include a 'SIZE' clause to limit the number of potential instance sub-identifiers; otherwise the applicable constraints MUST be stated in the appropriate conceptual row DESCRIPTION clauses, or in the surrounding documentation if there is no single DESCRIPTION clause that is appropriate. SIZE (0..255) · OCTET STRING

This object specifies the internet address of real server. This object is applicable only for cesRserverType value 'host'. This object contains zero length octet string for cesRserverType value other than 'host'.

SnmpAdminStringAn octet string containing administrative information, preferably in human-readable form. To facilitate internationalization, this information is represented using the ISO/IEC IS 10646-1 character set, encoded as an octet string using the UTF-8 transformation format described in [RFC2279]. Since additional code points are added by amendments to the 10646 standard from time to time, implementations must be prepared to encounter any code point from 0x00000000 to 0x7fffffff. Byte sequences that do not correspond to the valid UTF-8 encoding of a code point or are outside this range are prohibited. The use of control codes should be avoided. When it is necessary to represent a newline, the control code sequence CR LF should be used. The use of leading or trailing white space should be avoided. For code points not directly supported by user interface hardware or software, an alternative means of entry and display, such as hexadecimal, may be provided. For information encoded in 7-bit US-ASCII, the UTF-8 encoding is identical to the US-ASCII encoding. UTF-8 may require multiple bytes to represent a single character / code point; thus the length of this object in octets may be different from the number of characters encoded. Similarly, size constraints refer to the number of encoded octets, not the number of characters represented by an encoding. Note that when this TC is used for an object that is used or envisioned to be used as an index, then a SIZE restriction MUST be specified so that the number of sub-identifiers for any object instance does not exceed the limit of 128, as defined by [RFC3416]. Note that the size of an SnmpAdminString object is measured in octets, not characters. SIZE (0..255) · OCTET STRING · hint 255t

This object is used for configuring the description of the real server.

Unsigned32

This object is used for configuring the maximum number of concurrent active connections this real server can handle.

Unsigned32

This object is used for configuring the minimum number of concurrent active connections this real server can handle. The value for this object must to be less than or equal to value specified in cesRserverMaxConns object.

Unsigned32 (0..65535)

The user configured weight of the real server for the load-balancing algorithms. This is applicable only in case of weighted Round Robin Predictor algorithms (SlbPredictor values: 'roundRobin', 'leastConns'). A weight of zero indicates that no new connections will be assigned to this real server. Higher weight values indicate to the load-balancing algorithms a higher availability of this real server to accept more work. This object is applicable only for cesRserverType value 'host'.

SlbUrlStringThe octet string containing the Uniform Resource Locator (URL) information. It is in human-readable form. SIZE (0..255) · OCTET STRING · hint 255a

The relocation URL string used for redirection. This value is sent in the reply of the Redirect Server. This object is applicable only for cesRserverType value 'redirect'.

CiscoHTTPResponseStatusCodeThis corresponds to the HTTP Status code. The Status-Code element in HTTP response is a 3-digit integer result code of the attempt to understand and satisfy the HTTP request The Status-Code is intended for use by automata. The first digit of the Status-Code defines the class of response. The last two digits do not have any categorization role. There are 5 values for the first digit: - 1xx: Informational - Request received, continuing process - 2xx: Success - The action was successfully received, understood, and accepted - 3xx: Redirection - Further action must be taken in order to complete the request - 4xx: Client Error - The request contains bad syntax or cannot be fulfilled - 5xx: Server Error - The server failed to fulfill an apparently valid request.Reference: RFC 2616 Section 6.1.1 Status Code and Reason Phrase. (300..399) · Unsigned32

Reference: RFC 2616 Section 6.1.1 Status Code and Reason Phrase. RFC 2616 Section 10.3 Redirection 3xxx.

The HTTP response code sent in the reply by the redirect server. meaning of few Redirect Codes: 301 : If page is permanently moved. The requested resource has been assigned a new permanent URL. 302 : The requested resource resides temporarily under a different URL. This object is applicable only for cesRserverType value 'redirect'.

InetPortNumberRepresents a 16 bit port number of an Internet transport layer protocol. Port numbers are assigned by IANA. A current list of all assignments is available from <http://www.iana.org/>. The value zero is object-specific and must be defined as part of the description of any object that uses this syntax. Examples of the usage of zero might include situations where a port number is unknown, or when the value zero is used as a wildcard in a filter.Reference: STD 6 (RFC 768), STD 7 (RFC 793) and RFC 2960 (0..65535) · Unsigned32 · hint d

The TCP or UDP port of redirect server. This is used for redirecting the URL string identified by 'cesRserverRedirectRelocationStr'. This object is applicable only for cesRserverType = 'redirect'.

CiscoRserverAdminStatus1 = inService2 = outOfService3 = inServiceStandbyThis is the textual convention for administrative status of the real server. The possible value(s) are : 'inService' : Places the real server into service state. 'outOfService' : Places the real server out of service. 'inserviceStandby' : Places the real server into standby state. · Integer32

This is used for setting the administrative status of the Real server. If set to 'inService', the real server is placed into service. If set to 'outOfService' the real server is taken out of service.

SlbRealServerState1 = outOfService2 = inService3 = failed4 = readyToTest5 = testing6 = maxConnsThrottle7 = maxClientsThrottle8 = dfpThrottle9 = probeFailed10 = probeTesting11 = operWait12 = testWait13 = inbandProbeFailed14 = returnCodeFailed15 = arpFailed16 = standby17 = inactive18 = maxLoadThe server state represents the state of a real server being load-balanced by SLB. 'outOfService' : Server is not in use by SLB as a destination for client connections. This state can be written and read. 'inService' : Server is in use as a destination for SLB client connections. This state can be written and read. 'failed' : Server has failed and will not be retried for retry timer seconds. This state can only be read. 'readyToTest' : Server has failed and has an expired retry timer, test connections will begin flow to it soon. This state can only be read. 'testing' : Server has failed and been given another test connection, success of this connection is not known yet. This state can only be read. 'maxConnsThrottle' : Server has reached its maximum number of connections and is no longer being given connections. This state can only be read. 'maxClientsThrottle': Server has reached the maximum allowed clients. This state can only be read. 'dfpThrottle' : DFP has lowered the weight of this server to throttle level, so that no new connections will be assigned to it until DFP raises its weight. This state can only be read. 'probeFailed' : SLB probe to this this server has failed. No new connections will be assigned to it until a probe to this server succeeds. This state can only be read. 'probeTesting' : Server has received a test probe from SLB. This state can only be read. 'operWait' : Server is ready to go operational, but is waiting for the associated redirect virtual to be inservice. This state can only be read. 'testWait' : Server is ready to be tested. This state is applicable only when the server is used for http redirect load balancing. This state can only be read. 'inbandProbeFailed': Server has failed the inband Health Probe agent. This state can only be read. 'returnCodeFailed' : Server has been disabled because it returned an HTTP code that matched a configured value. This state can only be read. 'arpFailed' : ARP request to this server has failed. This state can only be read. 'standby' : Server is in standby state. No connections will be assigned to it, unless the primary server fails. This state can be written and read. 'inactive' : Server is disabled as it has become inactive such as in the case when the real server is not associated to any server farm.This state can only be read. 'maxLoad' : Server is disabled as it hit max-load. This state can only be read. · Integer32

This object provides the current state of the real server.

SnmpAdminStringAn octet string containing administrative information, preferably in human-readable form. To facilitate internationalization, this information is represented using the ISO/IEC IS 10646-1 character set, encoded as an octet string using the UTF-8 transformation format described in [RFC2279]. Since additional code points are added by amendments to the 10646 standard from time to time, implementations must be prepared to encounter any code point from 0x00000000 to 0x7fffffff. Byte sequences that do not correspond to the valid UTF-8 encoding of a code point or are outside this range are prohibited. The use of control codes should be avoided. When it is necessary to represent a newline, the control code sequence CR LF should be used. The use of leading or trailing white space should be avoided. For code points not directly supported by user interface hardware or software, an alternative means of entry and display, such as hexadecimal, may be provided. For information encoded in 7-bit US-ASCII, the UTF-8 encoding is identical to the US-ASCII encoding. UTF-8 may require multiple bytes to represent a single character / code point; thus the length of this object in octets may be different from the number of characters encoded. Similarly, size constraints refer to the number of encoded octets, not the number of characters represented by an encoding. Note that when this TC is used for an object that is used or envisioned to be used as an index, then a SIZE restriction MUST be specified so that the number of sub-identifiers for any object instance does not exceed the limit of 128, as defined by [RFC3416]. Note that the size of an SnmpAdminString object is measured in octets, not characters. SIZE (0..255) · OCTET STRING · hint 255t

This object contains the descriptive text qualifying the reason for the value in cesRserverOperStatus. Examples: ARP failure Health probe failed.

StorageType1 = other2 = volatile3 = nonVolatile4 = permanent5 = readOnlyDescribes the memory realization of a conceptual row. A row which is volatile(2) is lost upon reboot. A row which is either nonVolatile(3), permanent(4) or readOnly(5), is backed up by stable storage. A row which is permanent(4) can be changed but not deleted. A row which is readOnly(5) cannot be changed nor deleted. If the value of an object with this syntax is either permanent(4) or readOnly(5), it cannot be written. Conversely, if the value is either other(1), volatile(2) or nonVolatile(3), it cannot be modified to be permanent(4) or readOnly(5). (All illegal modifications result in a 'wrongValue' error.) Every usage of this textual convention is required to specify the columnar objects which a permanent(4) row must at a minimum allow to be writable. · Integer32

The storage type for this conceptual row.

RowStatus1 = active2 = notInService3 = notReady4 = createAndGo5 = createAndWait6 = destroyThe RowStatus textual convention is used to manage the creation and deletion of conceptual rows, and is used as the value of the SYNTAX clause for the status column of a conceptual row (as described in Section 7.7.1 of [2].) The status column has six defined values: - `active', which indicates that the conceptual row is available for use by the managed device; - `notInService', which indicates that the conceptual row exists in the agent, but is unavailable for use by the managed device (see NOTE below); 'notInService' has no implication regarding the internal consistency of the row, availability of resources, or consistency with the current state of the managed device; - `notReady', which indicates that the conceptual row exists in the agent, but is missing information necessary in order to be available for use by the managed device (i.e., one or more required columns in the conceptual row have not been instanciated); - `createAndGo', which is supplied by a management station wishing to create a new instance of a conceptual row and to have its status automatically set to active, making it available for use by the managed device; - `createAndWait', which is supplied by a management station wishing to create a new instance of a conceptual row (but not make it available for use by the managed device); and, - `destroy', which is supplied by a management station wishing to delete all of the instances associated with an existing conceptual row. Whereas five of the six values (all except `notReady') may be specified in a management protocol set operation, only three values will be returned in response to a management protocol retrieval operation: `notReady', `notInService' or `active'. That is, when queried, an existing conceptual row has only three states: it is either available for use by the managed device (the status column has value `active'); it is not available for use by the managed device, though the agent has sufficient information to attempt to make it so (the status column has value `notInService'); or, it is not available for use by the managed device, and an attempt to make it so would fail because the agent has insufficient information (the state column has value `notReady'). NOTE WELL This textual convention may be used for a MIB table, irrespective of whether the values of that table's conceptual rows are able to be modified while it is active, or whether its conceptual rows must be taken out of service in order to be modified. That is, it is the responsibility of the DESCRIPTION clause of the status column to specify whether the status column must not be `active' in order for the value of some other column of the same conceptual row to be modified. If such a specification is made, affected columns may be changed by an SNMP set PDU if the RowStatus would not be equal to `active' either immediately before or after processing the PDU. In other words, if the PDU also contained a varbind that would change the RowStatus value, the column in question may be changed if the RowStatus was not equal to `active' as the PDU was received, or if the varbind sets the status to a value other than 'active'. Also note that whenever any elements of a row exist, the RowStatus column must also exist. To summarize the effect of having a conceptual row with a status column having a SYNTAX clause value of RowStatus, consider the following state diagram: STATE +--------------+-----------+-------------+------------- | A | B | C | D | |status col.|status column| |status column | is | is |status column ACTION |does not exist| notReady | notInService| is active --------------+--------------+-----------+-------------+------------- set status |noError ->D|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndGo |inconsistent- | | | | Value| | | --------------+--------------+-----------+-------------+------------- set status |noError see 1|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndWait |wrongValue | | | --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError column to | Value| entValue| | active | | | | | | or | | | | | | | |see 2 ->D|see 8 ->D| ->D --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError ->C column to | Value| entValue| | notInService | | | | | | or | | or | | | | | |see 3 ->C| ->C|see 6 --------------+--------------+-----------+-------------+------------- set status |noError |noError |noError |noError ->A column to | | | | or destroy | ->A| ->A| ->A|see 7 --------------+--------------+-----------+-------------+------------- set any other |see 4 |noError |noError |see 5 column to some| | | | value | | see 1| ->C| ->D --------------+--------------+-----------+-------------+------------- (1) goto B or C, depending on information available to the agent. (2) if other variable bindings included in the same PDU, provide values for all columns which are missing but required, and all columns have acceptable values, then return noError and goto D. (3) if other variable bindings included in the same PDU, provide legal values for all columns which are missing but required, then return noError and goto C. (4) at the discretion of the agent, the return value may be either: inconsistentName: because the agent does not choose to create such an instance when the corresponding RowStatus instance does not exist, or inconsistentValue: if the supplied value is inconsistent with the state of some other MIB object's value, or noError: because the agent chooses to create the instance. If noError is returned, then the instance of the status column must also be created, and the new state is B or C, depending on the information available to the agent. If inconsistentName or inconsistentValue is returned, the row remains in state A. (5) depending on the MIB definition for the column/table, either noError or inconsistentValue may be returned. (6) the return value can indicate one of the following errors: wrongValue: because the agent does not support notInService (e.g., an agent which does not support createAndWait), or inconsistentValue: because the agent is unable to take the row out of service at this time, perhaps because it is in use and cannot be de-activated. (7) the return value can indicate the following error: inconsistentValue: because the agent is unable to remove the row at this time, perhaps because it is in use and cannot be de-activated. (8) the transition to D can fail, e.g., if the values of the conceptual row are inconsistent, then the error code would be inconsistentValue. NOTE: Other processing of (this and other varbinds of) the set request may result in a response other than noError being returned, e.g., wrongValue, noCreation, etc. Conceptual Row Creation There are four potential interactions when creating a conceptual row: selecting an instance-identifier which is not in use; creating the conceptual row; initializing any objects for which the agent does not supply a default; and, making the conceptual row available for use by the managed device. Interaction 1: Selecting an Instance-Identifier The algorithm used to select an instance-identifier varies for each conceptual row. In some cases, the instance- identifier is semantically significant, e.g., the destination address of a route, and a management station selects the instance-identifier according to the semantics. In other cases, the instance-identifier is used solely to distinguish conceptual rows, and a management station without specific knowledge of the conceptual row might examine the instances present in order to determine an unused instance-identifier. (This approach may be used, but it is often highly sub-optimal; however, it is also a questionable practice for a naive management station to attempt conceptual row creation.) Alternately, the MIB module which defines the conceptual row might provide one or more objects which provide assistance in determining an unused instance-identifier. For example, if the conceptual row is indexed by an integer-value, then an object having an integer-valued SYNTAX clause might be defined for such a purpose, allowing a management station to issue a management protocol retrieval operation. In order to avoid unnecessary collisions between competing management stations, `adjacent' retrievals of this object should be different. Finally, the management station could select a pseudo-random number to use as the index. In the event that this index was already in use and an inconsistentValue was returned in response to the management protocol set operation, the management station should simply select a new pseudo-random number and retry the operation. A MIB designer should choose between the two latter algorithms based on the size of the table (and therefore the efficiency of each algorithm). For tables in which a large number of entries are expected, it is recommended that a MIB object be defined that returns an acceptable index for creation. For tables with small numbers of entries, it is recommended that the latter pseudo-random index mechanism be used. Interaction 2: Creating the Conceptual Row Once an unused instance-identifier has been selected, the management station determines if it wishes to create and activate the conceptual row in one transaction or in a negotiated set of interactions. Interaction 2a: Creating and Activating the Conceptual Row The management station must first determine the column requirements, i.e., it must determine those columns for which it must or must not provide values. Depending on the complexity of the table and the management station's knowledge of the agent's capabilities, this determination can be made locally by the management station. Alternately, the management station issues a management protocol get operation to examine all columns in the conceptual row that it wishes to create. In response, for each column, there are three possible outcomes: - a value is returned, indicating that some other management station has already created this conceptual row. We return to interaction 1. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it should supply a value for this column when the conceptual row is to be created. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. Once the column requirements have been determined, a management protocol set operation is accordingly issued. This operation also sets the new instance of the status column to `createAndGo'. When the agent processes the set operation, it verifies that it has sufficient information to make the conceptual row available for use by the managed device. The information available to the agent is provided by two sources: the management protocol set operation which creates the conceptual row, and, implementation-specific defaults supplied by the agent (note that an agent must provide implementation-specific defaults for at least those objects which it implements as read-only). If there is sufficient information available, then the conceptual row is created, a `noError' response is returned, the status column is set to `active', and no further interactions are necessary (i.e., interactions 3 and 4 are skipped). If there is insufficient information, then the conceptual row is not created, and the set operation fails with an error of `inconsistentValue'. On this error, the management station can issue a management protocol retrieval operation to determine if this was because it failed to specify a value for a required column, or, because the selected instance of the status column already existed. In the latter case, we return to interaction 1. In the former case, the management station can re-issue the set operation with the additional information, or begin interaction 2 again using `createAndWait' in order to negotiate creation of the conceptual row. NOTE WELL Regardless of the method used to determine the column requirements, it is possible that the management station might deem a column necessary when, in fact, the agent will not allow that particular columnar instance to be created or written. In this case, the management protocol set operation will fail with an error such as `noCreation' or `notWritable'. In this case, the management station decides whether it needs to be able to set a value for that particular columnar instance. If not, the management station re-issues the management protocol set operation, but without setting a value for that particular columnar instance; otherwise, the management station aborts the row creation algorithm. Interaction 2b: Negotiating the Creation of the Conceptual Row The management station issues a management protocol set operation which sets the desired instance of the status column to `createAndWait'. If the agent is unwilling to process a request of this sort, the set operation fails with an error of `wrongValue'. (As a consequence, such an agent must be prepared to accept a single management protocol set operation, i.e., interaction 2a above, containing all of the columns indicated by its column requirements.) Otherwise, the conceptual row is created, a `noError' response is returned, and the status column is immediately set to either `notInService' or `notReady', depending on whether it has sufficient information to (attempt to) make the conceptual row available for use by the managed device. If there is sufficient information available, then the status column is set to `notInService'; otherwise, if there is insufficient information, then the status column is set to `notReady'. Regardless, we proceed to interaction 3. Interaction 3: Initializing non-defaulted Objects The management station must now determine the column requirements. It issues a management protocol get operation to examine all columns in the created conceptual row. In the response, for each column, there are three possible outcomes: - a value is returned, indicating that the agent implements the object-type associated with this column and had sufficient information to provide a value. For those columns to which the agent provides read-create access (and for which the agent allows their values to be changed after their creation), a value return tells the management station that it may issue additional management protocol set operations, if it desires, in order to change the value associated with this column. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. However, the agent does not have sufficient information to provide a value, and until a value is provided, the conceptual row may not be made available for use by the managed device. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it must issue additional management protocol set operations, in order to provide a value associated with this column. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. If the value associated with the status column is `notReady', then the management station must first deal with all `noSuchInstance' columns, if any. Having done so, the value of the status column becomes `notInService', and we proceed to interaction 4. Interaction 4: Making the Conceptual Row Available Once the management station is satisfied with the values associated with the columns of the conceptual row, it issues a management protocol set operation to set the status column to `active'. If the agent has sufficient information to make the conceptual row available for use by the managed device, the management protocol set operation succeeds (a `noError' response is returned). Otherwise, the management protocol set operation fails with an error of `inconsistentValue'. NOTE WELL A conceptual row having a status column with value `notInService' or `notReady' is unavailable to the managed device. As such, it is possible for the managed device to create its own instances during the time between the management protocol set operation which sets the status column to `createAndWait' and the management protocol set operation which sets the status column to `active'. In this case, when the management protocol set operation is issued to set the status column to `active', the values held in the agent supersede those used by the managed device. If the management station is prevented from setting the status column to `active' (e.g., due to management station or network failure) the conceptual row will be left in the `notInService' or `notReady' state, consuming resources indefinitely. The agent must detect conceptual rows that have been in either state for an abnormally long period of time and remove them. It is the responsibility of the DESCRIPTION clause of the status column to indicate what an abnormally long period of time would be. This period of time should be long enough to allow for human response time (including `think time') between the creation of the conceptual row and the setting of the status to `active'. In the absence of such information in the DESCRIPTION clause, it is suggested that this period be approximately 5 minutes in length. This removal action applies not only to newly-created rows, but also to previously active rows which are set to, and left in, the notInService state for a prolonged period exceeding that which is considered normal for such a conceptual row. Conceptual Row Suspension When a conceptual row is `active', the management station may issue a management protocol set operation which sets the instance of the status column to `notInService'. If the agent is unwilling to do so, the set operation fails with an error of `wrongValue' or `inconsistentValue'. Otherwise, the conceptual row is taken out of service, and a `noError' response is returned. It is the responsibility of the DESCRIPTION clause of the status column to indicate under what circumstances the status column should be taken out of service (e.g., in order for the value of some other column of the same conceptual row to be modified). Conceptual Row Deletion For deletion of conceptual rows, a management protocol set operation is issued which sets the instance of the status column to `destroy'. This request may be made regardless of the current value of the status column (e.g., it is possible to delete conceptual rows which are either `notReady', `notInService' or `active'.) If the operation succeeds, then all instances associated with the conceptual row are immediately removed. · Integer32

The object is used for adding/deleting entries in the table. An entry MUST NOT exist in the active state unless all objects in the entry have an appropriate value, as described in the description clause for each writeable object. This object may be modified if the associated instance of this object is equal to active(1), notInService(2), or notReady(3). All other writeable objects may be modified if the associated instance of this object is equal to notInService(2) or notReady(3). This object may not be set to 'destroy' if the real server identified by cesRserverName is referenced and being used in other tables.

Counter64 (0..18446744073709551615) · connections

The total number of connections loadbalanced to this real server.

Counter64 (0..18446744073709551615) · connections

The total number of failed attempts to establish a connection to the real server.

Counter64 (0..18446744073709551615) · connections

The total number of active connections loadbalanced to this real server.

SlbRserverLocalityState1 = unknown2 = local3 = remoteThis is the textual convention for locality status of the real server. The possible value(s) are : 'unknown' : The locality of the real server is not known. 'local' : The locality of the real server is local. 'remote' : The locality of the real server is remote. state. · Integer32

This object indicates the current locality state of the real server.

SlbServerStringThe configured name associated with an SLB object. SIZE (1..96) · OCTET STRING

Reference: cslbxProbeCfgTable defined in CISCO-SLB-HEALTH-MON-MIB

The name of the health probe configured in a Rserver. This value must correspond to an entry in cslbxProbeCfgTable.

StorageType1 = other2 = volatile3 = nonVolatile4 = permanent5 = readOnlyDescribes the memory realization of a conceptual row. A row which is volatile(2) is lost upon reboot. A row which is either nonVolatile(3), permanent(4) or readOnly(5), is backed up by stable storage. A row which is permanent(4) can be changed but not deleted. A row which is readOnly(5) cannot be changed nor deleted. If the value of an object with this syntax is either permanent(4) or readOnly(5), it cannot be written. Conversely, if the value is either other(1), volatile(2) or nonVolatile(3), it cannot be modified to be permanent(4) or readOnly(5). (All illegal modifications result in a 'wrongValue' error.) Every usage of this textual convention is required to specify the columnar objects which a permanent(4) row must at a minimum allow to be writable. · Integer32

The storage type for this conceptual row.

RowStatus1 = active2 = notInService3 = notReady4 = createAndGo5 = createAndWait6 = destroyThe RowStatus textual convention is used to manage the creation and deletion of conceptual rows, and is used as the value of the SYNTAX clause for the status column of a conceptual row (as described in Section 7.7.1 of [2].) The status column has six defined values: - `active', which indicates that the conceptual row is available for use by the managed device; - `notInService', which indicates that the conceptual row exists in the agent, but is unavailable for use by the managed device (see NOTE below); 'notInService' has no implication regarding the internal consistency of the row, availability of resources, or consistency with the current state of the managed device; - `notReady', which indicates that the conceptual row exists in the agent, but is missing information necessary in order to be available for use by the managed device (i.e., one or more required columns in the conceptual row have not been instanciated); - `createAndGo', which is supplied by a management station wishing to create a new instance of a conceptual row and to have its status automatically set to active, making it available for use by the managed device; - `createAndWait', which is supplied by a management station wishing to create a new instance of a conceptual row (but not make it available for use by the managed device); and, - `destroy', which is supplied by a management station wishing to delete all of the instances associated with an existing conceptual row. Whereas five of the six values (all except `notReady') may be specified in a management protocol set operation, only three values will be returned in response to a management protocol retrieval operation: `notReady', `notInService' or `active'. That is, when queried, an existing conceptual row has only three states: it is either available for use by the managed device (the status column has value `active'); it is not available for use by the managed device, though the agent has sufficient information to attempt to make it so (the status column has value `notInService'); or, it is not available for use by the managed device, and an attempt to make it so would fail because the agent has insufficient information (the state column has value `notReady'). NOTE WELL This textual convention may be used for a MIB table, irrespective of whether the values of that table's conceptual rows are able to be modified while it is active, or whether its conceptual rows must be taken out of service in order to be modified. That is, it is the responsibility of the DESCRIPTION clause of the status column to specify whether the status column must not be `active' in order for the value of some other column of the same conceptual row to be modified. If such a specification is made, affected columns may be changed by an SNMP set PDU if the RowStatus would not be equal to `active' either immediately before or after processing the PDU. In other words, if the PDU also contained a varbind that would change the RowStatus value, the column in question may be changed if the RowStatus was not equal to `active' as the PDU was received, or if the varbind sets the status to a value other than 'active'. Also note that whenever any elements of a row exist, the RowStatus column must also exist. To summarize the effect of having a conceptual row with a status column having a SYNTAX clause value of RowStatus, consider the following state diagram: STATE +--------------+-----------+-------------+------------- | A | B | C | D | |status col.|status column| |status column | is | is |status column ACTION |does not exist| notReady | notInService| is active --------------+--------------+-----------+-------------+------------- set status |noError ->D|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndGo |inconsistent- | | | | Value| | | --------------+--------------+-----------+-------------+------------- set status |noError see 1|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndWait |wrongValue | | | --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError column to | Value| entValue| | active | | | | | | or | | | | | | | |see 2 ->D|see 8 ->D| ->D --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError ->C column to | Value| entValue| | notInService | | | | | | or | | or | | | | | |see 3 ->C| ->C|see 6 --------------+--------------+-----------+-------------+------------- set status |noError |noError |noError |noError ->A column to | | | | or destroy | ->A| ->A| ->A|see 7 --------------+--------------+-----------+-------------+------------- set any other |see 4 |noError |noError |see 5 column to some| | | | value | | see 1| ->C| ->D --------------+--------------+-----------+-------------+------------- (1) goto B or C, depending on information available to the agent. (2) if other variable bindings included in the same PDU, provide values for all columns which are missing but required, and all columns have acceptable values, then return noError and goto D. (3) if other variable bindings included in the same PDU, provide legal values for all columns which are missing but required, then return noError and goto C. (4) at the discretion of the agent, the return value may be either: inconsistentName: because the agent does not choose to create such an instance when the corresponding RowStatus instance does not exist, or inconsistentValue: if the supplied value is inconsistent with the state of some other MIB object's value, or noError: because the agent chooses to create the instance. If noError is returned, then the instance of the status column must also be created, and the new state is B or C, depending on the information available to the agent. If inconsistentName or inconsistentValue is returned, the row remains in state A. (5) depending on the MIB definition for the column/table, either noError or inconsistentValue may be returned. (6) the return value can indicate one of the following errors: wrongValue: because the agent does not support notInService (e.g., an agent which does not support createAndWait), or inconsistentValue: because the agent is unable to take the row out of service at this time, perhaps because it is in use and cannot be de-activated. (7) the return value can indicate the following error: inconsistentValue: because the agent is unable to remove the row at this time, perhaps because it is in use and cannot be de-activated. (8) the transition to D can fail, e.g., if the values of the conceptual row are inconsistent, then the error code would be inconsistentValue. NOTE: Other processing of (this and other varbinds of) the set request may result in a response other than noError being returned, e.g., wrongValue, noCreation, etc. Conceptual Row Creation There are four potential interactions when creating a conceptual row: selecting an instance-identifier which is not in use; creating the conceptual row; initializing any objects for which the agent does not supply a default; and, making the conceptual row available for use by the managed device. Interaction 1: Selecting an Instance-Identifier The algorithm used to select an instance-identifier varies for each conceptual row. In some cases, the instance- identifier is semantically significant, e.g., the destination address of a route, and a management station selects the instance-identifier according to the semantics. In other cases, the instance-identifier is used solely to distinguish conceptual rows, and a management station without specific knowledge of the conceptual row might examine the instances present in order to determine an unused instance-identifier. (This approach may be used, but it is often highly sub-optimal; however, it is also a questionable practice for a naive management station to attempt conceptual row creation.) Alternately, the MIB module which defines the conceptual row might provide one or more objects which provide assistance in determining an unused instance-identifier. For example, if the conceptual row is indexed by an integer-value, then an object having an integer-valued SYNTAX clause might be defined for such a purpose, allowing a management station to issue a management protocol retrieval operation. In order to avoid unnecessary collisions between competing management stations, `adjacent' retrievals of this object should be different. Finally, the management station could select a pseudo-random number to use as the index. In the event that this index was already in use and an inconsistentValue was returned in response to the management protocol set operation, the management station should simply select a new pseudo-random number and retry the operation. A MIB designer should choose between the two latter algorithms based on the size of the table (and therefore the efficiency of each algorithm). For tables in which a large number of entries are expected, it is recommended that a MIB object be defined that returns an acceptable index for creation. For tables with small numbers of entries, it is recommended that the latter pseudo-random index mechanism be used. Interaction 2: Creating the Conceptual Row Once an unused instance-identifier has been selected, the management station determines if it wishes to create and activate the conceptual row in one transaction or in a negotiated set of interactions. Interaction 2a: Creating and Activating the Conceptual Row The management station must first determine the column requirements, i.e., it must determine those columns for which it must or must not provide values. Depending on the complexity of the table and the management station's knowledge of the agent's capabilities, this determination can be made locally by the management station. Alternately, the management station issues a management protocol get operation to examine all columns in the conceptual row that it wishes to create. In response, for each column, there are three possible outcomes: - a value is returned, indicating that some other management station has already created this conceptual row. We return to interaction 1. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it should supply a value for this column when the conceptual row is to be created. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. Once the column requirements have been determined, a management protocol set operation is accordingly issued. This operation also sets the new instance of the status column to `createAndGo'. When the agent processes the set operation, it verifies that it has sufficient information to make the conceptual row available for use by the managed device. The information available to the agent is provided by two sources: the management protocol set operation which creates the conceptual row, and, implementation-specific defaults supplied by the agent (note that an agent must provide implementation-specific defaults for at least those objects which it implements as read-only). If there is sufficient information available, then the conceptual row is created, a `noError' response is returned, the status column is set to `active', and no further interactions are necessary (i.e., interactions 3 and 4 are skipped). If there is insufficient information, then the conceptual row is not created, and the set operation fails with an error of `inconsistentValue'. On this error, the management station can issue a management protocol retrieval operation to determine if this was because it failed to specify a value for a required column, or, because the selected instance of the status column already existed. In the latter case, we return to interaction 1. In the former case, the management station can re-issue the set operation with the additional information, or begin interaction 2 again using `createAndWait' in order to negotiate creation of the conceptual row. NOTE WELL Regardless of the method used to determine the column requirements, it is possible that the management station might deem a column necessary when, in fact, the agent will not allow that particular columnar instance to be created or written. In this case, the management protocol set operation will fail with an error such as `noCreation' or `notWritable'. In this case, the management station decides whether it needs to be able to set a value for that particular columnar instance. If not, the management station re-issues the management protocol set operation, but without setting a value for that particular columnar instance; otherwise, the management station aborts the row creation algorithm. Interaction 2b: Negotiating the Creation of the Conceptual Row The management station issues a management protocol set operation which sets the desired instance of the status column to `createAndWait'. If the agent is unwilling to process a request of this sort, the set operation fails with an error of `wrongValue'. (As a consequence, such an agent must be prepared to accept a single management protocol set operation, i.e., interaction 2a above, containing all of the columns indicated by its column requirements.) Otherwise, the conceptual row is created, a `noError' response is returned, and the status column is immediately set to either `notInService' or `notReady', depending on whether it has sufficient information to (attempt to) make the conceptual row available for use by the managed device. If there is sufficient information available, then the status column is set to `notInService'; otherwise, if there is insufficient information, then the status column is set to `notReady'. Regardless, we proceed to interaction 3. Interaction 3: Initializing non-defaulted Objects The management station must now determine the column requirements. It issues a management protocol get operation to examine all columns in the created conceptual row. In the response, for each column, there are three possible outcomes: - a value is returned, indicating that the agent implements the object-type associated with this column and had sufficient information to provide a value. For those columns to which the agent provides read-create access (and for which the agent allows their values to be changed after their creation), a value return tells the management station that it may issue additional management protocol set operations, if it desires, in order to change the value associated with this column. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. However, the agent does not have sufficient information to provide a value, and until a value is provided, the conceptual row may not be made available for use by the managed device. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it must issue additional management protocol set operations, in order to provide a value associated with this column. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. If the value associated with the status column is `notReady', then the management station must first deal with all `noSuchInstance' columns, if any. Having done so, the value of the status column becomes `notInService', and we proceed to interaction 4. Interaction 4: Making the Conceptual Row Available Once the management station is satisfied with the values associated with the columns of the conceptual row, it issues a management protocol set operation to set the status column to `active'. If the agent has sufficient information to make the conceptual row available for use by the managed device, the management protocol set operation succeeds (a `noError' response is returned). Otherwise, the management protocol set operation fails with an error of `inconsistentValue'. NOTE WELL A conceptual row having a status column with value `notInService' or `notReady' is unavailable to the managed device. As such, it is possible for the managed device to create its own instances during the time between the management protocol set operation which sets the status column to `createAndWait' and the management protocol set operation which sets the status column to `active'. In this case, when the management protocol set operation is issued to set the status column to `active', the values held in the agent supersede those used by the managed device. If the management station is prevented from setting the status column to `active' (e.g., due to management station or network failure) the conceptual row will be left in the `notInService' or `notReady' state, consuming resources indefinitely. The agent must detect conceptual rows that have been in either state for an abnormally long period of time and remove them. It is the responsibility of the DESCRIPTION clause of the status column to indicate what an abnormally long period of time would be. This period of time should be long enough to allow for human response time (including `think time') between the creation of the conceptual row and the setting of the status to `active'. In the absence of such information in the DESCRIPTION clause, it is suggested that this period be approximately 5 minutes in length. This removal action applies not only to newly-created rows, but also to previously active rows which are set to, and left in, the notInService state for a prolonged period exceeding that which is considered normal for such a conceptual row. Conceptual Row Suspension When a conceptual row is `active', the management station may issue a management protocol set operation which sets the instance of the status column to `notInService'. If the agent is unwilling to do so, the set operation fails with an error of `wrongValue' or `inconsistentValue'. Otherwise, the conceptual row is taken out of service, and a `noError' response is returned. It is the responsibility of the DESCRIPTION clause of the status column to indicate under what circumstances the status column should be taken out of service (e.g., in order for the value of some other column of the same conceptual row to be modified). Conceptual Row Deletion For deletion of conceptual rows, a management protocol set operation is issued which sets the instance of the status column to `destroy'. This request may be made regardless of the current value of the status column (e.g., it is possible to delete conceptual rows which are either `notReady', `notInService' or `active'.) If the operation succeeds, then all instances associated with the conceptual row are immediately removed. · Integer32

The object is used for adding/deleting entries from this table.

Counter32

This object contains the number of probes passed for this Rserver. The probe is identified as pass if the Rserver returns a valid response.

Counter32

This object contains the number of probes failed for this Rserver. The probe is identified as failed if the Rserver fails to provide a valid response for a specified number of retries.

CiscoProbeHealthMonState1 = other2 = invalid3 = init4 = active5 = failed6 = disabledThe health monitor state of the probe for a server. The possible values are : 'other' : The health monitor state of the probe when none of the other values apply. 'invalid' : Server is not being monitored. Although user has tried to associate the probe to the server, but due to some internal problem it is actually not associated. 'init' : server is configured but not tested. 'active' : server is active. All expected responses received. 'failed' : probe has failed as expected responses have failed beyond acceptable limits. 'disabled' : probe disabled due to server being outofservice or no valid ip address configured to server. · Integer32

This object contains the health monitor state of the probe for this Rserver.

DateAndTimeA date-time specification. field octets contents range ----- ------ -------- ----- 1 1-2 year* 0..65536 2 3 month 1..12 3 4 day 1..31 4 5 hour 0..23 5 6 minutes 0..59 6 7 seconds 0..60 (use 60 for leap-second) 7 8 deci-seconds 0..9 8 9 direction from UTC '+' / '-' 9 10 hours from UTC* 0..13 10 11 minutes from UTC 0..59 * Notes: - the value of year is in network-byte order - daylight saving time in New Zealand is +13 For example, Tuesday May 26, 1992 at 1:30:15 PM EDT would be displayed as: 1992-5-26,13:30:15.0,-4:0 Note that if only local time is known, then timezone information (fields 8-10) is not present. SIZE (8 | 11) · OCTET STRING · hint 2d-1d-1d,1d:1d:1d.1d,1a1d:1d

This object indicates the date and time of the last probe.

DateAndTimeA date-time specification. field octets contents range ----- ------ -------- ----- 1 1-2 year* 0..65536 2 3 month 1..12 3 4 day 1..31 4 5 hour 0..23 5 6 minutes 0..59 6 7 seconds 0..60 (use 60 for leap-second) 7 8 deci-seconds 0..9 8 9 direction from UTC '+' / '-' 9 10 hours from UTC* 0..13 10 11 minutes from UTC 0..59 * Notes: - the value of year is in network-byte order - daylight saving time in New Zealand is +13 For example, Tuesday May 26, 1992 at 1:30:15 PM EDT would be displayed as: 1992-5-26,13:30:15.0,-4:0 Note that if only local time is known, then timezone information (fields 8-10) is not present. SIZE (8 | 11) · OCTET STRING · hint 2d-1d-1d,1d:1d:1d.1d,1a1d:1d

This object indicates the last date and time that the probe's state transitioned to 'active'

DateAndTimeA date-time specification. field octets contents range ----- ------ -------- ----- 1 1-2 year* 0..65536 2 3 month 1..12 3 4 day 1..31 4 5 hour 0..23 5 6 minutes 0..59 6 7 seconds 0..60 (use 60 for leap-second) 7 8 deci-seconds 0..9 8 9 direction from UTC '+' / '-' 9 10 hours from UTC* 0..13 10 11 minutes from UTC 0..59 * Notes: - the value of year is in network-byte order - daylight saving time in New Zealand is +13 For example, Tuesday May 26, 1992 at 1:30:15 PM EDT would be displayed as: 1992-5-26,13:30:15.0,-4:0 Note that if only local time is known, then timezone information (fields 8-10) is not present. SIZE (8 | 11) · OCTET STRING · hint 2d-1d-1d,1d:1d:1d.1d,1a1d:1d

This object indicates the last date and time that the probe's state transitioned to 'failed'

InetPortNumberRepresents a 16 bit port number of an Internet transport layer protocol. Port numbers are assigned by IANA. A current list of all assignments is available from <http://www.iana.org/>. The value zero is object-specific and must be defined as part of the description of any object that uses this syntax. Examples of the usage of zero might include situations where a port number is unknown, or when the value zero is used as a wildcard in a filter.Reference: STD 6 (RFC 768), STD 7 (RFC 793) and RFC 2960 (0..65535) · Unsigned32 · hint d

The port number of the real server. The value zero specifies that port number is not used in conjunction with real server IP Address.

Unsigned32 (0..65535)

This object specifies user configured weight of the real server under the serverfarm for the load-balancing algorithms. If value is not specified, then the value specified in the object cesRserverAdminWeight is used.

Unsigned32 (0..65535)

The actual operating weight of the real server used by the load-balancing algorithms. This can be adjusted dynamically by DFP/SASP. A weight of zero indicates that no new connections will be assigned to this real server. Higher weight values indicate to the load-balancing algorithms availability of this real server to accept more work.

Unsigned32

This object specfies the maximum number of connections that can be supported by the real server. If value is not specified, then the value specified in the object cesRserverMaxConns is used.

Unsigned32

This object specifies the minimum number of connections that needs to be supported by the real server. The value of this object must be less than or equal to value specified in cesServerFarmRserverMaxConns object. The value in this object is relevant only if the cesServerFarmMaxConns object is configured. If value is not specified, then the value specified in the object cesRserverMinConns is used.

CiscoRserverAdminStatus1 = inService2 = outOfService3 = inServiceStandbyThis is the textual convention for administrative status of the real server. The possible value(s) are : 'inService' : Places the real server into service state. 'outOfService' : Places the real server out of service. 'inserviceStandby' : Places the real server into standby state. · Integer32

This is used for setting the administrative status of the Real server a server farm.

SlbRealServerState1 = outOfService2 = inService3 = failed4 = readyToTest5 = testing6 = maxConnsThrottle7 = maxClientsThrottle8 = dfpThrottle9 = probeFailed10 = probeTesting11 = operWait12 = testWait13 = inbandProbeFailed14 = returnCodeFailed15 = arpFailed16 = standby17 = inactive18 = maxLoadThe server state represents the state of a real server being load-balanced by SLB. 'outOfService' : Server is not in use by SLB as a destination for client connections. This state can be written and read. 'inService' : Server is in use as a destination for SLB client connections. This state can be written and read. 'failed' : Server has failed and will not be retried for retry timer seconds. This state can only be read. 'readyToTest' : Server has failed and has an expired retry timer, test connections will begin flow to it soon. This state can only be read. 'testing' : Server has failed and been given another test connection, success of this connection is not known yet. This state can only be read. 'maxConnsThrottle' : Server has reached its maximum number of connections and is no longer being given connections. This state can only be read. 'maxClientsThrottle': Server has reached the maximum allowed clients. This state can only be read. 'dfpThrottle' : DFP has lowered the weight of this server to throttle level, so that no new connections will be assigned to it until DFP raises its weight. This state can only be read. 'probeFailed' : SLB probe to this this server has failed. No new connections will be assigned to it until a probe to this server succeeds. This state can only be read. 'probeTesting' : Server has received a test probe from SLB. This state can only be read. 'operWait' : Server is ready to go operational, but is waiting for the associated redirect virtual to be inservice. This state can only be read. 'testWait' : Server is ready to be tested. This state is applicable only when the server is used for http redirect load balancing. This state can only be read. 'inbandProbeFailed': Server has failed the inband Health Probe agent. This state can only be read. 'returnCodeFailed' : Server has been disabled because it returned an HTTP code that matched a configured value. This state can only be read. 'arpFailed' : ARP request to this server has failed. This state can only be read. 'standby' : Server is in standby state. No connections will be assigned to it, unless the primary server fails. This state can be written and read. 'inactive' : Server is disabled as it has become inactive such as in the case when the real server is not associated to any server farm.This state can only be read. 'maxLoad' : Server is disabled as it hit max-load. This state can only be read. · Integer32

This object provides the current state of the real server in a server farm.

SnmpAdminStringAn octet string containing administrative information, preferably in human-readable form. To facilitate internationalization, this information is represented using the ISO/IEC IS 10646-1 character set, encoded as an octet string using the UTF-8 transformation format described in [RFC2279]. Since additional code points are added by amendments to the 10646 standard from time to time, implementations must be prepared to encounter any code point from 0x00000000 to 0x7fffffff. Byte sequences that do not correspond to the valid UTF-8 encoding of a code point or are outside this range are prohibited. The use of control codes should be avoided. When it is necessary to represent a newline, the control code sequence CR LF should be used. The use of leading or trailing white space should be avoided. For code points not directly supported by user interface hardware or software, an alternative means of entry and display, such as hexadecimal, may be provided. For information encoded in 7-bit US-ASCII, the UTF-8 encoding is identical to the US-ASCII encoding. UTF-8 may require multiple bytes to represent a single character / code point; thus the length of this object in octets may be different from the number of characters encoded. Similarly, size constraints refer to the number of encoded octets, not the number of characters represented by an encoding. Note that when this TC is used for an object that is used or envisioned to be used as an index, then a SIZE restriction MUST be specified so that the number of sub-identifiers for any object instance does not exceed the limit of 128, as defined by [RFC3416]. Note that the size of an SnmpAdminString object is measured in octets, not characters. SIZE (0..255) · OCTET STRING · hint 255t

This object contains the descriptive text qualifying the reason for the value in cesServerFarmRserverOperStatus. Examples: ARP failure Health probe failed.

SnmpAdminStringAn octet string containing administrative information, preferably in human-readable form. To facilitate internationalization, this information is represented using the ISO/IEC IS 10646-1 character set, encoded as an octet string using the UTF-8 transformation format described in [RFC2279]. Since additional code points are added by amendments to the 10646 standard from time to time, implementations must be prepared to encounter any code point from 0x00000000 to 0x7fffffff. Byte sequences that do not correspond to the valid UTF-8 encoding of a code point or are outside this range are prohibited. The use of control codes should be avoided. When it is necessary to represent a newline, the control code sequence CR LF should be used. The use of leading or trailing white space should be avoided. For code points not directly supported by user interface hardware or software, an alternative means of entry and display, such as hexadecimal, may be provided. For information encoded in 7-bit US-ASCII, the UTF-8 encoding is identical to the US-ASCII encoding. UTF-8 may require multiple bytes to represent a single character / code point; thus the length of this object in octets may be different from the number of characters encoded. Similarly, size constraints refer to the number of encoded octets, not the number of characters represented by an encoding. Note that when this TC is used for an object that is used or envisioned to be used as an index, then a SIZE restriction MUST be specified so that the number of sub-identifiers for any object instance does not exceed the limit of 128, as defined by [RFC3416]. Note that the size of an SnmpAdminString object is measured in octets, not characters. SIZE (0..64) · OCTET STRING · hint 255t

This object specifies the backup real server. The value of this object cannot be same as the value specified in the INDEX cesRserverName. This value must correspond to an entry in cesRserverTable. The zero length value is not considered as a valid real server name.

InetPortNumberRepresents a 16 bit port number of an Internet transport layer protocol. Port numbers are assigned by IANA. A current list of all assignments is available from <http://www.iana.org/>. The value zero is object-specific and must be defined as part of the description of any object that uses this syntax. Examples of the usage of zero might include situations where a port number is unknown, or when the value zero is used as a wildcard in a filter.Reference: STD 6 (RFC 768), STD 7 (RFC 793) and RFC 2960 (0..65535) · Unsigned32 · hint d

This is the port number of the backup real server configured in 'cesServerFarmRserverBackupName'. This object can be configured only if the value specified in cesServerFarmRserverBackupName is valid. The value of this object is of signficance for the valid value of cesServerFarmRserverBackupName.

Counter64 (0..18446744073709551615)

The total number of connections loadbalanced to this real server.

Counter64 (0..18446744073709551615)

The number of failed connections after which the real server goes to Failed state. A failed connection is when a SYN timeouts or a RST is received from the real server.

Counter64 (0..18446744073709551615)

The total number of connections that were not connected to this server due to the current connection count being at the max number of allowed connections(cevServerFarmRserverMaxConns value) to this real server.

Counter64 (0..18446744073709551615)

The number of connections currently assigned to this real server. This object represents the connections that are still active.

StorageType1 = other2 = volatile3 = nonVolatile4 = permanent5 = readOnlyDescribes the memory realization of a conceptual row. A row which is volatile(2) is lost upon reboot. A row which is either nonVolatile(3), permanent(4) or readOnly(5), is backed up by stable storage. A row which is permanent(4) can be changed but not deleted. A row which is readOnly(5) cannot be changed nor deleted. If the value of an object with this syntax is either permanent(4) or readOnly(5), it cannot be written. Conversely, if the value is either other(1), volatile(2) or nonVolatile(3), it cannot be modified to be permanent(4) or readOnly(5). (All illegal modifications result in a 'wrongValue' error.) Every usage of this textual convention is required to specify the columnar objects which a permanent(4) row must at a minimum allow to be writable. · Integer32

The storage type for this conceptual row.

RowStatus1 = active2 = notInService3 = notReady4 = createAndGo5 = createAndWait6 = destroyThe RowStatus textual convention is used to manage the creation and deletion of conceptual rows, and is used as the value of the SYNTAX clause for the status column of a conceptual row (as described in Section 7.7.1 of [2].) The status column has six defined values: - `active', which indicates that the conceptual row is available for use by the managed device; - `notInService', which indicates that the conceptual row exists in the agent, but is unavailable for use by the managed device (see NOTE below); 'notInService' has no implication regarding the internal consistency of the row, availability of resources, or consistency with the current state of the managed device; - `notReady', which indicates that the conceptual row exists in the agent, but is missing information necessary in order to be available for use by the managed device (i.e., one or more required columns in the conceptual row have not been instanciated); - `createAndGo', which is supplied by a management station wishing to create a new instance of a conceptual row and to have its status automatically set to active, making it available for use by the managed device; - `createAndWait', which is supplied by a management station wishing to create a new instance of a conceptual row (but not make it available for use by the managed device); and, - `destroy', which is supplied by a management station wishing to delete all of the instances associated with an existing conceptual row. Whereas five of the six values (all except `notReady') may be specified in a management protocol set operation, only three values will be returned in response to a management protocol retrieval operation: `notReady', `notInService' or `active'. That is, when queried, an existing conceptual row has only three states: it is either available for use by the managed device (the status column has value `active'); it is not available for use by the managed device, though the agent has sufficient information to attempt to make it so (the status column has value `notInService'); or, it is not available for use by the managed device, and an attempt to make it so would fail because the agent has insufficient information (the state column has value `notReady'). NOTE WELL This textual convention may be used for a MIB table, irrespective of whether the values of that table's conceptual rows are able to be modified while it is active, or whether its conceptual rows must be taken out of service in order to be modified. That is, it is the responsibility of the DESCRIPTION clause of the status column to specify whether the status column must not be `active' in order for the value of some other column of the same conceptual row to be modified. If such a specification is made, affected columns may be changed by an SNMP set PDU if the RowStatus would not be equal to `active' either immediately before or after processing the PDU. In other words, if the PDU also contained a varbind that would change the RowStatus value, the column in question may be changed if the RowStatus was not equal to `active' as the PDU was received, or if the varbind sets the status to a value other than 'active'. Also note that whenever any elements of a row exist, the RowStatus column must also exist. To summarize the effect of having a conceptual row with a status column having a SYNTAX clause value of RowStatus, consider the following state diagram: STATE +--------------+-----------+-------------+------------- | A | B | C | D | |status col.|status column| |status column | is | is |status column ACTION |does not exist| notReady | notInService| is active --------------+--------------+-----------+-------------+------------- set status |noError ->D|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndGo |inconsistent- | | | | Value| | | --------------+--------------+-----------+-------------+------------- set status |noError see 1|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndWait |wrongValue | | | --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError column to | Value| entValue| | active | | | | | | or | | | | | | | |see 2 ->D|see 8 ->D| ->D --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError ->C column to | Value| entValue| | notInService | | | | | | or | | or | | | | | |see 3 ->C| ->C|see 6 --------------+--------------+-----------+-------------+------------- set status |noError |noError |noError |noError ->A column to | | | | or destroy | ->A| ->A| ->A|see 7 --------------+--------------+-----------+-------------+------------- set any other |see 4 |noError |noError |see 5 column to some| | | | value | | see 1| ->C| ->D --------------+--------------+-----------+-------------+------------- (1) goto B or C, depending on information available to the agent. (2) if other variable bindings included in the same PDU, provide values for all columns which are missing but required, and all columns have acceptable values, then return noError and goto D. (3) if other variable bindings included in the same PDU, provide legal values for all columns which are missing but required, then return noError and goto C. (4) at the discretion of the agent, the return value may be either: inconsistentName: because the agent does not choose to create such an instance when the corresponding RowStatus instance does not exist, or inconsistentValue: if the supplied value is inconsistent with the state of some other MIB object's value, or noError: because the agent chooses to create the instance. If noError is returned, then the instance of the status column must also be created, and the new state is B or C, depending on the information available to the agent. If inconsistentName or inconsistentValue is returned, the row remains in state A. (5) depending on the MIB definition for the column/table, either noError or inconsistentValue may be returned. (6) the return value can indicate one of the following errors: wrongValue: because the agent does not support notInService (e.g., an agent which does not support createAndWait), or inconsistentValue: because the agent is unable to take the row out of service at this time, perhaps because it is in use and cannot be de-activated. (7) the return value can indicate the following error: inconsistentValue: because the agent is unable to remove the row at this time, perhaps because it is in use and cannot be de-activated. (8) the transition to D can fail, e.g., if the values of the conceptual row are inconsistent, then the error code would be inconsistentValue. NOTE: Other processing of (this and other varbinds of) the set request may result in a response other than noError being returned, e.g., wrongValue, noCreation, etc. Conceptual Row Creation There are four potential interactions when creating a conceptual row: selecting an instance-identifier which is not in use; creating the conceptual row; initializing any objects for which the agent does not supply a default; and, making the conceptual row available for use by the managed device. Interaction 1: Selecting an Instance-Identifier The algorithm used to select an instance-identifier varies for each conceptual row. In some cases, the instance- identifier is semantically significant, e.g., the destination address of a route, and a management station selects the instance-identifier according to the semantics. In other cases, the instance-identifier is used solely to distinguish conceptual rows, and a management station without specific knowledge of the conceptual row might examine the instances present in order to determine an unused instance-identifier. (This approach may be used, but it is often highly sub-optimal; however, it is also a questionable practice for a naive management station to attempt conceptual row creation.) Alternately, the MIB module which defines the conceptual row might provide one or more objects which provide assistance in determining an unused instance-identifier. For example, if the conceptual row is indexed by an integer-value, then an object having an integer-valued SYNTAX clause might be defined for such a purpose, allowing a management station to issue a management protocol retrieval operation. In order to avoid unnecessary collisions between competing management stations, `adjacent' retrievals of this object should be different. Finally, the management station could select a pseudo-random number to use as the index. In the event that this index was already in use and an inconsistentValue was returned in response to the management protocol set operation, the management station should simply select a new pseudo-random number and retry the operation. A MIB designer should choose between the two latter algorithms based on the size of the table (and therefore the efficiency of each algorithm). For tables in which a large number of entries are expected, it is recommended that a MIB object be defined that returns an acceptable index for creation. For tables with small numbers of entries, it is recommended that the latter pseudo-random index mechanism be used. Interaction 2: Creating the Conceptual Row Once an unused instance-identifier has been selected, the management station determines if it wishes to create and activate the conceptual row in one transaction or in a negotiated set of interactions. Interaction 2a: Creating and Activating the Conceptual Row The management station must first determine the column requirements, i.e., it must determine those columns for which it must or must not provide values. Depending on the complexity of the table and the management station's knowledge of the agent's capabilities, this determination can be made locally by the management station. Alternately, the management station issues a management protocol get operation to examine all columns in the conceptual row that it wishes to create. In response, for each column, there are three possible outcomes: - a value is returned, indicating that some other management station has already created this conceptual row. We return to interaction 1. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it should supply a value for this column when the conceptual row is to be created. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. Once the column requirements have been determined, a management protocol set operation is accordingly issued. This operation also sets the new instance of the status column to `createAndGo'. When the agent processes the set operation, it verifies that it has sufficient information to make the conceptual row available for use by the managed device. The information available to the agent is provided by two sources: the management protocol set operation which creates the conceptual row, and, implementation-specific defaults supplied by the agent (note that an agent must provide implementation-specific defaults for at least those objects which it implements as read-only). If there is sufficient information available, then the conceptual row is created, a `noError' response is returned, the status column is set to `active', and no further interactions are necessary (i.e., interactions 3 and 4 are skipped). If there is insufficient information, then the conceptual row is not created, and the set operation fails with an error of `inconsistentValue'. On this error, the management station can issue a management protocol retrieval operation to determine if this was because it failed to specify a value for a required column, or, because the selected instance of the status column already existed. In the latter case, we return to interaction 1. In the former case, the management station can re-issue the set operation with the additional information, or begin interaction 2 again using `createAndWait' in order to negotiate creation of the conceptual row. NOTE WELL Regardless of the method used to determine the column requirements, it is possible that the management station might deem a column necessary when, in fact, the agent will not allow that particular columnar instance to be created or written. In this case, the management protocol set operation will fail with an error such as `noCreation' or `notWritable'. In this case, the management station decides whether it needs to be able to set a value for that particular columnar instance. If not, the management station re-issues the management protocol set operation, but without setting a value for that particular columnar instance; otherwise, the management station aborts the row creation algorithm. Interaction 2b: Negotiating the Creation of the Conceptual Row The management station issues a management protocol set operation which sets the desired instance of the status column to `createAndWait'. If the agent is unwilling to process a request of this sort, the set operation fails with an error of `wrongValue'. (As a consequence, such an agent must be prepared to accept a single management protocol set operation, i.e., interaction 2a above, containing all of the columns indicated by its column requirements.) Otherwise, the conceptual row is created, a `noError' response is returned, and the status column is immediately set to either `notInService' or `notReady', depending on whether it has sufficient information to (attempt to) make the conceptual row available for use by the managed device. If there is sufficient information available, then the status column is set to `notInService'; otherwise, if there is insufficient information, then the status column is set to `notReady'. Regardless, we proceed to interaction 3. Interaction 3: Initializing non-defaulted Objects The management station must now determine the column requirements. It issues a management protocol get operation to examine all columns in the created conceptual row. In the response, for each column, there are three possible outcomes: - a value is returned, indicating that the agent implements the object-type associated with this column and had sufficient information to provide a value. For those columns to which the agent provides read-create access (and for which the agent allows their values to be changed after their creation), a value return tells the management station that it may issue additional management protocol set operations, if it desires, in order to change the value associated with this column. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. However, the agent does not have sufficient information to provide a value, and until a value is provided, the conceptual row may not be made available for use by the managed device. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it must issue additional management protocol set operations, in order to provide a value associated with this column. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. If the value associated with the status column is `notReady', then the management station must first deal with all `noSuchInstance' columns, if any. Having done so, the value of the status column becomes `notInService', and we proceed to interaction 4. Interaction 4: Making the Conceptual Row Available Once the management station is satisfied with the values associated with the columns of the conceptual row, it issues a management protocol set operation to set the status column to `active'. If the agent has sufficient information to make the conceptual row available for use by the managed device, the management protocol set operation succeeds (a `noError' response is returned). Otherwise, the management protocol set operation fails with an error of `inconsistentValue'. NOTE WELL A conceptual row having a status column with value `notInService' or `notReady' is unavailable to the managed device. As such, it is possible for the managed device to create its own instances during the time between the management protocol set operation which sets the status column to `createAndWait' and the management protocol set operation which sets the status column to `active'. In this case, when the management protocol set operation is issued to set the status column to `active', the values held in the agent supersede those used by the managed device. If the management station is prevented from setting the status column to `active' (e.g., due to management station or network failure) the conceptual row will be left in the `notInService' or `notReady' state, consuming resources indefinitely. The agent must detect conceptual rows that have been in either state for an abnormally long period of time and remove them. It is the responsibility of the DESCRIPTION clause of the status column to indicate what an abnormally long period of time would be. This period of time should be long enough to allow for human response time (including `think time') between the creation of the conceptual row and the setting of the status to `active'. In the absence of such information in the DESCRIPTION clause, it is suggested that this period be approximately 5 minutes in length. This removal action applies not only to newly-created rows, but also to previously active rows which are set to, and left in, the notInService state for a prolonged period exceeding that which is considered normal for such a conceptual row. Conceptual Row Suspension When a conceptual row is `active', the management station may issue a management protocol set operation which sets the instance of the status column to `notInService'. If the agent is unwilling to do so, the set operation fails with an error of `wrongValue' or `inconsistentValue'. Otherwise, the conceptual row is taken out of service, and a `noError' response is returned. It is the responsibility of the DESCRIPTION clause of the status column to indicate under what circumstances the status column should be taken out of service (e.g., in order for the value of some other column of the same conceptual row to be modified). Conceptual Row Deletion For deletion of conceptual rows, a management protocol set operation is issued which sets the instance of the status column to `destroy'. This request may be made regardless of the current value of the status column (e.g., it is possible to delete conceptual rows which are either `notReady', `notInService' or `active'.) If the operation succeeds, then all instances associated with the conceptual row are immediately removed. · Integer32

This object is used for adding/deleting entries in the table.

SnmpAdminStringAn octet string containing administrative information, preferably in human-readable form. To facilitate internationalization, this information is represented using the ISO/IEC IS 10646-1 character set, encoded as an octet string using the UTF-8 transformation format described in [RFC2279]. Since additional code points are added by amendments to the 10646 standard from time to time, implementations must be prepared to encounter any code point from 0x00000000 to 0x7fffffff. Byte sequences that do not correspond to the valid UTF-8 encoding of a code point or are outside this range are prohibited. The use of control codes should be avoided. When it is necessary to represent a newline, the control code sequence CR LF should be used. The use of leading or trailing white space should be avoided. For code points not directly supported by user interface hardware or software, an alternative means of entry and display, such as hexadecimal, may be provided. For information encoded in 7-bit US-ASCII, the UTF-8 encoding is identical to the US-ASCII encoding. UTF-8 may require multiple bytes to represent a single character / code point; thus the length of this object in octets may be different from the number of characters encoded. Similarly, size constraints refer to the number of encoded octets, not the number of characters represented by an encoding. Note that when this TC is used for an object that is used or envisioned to be used as an index, then a SIZE restriction MUST be specified so that the number of sub-identifiers for any object instance does not exceed the limit of 128, as defined by [RFC3416]. Note that the size of an SnmpAdminString object is measured in octets, not characters. SIZE (0..255) · OCTET STRING · hint 255t

This object contains the descriptive text qualifying the real server.

SnmpAdminStringAn octet string containing administrative information, preferably in human-readable form. To facilitate internationalization, this information is represented using the ISO/IEC IS 10646-1 character set, encoded as an octet string using the UTF-8 transformation format described in [RFC2279]. Since additional code points are added by amendments to the 10646 standard from time to time, implementations must be prepared to encounter any code point from 0x00000000 to 0x7fffffff. Byte sequences that do not correspond to the valid UTF-8 encoding of a code point or are outside this range are prohibited. The use of control codes should be avoided. When it is necessary to represent a newline, the control code sequence CR LF should be used. The use of leading or trailing white space should be avoided. For code points not directly supported by user interface hardware or software, an alternative means of entry and display, such as hexadecimal, may be provided. For information encoded in 7-bit US-ASCII, the UTF-8 encoding is identical to the US-ASCII encoding. UTF-8 may require multiple bytes to represent a single character / code point; thus the length of this object in octets may be different from the number of characters encoded. Similarly, size constraints refer to the number of encoded octets, not the number of characters represented by an encoding. Note that when this TC is used for an object that is used or envisioned to be used as an index, then a SIZE restriction MUST be specified so that the number of sub-identifiers for any object instance does not exceed the limit of 128, as defined by [RFC3416]. Note that the size of an SnmpAdminString object is measured in octets, not characters. SIZE (0..255) · OCTET STRING · hint 255t

This object contains the buddy group of the real server.

StorageType1 = other2 = volatile3 = nonVolatile4 = permanent5 = readOnlyDescribes the memory realization of a conceptual row. A row which is volatile(2) is lost upon reboot. A row which is either nonVolatile(3), permanent(4) or readOnly(5), is backed up by stable storage. A row which is permanent(4) can be changed but not deleted. A row which is readOnly(5) cannot be changed nor deleted. If the value of an object with this syntax is either permanent(4) or readOnly(5), it cannot be written. Conversely, if the value is either other(1), volatile(2) or nonVolatile(3), it cannot be modified to be permanent(4) or readOnly(5). (All illegal modifications result in a 'wrongValue' error.) Every usage of this textual convention is required to specify the columnar objects which a permanent(4) row must at a minimum allow to be writable. · Integer32

The storage type for this conceptual row.

RowStatus1 = active2 = notInService3 = notReady4 = createAndGo5 = createAndWait6 = destroyThe RowStatus textual convention is used to manage the creation and deletion of conceptual rows, and is used as the value of the SYNTAX clause for the status column of a conceptual row (as described in Section 7.7.1 of [2].) The status column has six defined values: - `active', which indicates that the conceptual row is available for use by the managed device; - `notInService', which indicates that the conceptual row exists in the agent, but is unavailable for use by the managed device (see NOTE below); 'notInService' has no implication regarding the internal consistency of the row, availability of resources, or consistency with the current state of the managed device; - `notReady', which indicates that the conceptual row exists in the agent, but is missing information necessary in order to be available for use by the managed device (i.e., one or more required columns in the conceptual row have not been instanciated); - `createAndGo', which is supplied by a management station wishing to create a new instance of a conceptual row and to have its status automatically set to active, making it available for use by the managed device; - `createAndWait', which is supplied by a management station wishing to create a new instance of a conceptual row (but not make it available for use by the managed device); and, - `destroy', which is supplied by a management station wishing to delete all of the instances associated with an existing conceptual row. Whereas five of the six values (all except `notReady') may be specified in a management protocol set operation, only three values will be returned in response to a management protocol retrieval operation: `notReady', `notInService' or `active'. That is, when queried, an existing conceptual row has only three states: it is either available for use by the managed device (the status column has value `active'); it is not available for use by the managed device, though the agent has sufficient information to attempt to make it so (the status column has value `notInService'); or, it is not available for use by the managed device, and an attempt to make it so would fail because the agent has insufficient information (the state column has value `notReady'). NOTE WELL This textual convention may be used for a MIB table, irrespective of whether the values of that table's conceptual rows are able to be modified while it is active, or whether its conceptual rows must be taken out of service in order to be modified. That is, it is the responsibility of the DESCRIPTION clause of the status column to specify whether the status column must not be `active' in order for the value of some other column of the same conceptual row to be modified. If such a specification is made, affected columns may be changed by an SNMP set PDU if the RowStatus would not be equal to `active' either immediately before or after processing the PDU. In other words, if the PDU also contained a varbind that would change the RowStatus value, the column in question may be changed if the RowStatus was not equal to `active' as the PDU was received, or if the varbind sets the status to a value other than 'active'. Also note that whenever any elements of a row exist, the RowStatus column must also exist. To summarize the effect of having a conceptual row with a status column having a SYNTAX clause value of RowStatus, consider the following state diagram: STATE +--------------+-----------+-------------+------------- | A | B | C | D | |status col.|status column| |status column | is | is |status column ACTION |does not exist| notReady | notInService| is active --------------+--------------+-----------+-------------+------------- set status |noError ->D|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndGo |inconsistent- | | | | Value| | | --------------+--------------+-----------+-------------+------------- set status |noError see 1|inconsist- |inconsistent-|inconsistent- column to | or | entValue| Value| Value createAndWait |wrongValue | | | --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError column to | Value| entValue| | active | | | | | | or | | | | | | | |see 2 ->D|see 8 ->D| ->D --------------+--------------+-----------+-------------+------------- set status |inconsistent- |inconsist- |noError |noError ->C column to | Value| entValue| | notInService | | | | | | or | | or | | | | | |see 3 ->C| ->C|see 6 --------------+--------------+-----------+-------------+------------- set status |noError |noError |noError |noError ->A column to | | | | or destroy | ->A| ->A| ->A|see 7 --------------+--------------+-----------+-------------+------------- set any other |see 4 |noError |noError |see 5 column to some| | | | value | | see 1| ->C| ->D --------------+--------------+-----------+-------------+------------- (1) goto B or C, depending on information available to the agent. (2) if other variable bindings included in the same PDU, provide values for all columns which are missing but required, and all columns have acceptable values, then return noError and goto D. (3) if other variable bindings included in the same PDU, provide legal values for all columns which are missing but required, then return noError and goto C. (4) at the discretion of the agent, the return value may be either: inconsistentName: because the agent does not choose to create such an instance when the corresponding RowStatus instance does not exist, or inconsistentValue: if the supplied value is inconsistent with the state of some other MIB object's value, or noError: because the agent chooses to create the instance. If noError is returned, then the instance of the status column must also be created, and the new state is B or C, depending on the information available to the agent. If inconsistentName or inconsistentValue is returned, the row remains in state A. (5) depending on the MIB definition for the column/table, either noError or inconsistentValue may be returned. (6) the return value can indicate one of the following errors: wrongValue: because the agent does not support notInService (e.g., an agent which does not support createAndWait), or inconsistentValue: because the agent is unable to take the row out of service at this time, perhaps because it is in use and cannot be de-activated. (7) the return value can indicate the following error: inconsistentValue: because the agent is unable to remove the row at this time, perhaps because it is in use and cannot be de-activated. (8) the transition to D can fail, e.g., if the values of the conceptual row are inconsistent, then the error code would be inconsistentValue. NOTE: Other processing of (this and other varbinds of) the set request may result in a response other than noError being returned, e.g., wrongValue, noCreation, etc. Conceptual Row Creation There are four potential interactions when creating a conceptual row: selecting an instance-identifier which is not in use; creating the conceptual row; initializing any objects for which the agent does not supply a default; and, making the conceptual row available for use by the managed device. Interaction 1: Selecting an Instance-Identifier The algorithm used to select an instance-identifier varies for each conceptual row. In some cases, the instance- identifier is semantically significant, e.g., the destination address of a route, and a management station selects the instance-identifier according to the semantics. In other cases, the instance-identifier is used solely to distinguish conceptual rows, and a management station without specific knowledge of the conceptual row might examine the instances present in order to determine an unused instance-identifier. (This approach may be used, but it is often highly sub-optimal; however, it is also a questionable practice for a naive management station to attempt conceptual row creation.) Alternately, the MIB module which defines the conceptual row might provide one or more objects which provide assistance in determining an unused instance-identifier. For example, if the conceptual row is indexed by an integer-value, then an object having an integer-valued SYNTAX clause might be defined for such a purpose, allowing a management station to issue a management protocol retrieval operation. In order to avoid unnecessary collisions between competing management stations, `adjacent' retrievals of this object should be different. Finally, the management station could select a pseudo-random number to use as the index. In the event that this index was already in use and an inconsistentValue was returned in response to the management protocol set operation, the management station should simply select a new pseudo-random number and retry the operation. A MIB designer should choose between the two latter algorithms based on the size of the table (and therefore the efficiency of each algorithm). For tables in which a large number of entries are expected, it is recommended that a MIB object be defined that returns an acceptable index for creation. For tables with small numbers of entries, it is recommended that the latter pseudo-random index mechanism be used. Interaction 2: Creating the Conceptual Row Once an unused instance-identifier has been selected, the management station determines if it wishes to create and activate the conceptual row in one transaction or in a negotiated set of interactions. Interaction 2a: Creating and Activating the Conceptual Row The management station must first determine the column requirements, i.e., it must determine those columns for which it must or must not provide values. Depending on the complexity of the table and the management station's knowledge of the agent's capabilities, this determination can be made locally by the management station. Alternately, the management station issues a management protocol get operation to examine all columns in the conceptual row that it wishes to create. In response, for each column, there are three possible outcomes: - a value is returned, indicating that some other management station has already created this conceptual row. We return to interaction 1. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it should supply a value for this column when the conceptual row is to be created. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. Once the column requirements have been determined, a management protocol set operation is accordingly issued. This operation also sets the new instance of the status column to `createAndGo'. When the agent processes the set operation, it verifies that it has sufficient information to make the conceptual row available for use by the managed device. The information available to the agent is provided by two sources: the management protocol set operation which creates the conceptual row, and, implementation-specific defaults supplied by the agent (note that an agent must provide implementation-specific defaults for at least those objects which it implements as read-only). If there is sufficient information available, then the conceptual row is created, a `noError' response is returned, the status column is set to `active', and no further interactions are necessary (i.e., interactions 3 and 4 are skipped). If there is insufficient information, then the conceptual row is not created, and the set operation fails with an error of `inconsistentValue'. On this error, the management station can issue a management protocol retrieval operation to determine if this was because it failed to specify a value for a required column, or, because the selected instance of the status column already existed. In the latter case, we return to interaction 1. In the former case, the management station can re-issue the set operation with the additional information, or begin interaction 2 again using `createAndWait' in order to negotiate creation of the conceptual row. NOTE WELL Regardless of the method used to determine the column requirements, it is possible that the management station might deem a column necessary when, in fact, the agent will not allow that particular columnar instance to be created or written. In this case, the management protocol set operation will fail with an error such as `noCreation' or `notWritable'. In this case, the management station decides whether it needs to be able to set a value for that particular columnar instance. If not, the management station re-issues the management protocol set operation, but without setting a value for that particular columnar instance; otherwise, the management station aborts the row creation algorithm. Interaction 2b: Negotiating the Creation of the Conceptual Row The management station issues a management protocol set operation which sets the desired instance of the status column to `createAndWait'. If the agent is unwilling to process a request of this sort, the set operation fails with an error of `wrongValue'. (As a consequence, such an agent must be prepared to accept a single management protocol set operation, i.e., interaction 2a above, containing all of the columns indicated by its column requirements.) Otherwise, the conceptual row is created, a `noError' response is returned, and the status column is immediately set to either `notInService' or `notReady', depending on whether it has sufficient information to (attempt to) make the conceptual row available for use by the managed device. If there is sufficient information available, then the status column is set to `notInService'; otherwise, if there is insufficient information, then the status column is set to `notReady'. Regardless, we proceed to interaction 3. Interaction 3: Initializing non-defaulted Objects The management station must now determine the column requirements. It issues a management protocol get operation to examine all columns in the created conceptual row. In the response, for each column, there are three possible outcomes: - a value is returned, indicating that the agent implements the object-type associated with this column and had sufficient information to provide a value. For those columns to which the agent provides read-create access (and for which the agent allows their values to be changed after their creation), a value return tells the management station that it may issue additional management protocol set operations, if it desires, in order to change the value associated with this column. - the exception `noSuchInstance' is returned, indicating that the agent implements the object-type associated with this column, and that this column in at least one conceptual row would be accessible in the MIB view used by the retrieval were it to exist. However, the agent does not have sufficient information to provide a value, and until a value is provided, the conceptual row may not be made available for use by the managed device. For those columns to which the agent provides read-create access, the `noSuchInstance' exception tells the management station that it must issue additional management protocol set operations, in order to provide a value associated with this column. - the exception `noSuchObject' is returned, indicating that the agent does not implement the object-type associated with this column or that there is no conceptual row for which this column would be accessible in the MIB view used by the retrieval. As such, the management station can not issue any management protocol set operations to create an instance of this column. If the value associated with the status column is `notReady', then the management station must first deal with all `noSuchInstance' columns, if any. Having done so, the value of the status column becomes `notInService', and we proceed to interaction 4. Interaction 4: Making the Conceptual Row Available Once the management station is satisfied with the values associated with the columns of the conceptual row, it issues a management protocol set operation to set the status column to `active'. If the agent has sufficient information to make the conceptual row available for use by the managed device, the management protocol set operation succeeds (a `noError' response is returned). Otherwise, the management protocol set operation fails with an error of `inconsistentValue'. NOTE WELL A conceptual row having a status column with value `notInService' or `notReady' is unavailable to the managed device. As such, it is possible for the managed device to create its own instances during the time between the management protocol set operation which sets the status column to `createAndWait' and the management protocol set operation which sets the status column to `active'. In this case, when the management protocol set operation is issued to set the status column to `active', the values held in the agent supersede those used by the managed device. If the management station is prevented from setting the status column to `active' (e.g., due to management station or network failure) the conceptual row will be left in the `notInService' or `notReady' state, consuming resources indefinitely. The agent must detect conceptual rows that have been in either state for an abnormally long period of time and remove them. It is the responsibility of the DESCRIPTION clause of the status column to indicate what an abnormally long period of time would be. This period of time should be long enough to allow for human response time (including `think time') between the creation of the conceptual row and the setting of the status to `active'. In the absence of such information in the DESCRIPTION clause, it is suggested that this period be approximately 5 minutes in length. This removal action applies not only to newly-created rows, but also to previously active rows which are set to, and left in, the notInService state for a prolonged period exceeding that which is considered normal for such a conceptual row. Conceptual Row Suspension When a conceptual row is `active', the management station may issue a management protocol set operation which sets the instance of the status column to `notInService'. If the agent is unwilling to do so, the set operation fails with an error of `wrongValue' or `inconsistentValue'. Otherwise, the conceptual row is taken out of service, and a `noError' response is returned. It is the responsibility of the DESCRIPTION clause of the status column to indicate under what circumstances the status column should be taken out of service (e.g., in order for the value of some other column of the same conceptual row to be modified). Conceptual Row Deletion For deletion of conceptual rows, a management protocol set operation is issued which sets the instance of the status column to `destroy'. This request may be made regardless of the current value of the status column (e.g., it is possible to delete conceptual rows which are either `notReady', `notInService' or `active'.) If the operation succeeds, then all instances associated with the conceptual row are immediately removed. · Integer32

The object is used for adding/deleting entries from this table.