This MIB contains information about the capacity and utilization of hardware resources on Arista devices.
Arista ships and supports devices which perform packet forwarding decisions in hardware. To make these forwarding decisions (L2 bridging, input and output access list, L3 forwarding based on IP destination etc.), the devices use information programmed in various hardware resources. Examples of such hardware resources are the hash table used for MAC address lookup, TCAM for destination IP lookup etc.
Each of Arista's devices have different hardware resource capacity or size limits. It is extremely useful for a Network Management system to be able to query and monitor the utilization of these hardware resources. Due to unxpected network event or configuration change, it is possible that a specific hardware resource is over utilized and there is no room to program additional entries. For example, a routing mis-configuration can result in overflowing the L3 forwarding TCAM. This may be detrimental to the network operation. So it's extremely useful to monitor the utilization of the various hardware resources of a specific device.
On some devices, due to hardware design considerations, several features may have to share a single hardware resource. If one feature ends up using more of the same resource, it can affect the functionality of another feature. This is another reason to have visibility into the hardware resource usage.
The hardware element that makes the forwarding decision is frequently referred to as the 'Forwarding ASIC' or 'Forwarding Chip'. In this MIB document we refer to this hardware element as 'Forwarding Element'. Even though a device can have multiple forwarding elements, the information programmed in each of the forwarding element is typically the same. But there are some cases, where this is not the case. In such instances, the utilization of relevant hardware resource(s) may not be the same across all the forwarding elements.
This MIB module provides the hardware capacity and utilization information for various resources in a generic manner, that's applicable to all Arista devices.
This table contains information about various hardware resources and their utilization.
aristaHardwareUtilizationResource
1.3.6.1.4.1.30065.3.22.1.1.1.1
DisplayStringRepresents textual information taken from the NVT ASCII
character set, as defined in pages 4, 10-11 of RFC 854.
To summarize RFC 854, the NVT ASCII repertoire specifies:
- the use of character codes 0-127 (decimal)
- the graphics characters (32-126) are interpreted as US ASCII
- NUL, LF, CR, BEL, BS, HT, VT and FF have the special meanings specified in RFC 854
- the other 25 codes have no standard interpretation
- the sequence 'CR LF' means newline
- the sequence 'CR NUL' means carriage-return
- an 'LF' not preceded by a 'CR' means moving to the same column on the next line.
- the sequence 'CR x' for any x other than LF or NUL is illegal. (Note that this also means that a string may end with either 'CR LF' or 'CR NUL', but not with CR.)
Any object defined using this syntax may not exceed 255 characters in length. SIZE (0..35) · OCTET STRING · hint 255a
The name that identifies the specific hardware resource.
aristaHardwareUtilizationFeature
1.3.6.1.4.1.30065.3.22.1.1.1.2
DisplayStringRepresents textual information taken from the NVT ASCII
character set, as defined in pages 4, 10-11 of RFC 854.
To summarize RFC 854, the NVT ASCII repertoire specifies:
- the use of character codes 0-127 (decimal)
- the graphics characters (32-126) are interpreted as US ASCII
- NUL, LF, CR, BEL, BS, HT, VT and FF have the special meanings specified in RFC 854
- the other 25 codes have no standard interpretation
- the sequence 'CR LF' means newline
- the sequence 'CR NUL' means carriage-return
- an 'LF' not preceded by a 'CR' means moving to the same column on the next line.
- the sequence 'CR x' for any x other than LF or NUL is illegal. (Note that this also means that a string may end with either 'CR LF' or 'CR NUL', but not with CR.)
Any object defined using this syntax may not exceed 255 characters in length. SIZE (0..35) · OCTET STRING · hint 255a
The name that identifies the specific feature which is using the hardware resource in question. As noted in the description of this MIB module, multiple features can share a specific hardware resource.
aristaHardwareUtilizationForwardingElement
1.3.6.1.4.1.30065.3.22.1.1.1.3
DisplayStringRepresents textual information taken from the NVT ASCII
character set, as defined in pages 4, 10-11 of RFC 854.
To summarize RFC 854, the NVT ASCII repertoire specifies:
- the use of character codes 0-127 (decimal)
- the graphics characters (32-126) are interpreted as US ASCII
- NUL, LF, CR, BEL, BS, HT, VT and FF have the special meanings specified in RFC 854
- the other 25 codes have no standard interpretation
- the sequence 'CR LF' means newline
- the sequence 'CR NUL' means carriage-return
- an 'LF' not preceded by a 'CR' means moving to the same column on the next line.
- the sequence 'CR x' for any x other than LF or NUL is illegal. (Note that this also means that a string may end with either 'CR LF' or 'CR NUL', but not with CR.)
Any object defined using this syntax may not exceed 255 characters in length. SIZE (0..35) · OCTET STRING · hint 255a
The name that identifies the specific forwarding element on the device that this hardware resource belongs to. As noted in the description of this MIB module, for some features information is programmed differently across various forwarding elements. In such cases, this MIB object represents the forwarding element that corresponds to this entry's hardware resource utilization. Otherwise this MIB object will just be an empty string.
aristaHardwareUtilizationInUseEntries
1.3.6.1.4.1.30065.3.22.1.1.1.4
Counter32
This MIB object represents the number of entries in the specific hardware resource that is currently consumed by a feature.
aristaHardwareUtilizationFreeEntries
1.3.6.1.4.1.30065.3.22.1.1.1.5
Counter32
This MIB object represents the number of free entries in the specific hardware resource.
aristaHardwareUtilizationCommittedEntries
1.3.6.1.4.1.30065.3.22.1.1.1.6
Counter32
This MIB object represents the number of entries of a hardware resource that have been dedicated ('reserved') for a particular feature. When features 'request' for a specific hardware resource, entries are 'reserved' for the feature. It is possible that the actual number of entries used is less than what has been reserved for the feature.
aristaHardwareUtilizationMaxEntries
1.3.6.1.4.1.30065.3.22.1.1.1.7
Counter32
This MIB object represents the maximum number of 'logical' entries that can be allocated for the given hardware resource by the specific feature (assuming it is not being shared with any other feature).
Even though the raw number of maximum entries is fixed for a given hardware resource, the logical entries available to a specific feature may vary.
An example: Consider a device where the width ('number of bits') of a single TCAM entry is 128. It is possible to store an IPv4 access control list (matching both source and destination addresses) using a single entry of this TCAM. But given that IPv6 addresses are 128 bits long, 2 TCAM entries will be required to store an equivalent IPv6 access control list.
In this example above, the 'maximum number of entries' available for the IPv4 feature is twice the number for the IPv6 feature.
aristaHardwareUtilizationHighWatermark
1.3.6.1.4.1.30065.3.22.1.1.1.8
Counter32
This MIB object represents the maximum number of entries that the specific feature has used up at any point in time. This allows the Network Management system to monitor the hardware resource utilization pattern for a given feature allowing the operator to potentially take some action.
aristaHardwareUtilizationHighWatermarkTime
1.3.6.1.4.1.30065.3.22.1.1.1.9
TimeStampThe value of the sysUpTime object at which a specific occurrence happened. The specific occurrence must be
defined in the description of any object defined using this type.
If sysUpTime is reset to zero as a result of a re- initialization of the network management (sub)system, then the values of all TimeStamp objects are also reset. However, after approximately 497 days without a re- initialization, the sysUpTime object will reach 2^^32-1 and then increment around to zero; in this case, existing values of TimeStamp objects do not change. This can lead to ambiguities in the value of TimeStamp objects. · TimeTicks
This MIB object represents the last time when a specific feature hit the high watermark (number of entries of the given hardware resource).
Trap details
aristaHardwareUtilizationAlert
1.3.6.1.4.1.30065.3.22.0.1
This notification is generated when the hardware utilization crosses the specified threshold.
aristaHardwareUtilizationInUseEntries
1.3.6.1.4.1.30065.3.22.1.1.1.4
Counter32
This MIB object represents the number of entries in the specific hardware resource that is currently consumed by a feature.
aristaHardwareUtilizationHighWatermark
1.3.6.1.4.1.30065.3.22.1.1.1.8
Counter32
This MIB object represents the maximum number of entries that the specific feature has used up at any point in time. This allows the Network Management system to monitor the hardware resource utilization pattern for a given feature allowing the operator to potentially take some action.
aristaHardwareUtilizationHighWatermarkTime
1.3.6.1.4.1.30065.3.22.1.1.1.9
TimeStampThe value of the sysUpTime object at which a specific occurrence happened. The specific occurrence must be
defined in the description of any object defined using this type.
If sysUpTime is reset to zero as a result of a re- initialization of the network management (sub)system, then the values of all TimeStamp objects are also reset. However, after approximately 497 days without a re- initialization, the sysUpTime object will reach 2^^32-1 and then increment around to zero; in this case, existing values of TimeStamp objects do not change. This can lead to ambiguities in the value of TimeStamp objects. · TimeTicks
This MIB object represents the last time when a specific feature hit the high watermark (number of entries of the given hardware resource).