Chapter 3 MIB Specifications
ENTITY-MIB
The following are the five conformance groups contained in the Entity-MIB:
•entityPhysical group—Describes the physical entities managed by a single agent.
•entityLogical group—Describes the logical entities managed by a single agent.
•entityMapping group—Describes the associations between the physical entities, logical entities, interfaces, and non-interface ports managed by a single agent.
•entityGeneral group—Describes general system attributes shared by potentially all types of entities managed by a single agent.
•entityNotifications group—Contains status indication notifications.
The following two groups are added from RFC 2737:
•entityPhysical2 group—This group augments the entityPhysical group.
•entityLogical2 group—Describes the logical entities managed by a single agent, and replaces entityLogical group.
The MIB table entPhysicalTable identifies the physical system components in the router. The entPhysicalTable contains 1 row for the Cisco 7304 chassis and 1 row for each entity in the chassis. A physical entity can contain other entities. The physical hierarchy of system components is determined at runtime, based on the actual router configuration.
MIB Constraints
Table 3-21lists the constraints that the router places on objects in the ENTITY-MIB. For detailed definitions of MIB objects, see the MIB.
Table 3-21 ENTITY-MIB Constraints for OSM Modules
MIB Object | Notes |
entPhysicalTable | |
• | entPhysicalAlias | Zero length string. |
• | entPhysicalAssetID | Zero length string. |
| |
entLogicalTable | |
• | entLogicalContextName | Not supported. |
| |
entLPMappingTable | Not supported. |
| | |
The following MIB entities are dependent on each user’s configuration:
•entPhysicalIndex—Uniquely identifies each entity in the router. The index is also used to access information about the entity in other MIB tables.
•entPhysicalContainedIn—Indicates the entPhysicalIndex of a component’s parent entity. The value of entPhysicalIndex for the physical entity which 'contains' this physical entity. A value of zero indicates this physical entity is not contained in any other physical entity.
•entPhysicalParentRelPos—An integer that shows the relative position of same-type entities that have the same entPhysicalContainedIn value (for example, slots and line card ports).
The entPhysicalTable contains a single row for the Cisco 7304 chassis and a row for each entity in the chassis. A physical entity may contain other entities (for example, a fan-tray bay may contain a fan-tray module, which may contain one or more fans). The physical hierarchy of system components is determined at runtime, based on the actual configuration.
Cisco 7304 Router MIB Specifications Guide
