White Papers

Entity MIBS
The Entity MIB provides a mechanism for presenting hierarchies of physical entities using SNMP tables. The Entity MIB contains
the following groups, which describe the physical elements and logical elements of a managed system. The following tables are
implemented for the Aggregator.
● Physical Entity: A physical entity or physical component represents an identifiable physical resource within a managed
system. Zero or more logical entities may utilize a physical resource at any given time. Determining which physical
components are represented by an agent in the EntPhysicalTable is an implementation-specific matter. Typically, physical
resources (for example, communications ports, backplanes, sensors, daughter-cards, power supplies, and the overall
chassis), which you can manage via functions associated with one or more logical entities, are included in the MIB.
● Containment Tree: Each physical component may be modeled as contained within another physical component. A
containment-tree is the conceptual sequence of entPhysicalIndex values that uniquely specifies the exact physical location
of a physical component within the managed system. It is generated by following and recording each entPhysicalContainedIn
instance up the tree towards the root, until a value of zero indicating no further containment is found.
Example of Sample Entity MIBS outputs
Dell#show inventory optional-module
Unit Slot Expected Inserted Next Boot Status/Power(On/Off)
------------------------------------------------------------------------
1 0 SFP+ SFP+ AUTO Good/On
1 1 QSFP+ QSFP+ AUTO Good/On
* - Mismatch
Dell#
The status of the MIBS is as follows:
$ snmpwalk -c public -v 2c 10.16.150.162 .1.3.6.1.2.1.47.1.1.1.1.2
SNMPv2-SMI::mib-2.47.1.1.1.1.2.1 = ""
SNMPv2-SMI::mib-2.47.1.1.1.1.2.2 = STRING: "PowerEdge-FN-410S-IOA"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.3 = STRING: "Chassis 0 container"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.4 = STRING: "Module 0"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.5 = STRING: "Unit: 0 Port 1 10G Level"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.6 = STRING: "Unit: 0 Port 2 10G Level"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.7 = STRING: "Unit: 0 Port 3 10G Level"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.8 = STRING: "Unit: 0 Port 4 10G Level"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.9 = STRING: "Unit: 0 Port 5 10G Level"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.10 = STRING: "Unit: 0 Port 6 10G Level"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.11 = STRING: "Unit: 0 Port 7 10G Level"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.12 = STRING: "Unit: 0 Port 8 10G Level"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.13 = STRING: "Unit: 0 Port 9 10G Level"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.14 = STRING: "Unit: 0 Port 10 10G Level"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.15 = STRING: "Unit: 0 Port 11 10G Level"
SNMPv2-SMI::mib-2.47.1.1.1.1.2.16 = STRING: "Unit: 0 Port 12 10G Level"
shathishmuthu@login-maa-107 ~ $
SNMP Traps for Link Status
To enable SNMP traps for link status changes, use the snmp-server enable traps snmp linkdown linkup
command.
Standard VLAN MIB
When the Aggregator is in Standalone mode, where all the 4000 VLANs are part of all server side interfaces as well as the
single uplink LAG, it takes a long time (30 seconds or more) for external management entities to discover the entire VLAN
membership table of all the ports. Support for current status OID in the standard VLAN MIB is expected to simplify and speed
up this process. This OID provides 4000 VLAN entries with port membership bit map for each VLAN and reduces the scan for
(4000 X Number of ports) to 4000.
Simple Network Management Protocol (SNMP)
735