Reference Guide

Simple Network Management Protocol (SNMP) | 867
In Figure 43-22, R1 has one dynamic MAC address, learned off of port GigabitEthernet 1/21, which a
member of the default VLAN, VLAN 1. The SNMP walk returns the values for dot1dTpFdbAddress,
dot1dTpFdbPort, and dot1dTpFdbStatus.
Each object is comprised an OID concatenated with an instance number. In the case of these objects, the
instance number is the decimal equivalent of the MAC address; derive the instance number by converting
each hex pair to its decimal equivalent. For example, the decimal equivalent of E8 is 232, and so the
instance number for MAC address 00:01:e8:06:95:ac is .0.1.232.6.149.172.
The value of dot1dTpFdbPort is the port number of the port off which the system learns the MAC address.
In this case, of GigabitEthernet 1/21, the manager returns the integer 118. The maximum line card port
density on the E-Series is 96 ports, and line card numbering begins with 0; GigabitEthernet 1/21 is the 21st
port on Line Card 1, and 96 + 21 yields 118.
Figure 43-22. Fetching Dynamic MAC Addresses on the Default VLAN
In Figure 43-23, GigabitEthernet 1/21 is moved to VLAN 1000, a non-default VLAN. Use the objects
dot1qTpFdbTable to fetch the MAC addresses learned on non-default VLANs. The instance number is the
VLAN number concatenated with the decimal conversion of the MAC address.
Figure 43-23. Fetching Dynamic MAC Addresses on Non-default VLANs
Use dot3aCurAggFdbTable to fetch the learned MAC address of a port-channel. The instance number is
the decimal conversion of the MAC address concatenated with the port-channel number.
------------------------MAC Addresses on Dell Force10 System-------------------------------
R1_E600#show mac-address-table
VlanId Mac Address Type Interface State
1 00:01:e8:06:95:ac Dynamic Gi 1/21 Active
------------------------------Query from Management Station--------------------------------
>snmpwalk -v 2c -c techpubs 10.11.131.162 .1.3.6.1.2.1.17.4.3.1
SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.232.6.149.172 = Hex-STRING: 00 01 E8 06 95 AC
SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.232.6.149.172 = INTEGER: 118
------------------------MAC Addresses on Dell Force10 System-------------------------------
R1_E600#show mac-address-table
VlanId Mac Address Type Interface State
1000 00:01:e8:06:95:ac Dynamic Gi 1/21 Active
------------------------------Query from Management Station--------------------------------
>snmpwalk -v 2c -c techpubs 10.11.131.162 .1.3.6.1.2.1.17.7.1.2.2.1
SNMPv2-SMI::mib-2.17.7.1.2.2.1.2.1000.0.1.232.6.149.172 = INTEGER: 118