Getting mac-address-table through SNMP on a 1811

[obilodeau]

Hi,

For the past few days I've been trying to fetch the equivalent of the mac-address-table on a 1811 with SNMP. I want a mapping between active MACs to a port ifIndex (not a VLAN interface ifIndex).

- I've snmpwalked every MIBs on this device (including all the proprietary MIBs supported by the IOS)

- I've upgraded to latest IOS from the 12.4(24)T series and also tried latest from 12.4(15)T series

- I am aware of the community index (@ sign in read-only community to split per vlan)

- I've exhausted all my google skills

On 29xx, 35xx, we obtain that information using the BRIDGE-MIB, community indexing and the following OID:

1.3.6.1.2.1.17.4.3.1.2 (dot1dTpFdbPort)

ex:

# snmpwalk -v 2c -c public@1 192.168.1.61 1.3.6.1.2.1.17.4.3.1.2

SNMPv2-SMI::mib-2.17.4.3.1.2.0.23.89.208.164.62 = INTEGER: 24

SNMPv2-SMI::mib-2.17.4.3.1.2.0.23.101.255.67.177 = INTEGER: 12

SNMPv2-SMI::mib-2.17.4.3.1.2.0.24.25.113.78.52 = INTEGER: 11

The MAC is in OID format there and the result is the dot1dPort that you can convert using dot1dBasePortIfIndex (1.3.6.1.2.1.17.1.4.1.2).

I've tried pretty much everything and I'm pretty sure the switch doesn't support it, this post is a last resort. I know that the 1800s are routers but they still have 8 switch ports, I just can't believe that this information is not available through SNMP..

Note: I am not interested in getting the MAC address of the interfaces themselves but the devices connected to them.

Thanks for your help!

[Joe Clarke · Accepted solution]

What you want to do is not possible in your version of code.  There is an enhancement request open for getting this, but it was not implemented until 15.1T code.

[obilodeau]

Does that mean that 15.1.1-XB(ED) (latest available when looking for a 1811 IOS) would do it? I guess I want to wait until a T release..

From further reading I also had the impression that a 1841 or 1861 with a Ethernet HWIC would have the BRIDGE / Q-BRIDGE information I am looking for. Is it possible?

Thanks for your help! It is invaluable!

[Joe Clarke]

The bug says that is was implemented only for the T train.  Even if you had a switch module for a router, you would need 15.1T to get BRIDGE-MIB support.

[Liridon Qarkaxhija]

dot1d show only mac addresses on vlan 1 - 1001. What about for mac addresses coming on extended vlans? Is it possible with IOS 15.1?