Q:

cisco 2900xl - SNMP - Get mac address of device connected to an interface

Basically what i want to do is to find out what is the mac address of a device plugged in to an interface on the switch (FastEthernet0/1 for example)
reading through the switch documentaion i found out that i can configure snmp trap on it to make it notify of any new mac address the switch detects by using the command 
snmp-server enable traps mac-notifiction
but for some reason my switch does not support this feature. the only options i see are
CORE_SWITCH(config)#snmp-server enable traps ?
  c2900            Enable SNMP c2900 traps
  cluster          Enable Cluster traps
  config           Enable SNMP config traps
  entity           Enable SNMP entity traps
  hsrp             Enable SNMP HSRP traps
  snmp             Enable SNMP traps
  vlan-membership  Enable VLAN Membership traps
  vtp              Enable SNMP VTP traps
  <cr>

so the other way would be for me to run a cronjon on my gateway to poll the switch periodically using snmp to get new mac addresses
i have looked everywhere but cant seem to find the OID that would provide me this information.
any help i can get would me very much appreciated !
here's the output from "show version" on my switch
Cisco Internetwork Operating System Software
IOS (tm) C2900XL Software (C2900XL-C3H2S-M), Version 12.0(5.4)WC(1), MAINTENANCE INTERIM SOFTWARE
Copyright (c) 1986-2001 by cisco Systems, Inc.
Compiled Tue 10-Jul-01 11:52 by devgoyal
Image text-base: 0x00003000, data-base: 0x00333CD8

ROM: Bootstrap program is C2900XL boot loader

CORE_SWITCH uptime is 1 hour, 24 minutes
System returned to ROM by power-on
System image file is "flash:c2900XL-c3h2s-mz.120-5.4.WC.1.bin"

cisco WS-C2912-XL (PowerPC403GA) processor (revision 0x11) with 8192K/1024K bytes of memory.
Processor board ID FAB0409X1WS, with hardware revision 0x01
Last reset from power-on

Processor is running Enterprise Edition Software
Cluster command switch capable
Cluster member switch capable
12 FastEthernet/IEEE 802.3 interface(s)

32K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address: 00:01:42:D0:67:00
Motherboard assembly number: 73-3397-08
Power supply part number: 34-0834-01
Motherboard serial number: FAB040843G4
Power supply serial number: DAB05030HR8
Model revision number: A0
Motherboard revision number: C0
Model number: WS-C2912-XL-EN
System serial number: FAB0409X1WS
Configuration register is 0xF

thanks,
-ankit

A:

Radius, thanks for pointing me in the right direction. googled up a bit based on your sugestions and i think i have it now.
To anyone else who might need it, this is the procedure ....
1. get the mac address detected on a vlan (1 in this example)

snmpwalk -c public@1 -v2c 10.1.1.10 1.3.6.1.2.1.17.4.3.1.1
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.0 = Hex-STRING: 00 01 42 D0 67 00
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.1 = Hex-STRING: 00 01 42 D0 67 01
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.2 = Hex-STRING: 00 01 42 D0 67 02
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.3 = Hex-STRING: 00 01 42 D0 67 03
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.4 = Hex-STRING: 00 01 42 D0 67 04
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.5 = Hex-STRING: 00 01 42 D0 67 05
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.6 = Hex-STRING: 00 01 42 D0 67 06
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.7 = Hex-STRING: 00 01 42 D0 67 07
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.8 = Hex-STRING: 00 01 42 D0 67 08
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.9 = Hex-STRING: 00 01 42 D0 67 09
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.10 = Hex-STRING: 00 01 42 D0 67 0A
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.11 = Hex-STRING: 00 01 42 D0 67 0B
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.1.66.208.103.12 = Hex-STRING: 00 01 42 D0 67 0C
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.30.236.196.143.130 = Hex-STRING: 00 1E EC C4 8F 82
    SNMPv2-SMI::mib-2.17.4.3.1.1.0.80.191.232.146.174 = Hex-STRING: 00 50 BF E8 92 AE

    2. get the bridge port number for each vlan

    snmpwalk -c public@1 -v2c 10.1.1.10 1.3.6.1.2.1.17.4.3.1.2
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.0 = INTEGER: 31
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.1 = INTEGER: 13
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.2 = INTEGER: 14
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.3 = INTEGER: 15
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.4 = INTEGER: 16
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.5 = INTEGER: 17
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.6 = INTEGER: 18
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.7 = INTEGER: 19
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.8 = INTEGER: 20
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.9 = INTEGER: 22
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.10 = INTEGER: 23
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.11 = INTEGER: 24
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.1.66.208.103.12 = INTEGER: 25
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.30.236.196.143.130 = INTEGER: 15
    SNMPv2-SMI::mib-2.17.4.3.1.2.0.80.191.232.146.174 = INTEGER: 13
    SNMPv2-SMI::mib-2.17.4.3.1.2.255.255.255.255.255.255 = INTEGER: 0

3. get bridge port number to ifindex mapping

    snmpwalk -c public@1 -v2c 10.1.1.10 1.3.6.1.2.1.17.1.4.1.2

    SNMPv2-SMI::mib-2.17.1.4.1.2.13 = INTEGER: 2
    SNMPv2-SMI::mib-2.17.1.4.1.2.14 = INTEGER: 3
    SNMPv2-SMI::mib-2.17.1.4.1.2.15 = INTEGER: 4
    SNMPv2-SMI::mib-2.17.1.4.1.2.16 = INTEGER: 5
    SNMPv2-SMI::mib-2.17.1.4.1.2.17 = INTEGER: 6
    SNMPv2-SMI::mib-2.17.1.4.1.2.18 = INTEGER: 7
    SNMPv2-SMI::mib-2.17.1.4.1.2.19 = INTEGER: 8
    SNMPv2-SMI::mib-2.17.1.4.1.2.20 = INTEGER: 9
    SNMPv2-SMI::mib-2.17.1.4.1.2.22 = INTEGER: 10
    SNMPv2-SMI::mib-2.17.1.4.1.2.23 = INTEGER: 11
    SNMPv2-SMI::mib-2.17.1.4.1.2.24 = INTEGER: 12
    SNMPv2-SMI::mib-2.17.1.4.1.2.25 = INTEGER: 13

4. get the ifname

    snmpwalk -c public@1 -v2c 10.1.1.10 1.3.6.1.2.1.31.1.1.1.1

    IF-MIB::ifName.1 = STRING: VL1
    IF-MIB::ifName.2 = STRING: Fa0/1
    IF-MIB::ifName.3 = STRING: Fa0/2
    IF-MIB::ifName.4 = STRING: Fa0/3
    IF-MIB::ifName.5 = STRING: Fa0/4
    IF-MIB::ifName.6 = STRING: Fa0/5
    IF-MIB::ifName.7 = STRING: Fa0/6
    IF-MIB::ifName.8 = STRING: Fa0/7
    IF-MIB::ifName.9 = STRING: Fa0/8
    IF-MIB::ifName.10 = STRING: Fa0/9
    IF-MIB::ifName.11 = STRING: Fa0/10
    IF-MIB::ifName.12 = STRING: Fa0/11
    IF-MIB::ifName.13 = STRING: Fa0/12
    IF-MIB::ifName.14 = STRING: Nu0

so in this case the 2 mac addresses on vlan 1 are on interfaces Fa0/1 and Fa0/3

A:

I'm not sure if it's supported on 2900/IOS 12.0 but you can try to broswe dot1dTpFdbPort (.1.3.6.1.2.1.17.4.3.1.2)
You need to use a special community string including the vlan for which you want to get the mac address table: community@vlan_number
So if your switch is 1.2.3.4, use community snmpro and have vlan 30, try this:
snmpwalk -v2c -c snmpro@30 1.2.3.4 1.3.6.1.2.1.17.4.3.1.2

