Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

When you need to poll the ARP table of a device, conventional wisdom is to use ipNetToMediaPhysAddress or atPhysAddress; however, both of these OIDs are deprecated according to Cisco's documentation.

These OIDs work just fine; however, I'm building a new tool so it makes sense to use the most current OID, if possible.

Is there a non-deprecated SNMP OID to query for the ARP table in a device? Google hasn't turned this answer up for me, so far...


Mircea's answer works well on newer IOS...

[mpenning@something]$ snmpbulkwalk -v 2c -c public -Osq 192.0.2.1 ipNetToPhysicalPhysAddress
ipNetToPhysicalPhysAddress.2.ipv4."192.0.2.1" a4:4c:11:90:56:80
ipNetToPhysicalPhysAddress.2.ipv4."192.0.2.2" a4:4c:11:96:68:0
ipNetToPhysicalPhysAddress.2.ipv4."192.0.2.101" 0:90:b:43:80:74
[mpenning@something]$ snmpbulkwalk -v 2c -c public -Oqv 192.0.2.1 sysDescr
Cisco IOS Software, C3900 Software (C3900-UNIVERSALK9-M), Version 15.2(2)T1, RELEASE SOFTWARE (fc1)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2012 by Cisco Systems, Inc.
Compiled Wed 29-Feb-12 23:44 by prod_rel_team
[mpenning@something]$

Older IOS requires use of ipNetToMediaPhysAddress

share|improve this question

1 Answer 1

up vote 5 down vote accepted

You should use ipNetToPhysicalTable as defined by RFC 4293. So ipNetToMediaPhysAddress becomes ipNetToPhysicalPhysAddress

ipNetToMediaTable OBJECT-TYPE SYNTAX SEQUENCE OF IpNetToMediaEntry MAX-ACCESS not-accessible STATUS deprecated DESCRIPTION "The IPv4 Address Translation table used for mapping from IPv4 addresses to physical addresses.

        This table has been deprecated, as a new IP version-neutral
        table has been added.  It is loosely replaced by the
        ipNetToPhysicalTable."
::= { ip 22 }
share|improve this answer
    
This returns values for our stuff running IOS 15.2T, sadly that's 3 out of about 300 devices... unfortunately ipNetToPhysicalPhysAddress doesn't seem to be supported in 12.2 (what almost everything else runs). Nevertheless, you've correctly answered my question, thank you! –  Mike Pennington Oct 22 '12 at 19:24
    
You should try to use the new one and fall back on the old one if the new one is not available. –  Mircea Vutcovici Oct 22 '12 at 19:54

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.