ARP Table via SNMP

  • Hi there,

    I read some posts about getting the arp table of the pfsense via SNMP. I am not able to get it?!
    I have enable all snmp modules; SNMP ist working:

    root@daffy:~# snmpwalk -c public -v2c  |head
    SNMPv2-MIB::sysDescr.0 = STRING: "ipdrouter.ipdynamics.local 1345880010 FreeBSD 8.1-RELEASE-p6"
    SNMPv2-MIB::sysObjectID.0 = OID: BEGEMOT-MIB::begemot.
    EXPRESSION-MIB::sysUpTimeInstance = Timeticks: (1303876) 3:37:18.76

    But no arp table:

    root@daffy:~# snmpwalk -c public -v2c  ipNetToMediaPhysAddress
    RFC1213-MIB::ipNetToMediaPhysAddress = No Such Instance currently exists at this OID
    root@daffy:~# snmpwalk -c public -v2c  ipNetToPhysicalPhysAddress
    IP-MIB::ipNetToPhysicalPhysAddress = No Such Object available on this agent at this OID
    root@daffy:~# snmpwalk -c public -v2c  ipNetToPhysicalTable
    IP-MIB::ipNetToPhysicalTable = No Such Object available on this agent at this OID

    Any suggestions?


  • Same here, apparently it was working around 1.2:

    Would be great if it came back  :)

    If I may suggest an improvement with regards to IPv6, ipNetToPhysicalPhysAddress ( table might be a nice new home for it.

    What can be observed on other networking devices (e.g. switches), that the old ipNetToMediaPhysAddress ( is kept and ipv6NetToMediaPhysAddress ( is added for ND entries…

  • I had given up on getting ARP tables from pfSense too, I didn't know it was not working and thought it was me. Would definitely like to see it working.

  • Since the SNMP data was requested by an external webserver, it is also possible to get some webpage info through this php webserver.

    Created to following script on pfSense /usr/local/www/arp.php

    $dhcpFile = shell_exec('arp -na');
    echo  $dhcpFile . "\n" ;

    E.g. https://pfsenseAddress/arp.php o wget https://pfsenseAddress/arp.php -O arp_table

  • Just tested 2.2.3-RELEASE and it's back again, yieih!!!