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Mathew_58740's avatar
Mathew_58740
Icon for Nimbostratus rankNimbostratus
Jul 13, 2014

what is the MAC address of a floating IP Address in f5 11.3.0 TMOS ADVERTISES TO NEXT HOP

what is the MAC address of a floating IP Address in f5 11.3.0 TMOS ADVERTISES TO NEXT HOP

 

9 Replies

  • nathe's avatar
    nathe
    Icon for Cirrocumulus rankCirrocumulus

    Should be the Mac address of the physical interface on that vlan.

     

  • aj1's avatar
    aj1
    Icon for Nimbostratus rankNimbostratus

    ^No, its not. Anyone knows the answer to this. Where in the F5 config can i find this mac? Any help appreciated. Thanks!

     

    • nathe's avatar
      nathe
      Icon for Cirrocumulus rankCirrocumulus
      Shaggy offers great advice there. I'm not using Mac masquerade and I can confirm my ARP table says the same Mac as the associated vlan
    • aj1's avatar
      aj1
      Icon for Nimbostratus rankNimbostratus
      Yeah, sorry about that. I was trying to find the mac a load balanced host is seeing in bigip_base.conf and under tmsh list /net interface, but couldn't find anything. I see it now though using tmsh show /net self. Thanks a ton shaggy.
  • ^No, its not. Anyone knows the answer to this. Where in the F5 config can i find this mac? Any help appreciated. Thanks!

     

    • nathe's avatar
      nathe
      Icon for Cirrocumulus rankCirrocumulus
      Shaggy offers great advice there. I'm not using Mac masquerade and I can confirm my ARP table says the same Mac as the associated vlan
    • aaaa_138357's avatar
      aaaa_138357
      Icon for Nimbostratus rankNimbostratus
      Yeah, sorry about that. I was trying to find the mac a load balanced host is seeing in bigip_base.conf and under tmsh list /net interface, but couldn't find anything. I see it now though using tmsh show /net self. Thanks a ton shaggy.
  • shaggy's avatar
    shaggy
    Icon for Nimbostratus rankNimbostratus

    If you have mac-masquerade configured, it will use the mac assigned to the floating self-IP's traffic group:

    tmsh list cm traffic-group traffic-group-1 mac

    Otherwise, it should take on the mac-address associated with its vlan:

    tmsh show net self (name of floating-ip)

    If neither of those work for you, go to a device in the same subnet as the floating self-IP (such as the standby F5 if you have an HA pair), ping the floating IP, and look at your ARP table. F5 commands for those tasks:

    tmsh run util ping (floating-ip)

    tmsh show net arp | grep (floating-ip)

    SOL14513: MAC address assignment for interfaces, trunks, and VLANs (11.x) - https://support.f5.com/kb/en-us/solutions/public/14000/500/sol14513.html