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Forum Discussion

Amitabha_118500's avatar
Amitabha_118500
Icon for Nimbostratus rankNimbostratus
Oct 15, 2014

Servers/Nodes behind F5 having on and off issue connecting to servers outside

Hello DevCentral Experts, Servers/Nodes are using F5 as default gateway. We are experiencing name resolution issue from the nodes behind F5 resolving to a server outside of F5. Sometimes it works, so...
NikhilB_149913's avatar
NikhilB_149913
Historic F5 Account
Oct 16, 2014

When executing a telnet or ping: are you doing this via the hostname or ip address? Do you see a difference when executing both?

 

  • Amitabha_118500's avatar
    Amitabha_118500
    Icon for Nimbostratus rankNimbostratus
    Oct 17, 2014
    We have found the cause of the problem. The Nodes behind F5 is using fault tolerance NIC team. Servers have 2 NICs. One will transmit and receive. The other one will transmit only. We changed the NIC teaming config to have one interface active at a time. This NIC teaming config was not a problem for ACE and is not a problem for Cisco ASA, but it's a issue for F5. Does anyone know why? How does F5 handle ARP?