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Macaron's avatar
Macaron
Icon for Nimbostratus rankNimbostratus
Mar 09, 2017

Self and Floating IP mac-address conflict

Hi, I am trying to troubleshoot one of the server behind F5 VIP. I disabled the 2 servers out of 3, to isolate the issue. The LTM is in active/standby configuration. There is self and floating ...
application delivery
LTM
Kai_Wilke's avatar
Kai_Wilke
Icon for MVP rankMVP
Mar 09, 2017

Hi Frank,

 

unless you've configured a "Masquarade MAC" on your Traffic-Group, the Self-IP and the Floating-IP will use identical MAC addresses. During a failover event, the MAC of the Floating-IP will change to the MAC address of the the Self-IP of your standby unit via gARP.

 

K13502: Configuring MAC masquerade (11.x - 12.x)

 

https://support.f5.com/csp/article/K13502

 

K14513: MAC address assignment for interfaces, trunks, and VLANs (11.x - 12.x)

 

https://support.f5.com/csp/article/K14513

 

In a cluster environment the Self-IP will be used for e.g. Monitoring traffic and the Floating-IP or other virtual addresses will be used to access your configuration objects (e.g. L3 Forwardings, L4-7 Virtual Servers, SNAT IPs / Pools, etc.)

 

So nothing unusual at this time...

 

Cheers, Kai