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sergio_ordaz's avatar
sergio_ordaz
Icon for Nimbostratus rankNimbostratus
Jan 07, 2020

Which device should be active after a failover

Hi to all,   I am studying and doing some labs, an I want to know if there is a some kb or documentation where it says which device should be active after and split-brain event. For example:   cm...
application delivery
BIG-IP
LTM
Joe_Reifel's avatar
Joe_Reifel
Icon for Employee rankEmployee
Jan 07, 2020

The best reference is probably the manual on failover. I'm not sure which version you're on but here's the one for BIG-IP version 13.1, called Managing Failover.

 

Based on your configuration example you have Preferred Device Over (ha-order) explicitly configured, and auto-failback is not enabled. I think your question is, what happens if bigip1.local and bigip2.local can't talk to each other on the failover communication channel for a while, resulting in both devices being active for a while?

 

When failover communication is restored between bigip1.local and bigip2.local, the sod daemon will negotiate which device should become active (Disconnected). In this case, with all things being equal, the sod daemon will select the device with the higher management IP to become active.

 

sergio_ordaz's avatar
sergio_ordaz
Icon for Nimbostratus rankNimbostratus
Jan 08, 2020

Thx for the answer i am running 11.5, its wierd because I Also though that was something with the managment IP, but i change the ip of the bigip2 to the higher one and still the bigip1 continuos to be elective after they both went active active I will read that documentation but i will read again