Forum Discussion
NimbostratusWhich 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 traffic-group /common/traffic-group-1 {
ha-order {
/common/bigip1.local
/common/bigip2.local
}
mac 12:13:14:15:16:17
unit 1
}
############################
also if in the case is that the fail-over method is load-aware and what will be the active member if they have the same utilization.
I tried these labs but could not find any documentation of these test.
Thanks in advance
Joe_ReifelEmployee
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_ordazThx 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
annliuAltostratus
After recover from split-brain event,the one who has bigger mgmt ip will become active ,other one will be standby. such as ,192.168.1.245 & 192.168.1.246, the 246 will become active ,also 192.168.1.245& 192.168.5.245,the 192.168.5.245 one will become active.
NUT2889Cirrostratus
Hi,
Base on traffic group fail-over method. The default thing is load aware.
From the KB mention below.
The BIG-IP system implements load-aware failover by calculating a numeric, current utilization score for each device, based on numeric values that you specify for each device and traffic group relative to the other devices and traffic groups in the device group. The system then uses this current utilization score to determine which device is the best device in the group to become the next-active device when failover occurs for a traffic group.
Refer more details from https://techdocs.f5.com/kb/en-us/products/big-ip_ltm/manuals/product/bigip-device-service-clustering-admin-11-6-0/13.html