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mbrandon32's avatar
mbrandon32
Icon for Cirrus rankCirrus
Jan 06, 2022

LTM Self IP Netmask Update

We will be making some network changes that will require us to update the netmask for our self IPs. Based on the following article - https://support.f5.com/csp/article/K14123529 - the steps to update...
application delivery
BIG-IP
LTM
CA_Valli's avatar
CA_Valli
Icon for MVP rankMVP
Jan 07, 2022

Hello mbrandon, just a heads up: the articole you quoted details operation to change HA self-ip's -- so the only way to do it would be rebuilding HA.

 

One of the devices will be put offline (to avoid split brain or active/active connections) and will not receive traffic, but before rebuilding HA both units must have been configured with the correct self IP's ; doing it one unit at a time would mean rebuild cluster twice.

 

If you're changing a self-ip of one of your traffic networks, you should be able to do so without all of that operation.

Just remove any floating IP's, update netmask on self (both nodes) and reconfigure floatings.

Adding/deleting floatings should have the unit sent GARP advertisements, but to be sure you can follow K19910045 instruction (create fake vlan+self and remove them)

 

Last thing, I'd recommend a maintenance window if the network you're changing has traffic on it. And 110% recommend maintenance window if you need to rebuild HA.