iCall, SSH and run a command.

If you have a script on the F5 which can remote ssh non-interactively on to your server and execute whatever you need executed there, then 1 way to do this is via custom alert under /config/user_alert.conf.

You can setup an "exec" script which runs if a log message matches a defined string pattern. You will have to set this string pattern for the exact pool name and member values for which you want to execute the script for.

I would not recommend this approach if you find a better way. Log strings do change from version to version and also this creates a new process on your LTM if the log message matches the string pattern, which could be a potential hazard if the server flaps around.