iRules Recipe 4: Static Maintenance Page
The Problem
You wish to provide a static maintenance splash page when all members of a pool serving a Virtual Server are currently down or disabled.
The Configuration
# cat /var/tmp/splash-...
Updated Jun 06, 2023
Version 2.0
VernonWells
Employee
Employee
VernonWellsEmployee
EmployeeLB_FAILED does not mean "all pool members are down". Rather, it means "a load-balancing decision cannot be made, or an attempt to proxy the traffic failed". Usually, the first happens when all members are down, but the second can occur for a variety of reasons. For example, if the pool members becomes overloaded and TCP connections timeout, then LB_FAILED will be raised.