Hi Valentine,
If you only want to use the sorry server(s) when the virtual server's default pool has no members, you can use an iRule like the one below. The VS pool will be checked on each HTTP request instead of per connection like you see with priority group activation. Update sorry_pool to the name of a second pool you create containing the sorry server(s).
when CLIENT_ACCEPTED {
Save the name of the VS default pool
set default_pool [LB::server pool]
}
when HTTP_REQUEST {
Check if the VS default pool has any active members
if {[active_members $default_pool]}{
pool $default_pool
} else {
pool sorry_pool
}
}
Aaron