Wildcard Forwarding Virtual Server

Perhaps it is not the most elegant solution, but if you need a quick fix you could simply log out the IP addresses the first time they connect with an iRule. This will make it easily searchable in /var/log/ltm. Example:

when CLIENT_ACCEPTED
{
    if { [table lookup counter] eq ""}
    {
        table set counter 0
    }
    set client_address [IP::remote_addr]
    if { [table lookup $client_address] eq "" } {
        table set $client_address 1 60400
        log local0. "ADDRESS CONNECTED $client_address"
        table incr counter
        log local0. "TOTAL USERS [table lookup counter]"
    }
    else
    {
        log local0. "ADDRESS RECONNECTED $client_address"
    }
    
}

This example will cache all the IPs coming in and log out when they connect and reconnect. The reconnect line can be commented out for easier readability. This example is set to cache the IP addresses for 1 week. This example also stores a counter to see how many IP address were stored

Hope this helps.