Log client source IP when connecting to TCP Virtual by iRule

you can try below as well

when CLIENT_ACCEPTED {
        # Get time for start of TCP connection in milleseconds
        set tcp_start_time [clock clicks -milliseconds]
 
        # Log the start of a new TCP connection
        log local0. "New TCP connection from [IP::client_addr]:[TCP::client_port] to [IP::local_addr]:[TCP::local_port]"
    }
 
    when LB_SELECTED {
        log local0. "Client [IP::client_addr]:[TCP::client_port]: Selected [LB::server]"
     }
     when SERVER_CONNECTED {
         log local0. "Client [IP::client_addr]:[TCP::client_port]: Connected to [IP::server_addr]:[TCP::server_port]"
     }
 
     when CLIENT_CLOSED {
         # Log the end time of the TCP connection
         log local0. "Closed TCP connection from [IP::client_addr]:[TCP::client_port] to [IP::local_addr]:[TCP::local_port] (open for: [expr {[clock clicks -milliseconds] - $tcp_start_time}] ms)"
    }