Config of Generic host with multiport.

I guess the answer depends on the definition of "multiple ports". Is it a specific set of ports, or any/all ports?

If it's any/all ports, you can simply create a VIP with a wildcard port (*), disable port translation, and send to a pool that also uses wildcard ports. A request coming in to IP:1414 will get sent to the pool on port 1414, and hopefully there will be a server there listening on port 1414 to receive this.

If it's a specific set of ports, you cannot define a single VIP this way. You can allow all ports and then limit what's accepted in an iRule (blocking everything else).

On the monitor question, you'd want to use a port-agnostic monitor, like an ICMP 'ping'.