Is it possible to do nat on firewall with nat on udp ports. if there are certain servers running service on udp port , will external access work if
we configure nat for udp access.
As you mentioned since TCP is stateful, the ASA can track the connection state and control the traffic in this way.
For UDP since it is stateless, the ASA uses short-timers to track the UDP connections.
If in a short period, there's a reply with the same source IP, source port, destination IP and destination port as the originated connection, the ASA will allow the connection through.