How to Unblock Port in HP UX => later...
how to see the list of active port?
The best is to keep updated on all your servers the /etc/services file, like that you know which port you can use (and so update services file...)
block/unblock -> That should be done by the program using that specified port
Now in case of trouble you can always do an attempt to:
ndd -set /dev/tcp tcp_discon_by_addr <the socket giving the IP address in HEX...>
but for this you need to know the culprits IP...
You should install lsof if not already on your box...