Try sending a Control-C AKA "\x03". I'm not sure what other keys combos kill a process in linux. I'm not sure what exactly your "shell" is, are you telneting (or encrypted telnet) into the ILO module or starting a app at a prompt that connects to the ILO module? Start Wireshark (not sure if it works on Linux), start the session to the ILO module, unencrypted, do whatever key strokes you need to do by hand, stop capturing in wireshark, review the traffic for the key sequences. If you can't do it by hand at a telnet window, you can't do it with perl.