Tzafrir Cohen wrote: > On Sat, Nov 08, 2008 at 02:33:18PM +1100, Rob Hillis wrote: > >>> Maybe it's me, but I think that "warning" should be regarding a problem >>> I can fix. Malformed network content does not neceserily fall under that >>> definition. "notice"? >>> >>> >> Absolutely it does. Warnings of malformed packets are often (as >> mentioned above) symptomatic of network problems. Fix the network >> problem, fix the warning. >> > > As you saw in this case, this is a monitoring program that checks if > somebody still listens on the UDP port. Would you teach nmap to try a > valid IAX packet on every UDP port? How can you tell in advance that the > port is IAX and not SIP? Or whatever UDP protocol? Why should the > monitoring program care? >
Depends on how thorough you want the monitoring program to be. Personally if I were monitoring a service, I'd want to know that the service was responding the way you were expecting it to rather than blindly checking whether the port was open. However, one of my previous job was to monitor a large network that was running software that I would consider to be pretty badly broken and the fact that a port was open meant nothing more than the executable was still running - it was quite common for the software behind it to have gone into an infinite loop that promptly ignored all other data. I learnt to be incredibly paranoid if I wanted to be sure that everything was working the way it was supposed to be. UDP presents it's own challenges when it comes to monitoring anyway since there's no guarantee you'll get a reply from the other end. However, in the case of a program such as nmap, I take your point. Nmap is more interested in whether a port is open than whether the software is fully functional or not. _______________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users