On Tue, 2009-12-15 at 15:18 -0600, think wrote: > Today after a few internet gateway outages I started receiving this > message SIP/2.0 482 Loop detected and basically can't make any calls > in or out. I was wondering if anyone could give me more information > about what it is that this means and what cold cause such a thing on a > system stable for months without changes.
Well, what it means depends on where the response originates. Generically, it means that something detected that the same message was routed more than once to whoever sent the response. If it is being originated by sipXproxy there will be a 'Server' header that says 'sipXecs/sipXproxy' and a Warning header. The response text will also say something like "Loop detected with 2 hops ago". The way this can happen on a system that is "without changes" is that the error has been there all along, but SIP is good at concealing errors. The system forks messages according to your routing rules, aliases, DNS entries, etc... if one of those forks is a loop, it cuts off that fork and proceeds with others - as long as one of the others produces a 'better' final status than 402, then the proxy will forward the 'better' status back toward the caller and you'll never see it. If the route to your gateway was the one producing a better result (likely), then the loop detected error would start to show. To debug this, you'll need to trace the message flow and see what's going wrong. See: http://sipx-wiki.calivia.com/index.php/Display_SIP_message_flow_using_Sipviewer#Getting_SIP_Messages_to_display when you get the trace data, take a look at it using sipviewer and/or post the trace with a description of your configuration (identify components by IP address), what you were doing, and which call in the trace you're talking about (by call-id or frame number in the trace, preferably). _______________________________________________ sipx-users mailing list [email protected] List Archive: http://list.sipfoundry.org/archive/sipx-users Unsubscribe: http://list.sipfoundry.org/mailman/listinfo/sipx-users sipXecs IP PBX -- http://www.sipfoundry.org/
