[Asterisk-Users] Cisco IOS crash with multiple SIP endpoints behind NAT

[David Croft]

Thought I'd drop a note here in case anyone else has been experiencing 
this. Cisco routers running NAT are liable to crash when doing NAT 
translation of SIP packets. Symptoms are a watchdog caused software 
abort in the "IP Input" process. The router then reloads. In my case 
this has been happening every ~24 hours with one SIP device behind the 
NAT and every ~15 minutes with three devices.

Cisco have identified this as bug ID CSCed42990 
(http://www.cisco.com/cgi-bin/Support/Bugtool/onebug.pl?bugid=CSCed42990) 
but it is not yet fixed in a released version. You can get an interim 
release from TAC if you have a service contract.

According to the bug description this only affects 12.3, but it 
definitely happened in the 12.2T train too (this is why we upgraded to 
12.3).

David