We recently deployed a shit ton of Cisco 7841 phones.  We ran 95% of the ATP successfully and then got to the best part.  We get to knock down the WAN and send the phones into SRST mode.  For the first 10 minutes everything looked peachy, then all of a sudden the SIP registrations on the gateway decided to be punk ass bitches.  We were holding steady at around 200 registrations when we had close to 600 SIP endpoints.  Three of us stared at Secure CRT with the same anticipation as a 6 year old on Christmas morning.  Unfortunately we suffered the same disappointment as most kids who ask for a bike for Christmas and then received a box full of beaver droppings.  The registrations stopped and then at one point started losing registrations.  This was some bull shit.  It was late and we wanted to go drinking.  Well of course after an hour of troubleshooting this stupid shit, I made the brilliant assessment that I should probably call the “experts” at Cisco TAC.  So after 5 hours on the call with backbone support and then getting developers involved, we came to the conclusion that the firmware load we are using has issues with SRST.

SO FYI this load “sip78xx.10-1-1SR2-1” can lick my sack.

We added this beauty “sip78xx.10-1-1ES7” and guess what….those little bitches registered.  However, we didn’t want to introduce a new load cluster wide without doing a major bug scrub.  So we rolled back and decided that if the system goes into SRST mode…some of those people are just fucked.