[asterisk-users] pjsip: occasional sip_transactio Unable to register REGISTER transaction (key exists)

[Michael Maier]

Hello!

I occasionally can see warnings like these during *idle* times in
asterisk log (asterisk 13.7.2):

[2016-06-05 06:11:51] WARNING[27817] pjsip:     sip_transactio Unable to
register REGISTER transaction (key xists)
[2016-06-05 06:11:51] WARNING[27817] pjsip:     sip_transactio Unable to
register REGISTER transaction (key exists)

Nothing more. The third REGISTER package works as expected.


What's going on:
My phone regularly (each 7.5 minutes) sends REGISTER. Sometimes, those
REGISTERs are denied like seen above (mostly already the second REGISTER
works and no third REGISTER is needed).

The reRegistering of the phone normally works like this (as seen in
wireshark):

-> REGISTER				06:04:19:285
<- 401 Unauthorized			06:04:19:287
-> REGISTER				06:04:19:316
<- 200 OK				06:04:19:376


If warnings happen like the one mentioned above, the following can be
seen in wireshark:

-> REGISTER				06:11:49:359
<- 401 Unauthorized			06:11:49:362
-> REGISTER				06:11:49:392	Unable ...
-> REGISTER				06:11:49:876	Unable ...
-> REGISTER				06:11:50:868
<- 200 OK				06:11:51:634

The second, third and fourth register package look completely identical
to me according wireshark regarding SIP.

Notice the big latency between the fourth register and the following 200
OK: there are nearly 0.8 seconds in between in the problem case - but
normally, there are just 0.06 seconds between REGISTER and 200 OK!

What happened during these 0.8 seconds? Asterisk (and the complete
machine) has been completely idle at this time - there wasn't any call
or anything other to process.

I've got the complete wireshark trace of the situation described above.



Any idea?
Kind regards,
Michael