[asterisk-users] Recurring SIP problem with asterisk 11.6 & 11.7

[Jeremy Kister]

I have regularly (once a week, once per few hundred calls?) been having 
problems with Asterisk's SIP stack not responding to packets from any of 
my registered devices.  In the past, I could not tolerate the outage, so 
i would restart asterisk to make things happy.

My Asterisk server is currently in this broken state and I can leave it 
this way for a short while.  Devices are registered to it and I can 'sip 
qualify peer xxx'.  'sip show peer xxx' all show Status OK.

but whenever one of the devices tries to make a new call, Asterisk just 
doesnt respond.  'sip set debug on' shows no packets.

from the asterisk server (10.1.0.3), i can see one of my phones 
(10.1.0.111) trying to make a call:
# tcpdump -i eth0 -s 0 -t -n host 10.1.0.111
ARP, Request who-has 10.1.0.3 tell 10.1.0.111, length 46
ARP, Reply 10.1.0.3 is-at 00:0c:29:07:39:8e, length 28
IP 10.1.0.111.5060 > 10.1.0.3.5060: SIP, length: 926
IP 10.1.0.111.5060 > 10.1.0.3.5060: SIP, length: 926
IP 10.1.0.111.5060 > 10.1.0.3.5060: SIP, length: 926
IP 10.1.0.111.123 > 10.1.0.3.123: NTPv3, Client, length 48
IP 10.1.0.3.123 > 10.1.0.111.123: NTPv3, Server, length 48
IP 10.1.0.111.5060 > 10.1.0.3.5060: SIP, length: 926
IP 10.1.0.111.5060 > 10.1.0.3.5060: SIP, length: 926
IP 10.1.0.111.5060 > 10.1.0.3.5060: SIP, length: 926
IP 10.1.0.111.123 > 10.1.0.3.123: NTPv3, Client, length 48
IP 10.1.0.3.123 > 10.1.0.111.123: NTPv3, Server, length 48
ARP, Request who-has 10.1.0.111 tell 10.1.0.3, length 28
ARP, Reply 10.1.0.111 is-at 00:13:c4:01:da:4a, length 46
IP 10.1.0.111.5060 > 10.1.0.3.5060: SIP, length: 926
IP 10.1.0.111.5060 > 10.1.0.3.5060: SIP, length: 926
IP 10.1.0.111.5060 > 10.1.0.3.5060: SIP, length: 926

any ideas how we can find out what's upset ?