[asterisk-bugs] Asterisk 13.1.0 - retrans_pkt: Retransmission timeout reached

[Ludovic Boué]

Hello all,

Recently, we upgrade to version Asterisk 13.1.0 with chan_sip stack. With 20 calls there was no problem. But now this server handles 150 concurrent calls and I get the following error : Retransmission timeout reached on transmission

2015-02-06 00:34:08.410		Warn	local0	asterisk[28435]: WARNING[28461]: chan_sip.c:4047 in retrans_pkt: Retransmission timeout reached on transmission 05072-OA-01425d07-678a8d304 at telec ...
2015-02-06 00:34:08.400		Warn	local0	asterisk[28435]: WARNING[28461]: chan_sip.c:4076 in retrans_pkt: Hanging up call 29868-NY-01425d00-3cdf68ba3 at domain.com - no reply to our critic ...
2015-02-06 00:34:08.380		Warn	local0	asterisk[28435]: WARNING[28461]: chan_sip.c:4047 in retrans_pkt: Retransmission timeout reached on transmission 29868-NY-01425d00-3cdf68ba3 at telec ...
2015-02-06 00:33:55.586		Warn	local0	asterisk[28435]: WARNING[28461]: chan_sip.c:4076 in retrans_pkt: Hanging up call 29634-DL-01425cda-6a801a7d6 at domain.com - no reply to our critic ...
2015-02-06 00:33:55.585		Warn	local0	asterisk[28435]: WARNING[28461]: chan_sip.c:4047 in retrans_pkt: Retransmission timeout reached on transmission 29634-DL-01425cda-6a801a7d6 at telec ...

When this message appears the server begins to reject calls. They are all gradually declined. 
Have you ever encountered the same issue? We are unable to reproduce the problem.

I specified that we don't use SIP SBC or NAT in this scenario.

Regards,
Ludovic BOUÉ