[asterisk-bugs] [Asterisk 0012792]: Dropped calls with: Maximum retries exceeded on transmission

[noreply at bugs.digium.com]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=12792 
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Reported By:                digmaster
Assigned To:                
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Project:                    Asterisk
Issue ID:                   12792
Category:                   Channels/chan_sip/General
Reproducibility:            sometimes
Severity:                   major
Priority:                   normal
Status:                     new
Asterisk Version:           1.4.19 
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
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Date Submitted:             06-05-2008 01:23 CDT
Last Modified:              06-05-2008 04:46 CDT
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Summary:                    Dropped calls with: Maximum retries exceeded on
transmission
Description: 
We get lots of dropped calls with the following warning in the logs:

chan_sip.c: Maximum retries exceeded on transmission
2cc62c79934cc54c at 192.168.1.102 for seqno 35083 (Critical Response).

We use asterisk 1.4.19 with trixbox, a beronet 2-port ISDN PCI card and
some Grandstream phones. This happens on 2 out of 10 calls, but when it
happens it drops the call while the two people are actively talking.

After further tests, we thought that the UDP port was timing out, but that
wasn't the case since communication seemed ok.


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 digmaster - 06-05-08 04:46  
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Grandstream -SIP> asterisk -ISDN-BRI> telco -ISDN-BRI> phone

Unfortunately, this is a production environment and we couldn't reproduce
the problem on our test environment, otherwise i would have reported the
SIP history.

In addition, the problem can't be reproduced by hand... since... it just
happens. Maybe not at random but we haven't figured a way to reproduce it
by hand.

We did enable DEBUG mode on the Grandstream phones and got several logs
with SIP messages: 481, 487, 484 and 415.

Its weird because some of them aren't supposed to appear, for exaple 415
"unsupported media type" doesn't make sense because the server and the GS
phone support all available codecs and they are properly enabled in their
configs.

I'm sorry i haven't managed to provide more details. 

Issue History 
Date Modified   Username       Field                    Change               
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06-05-08 04:46  digmaster      Note Added: 0087836                          
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