[asterisk-bugs] [LibPRI 0012153]: librpi: Data link layer does not re-establish connection as described in section 5.8.9 of Q.931

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A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=12153 
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Reported By:                alerios
Assigned To:                mattf
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Project:                    LibPRI
Issue ID:                   12153
Category:                   General
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     assigned
Asterisk Version:           1.4.18 
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:             03-05-2008 15:21 CST
Last Modified:              03-05-2008 15:41 CST
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Summary:                    librpi: Data link layer does not re-establish
connection as described in section 5.8.9 of Q.931
Description: 
I'm having incoming call drops in different systems, all with the same
pattern:   

The call is established normally, with STETUP, CALL_PROCEDING, CONNECT,
and CONNECT_ACK, but then after a random while we get a DISCONNECT (cause
27) from the Telco, followed by our RELEASE and RELEASE_COMPLETE.

According to section 5.8.9 of ITU-T Q.931 (05/98), the DISCONNECT message
with cause 27 (destination out of order) is sent by the Telco wen its
internal T309 timer expires after trying to re-establish layer 2
connection.  Looking at the Q921 supervisory messages, it seems that no
frame errors are detected by libpri, or at least they are not shown.

This may be a telco side-issue related to their t309 timer, but I still
believe asterisk+libpri have something to do with it because when using an
ISDN tester or a legacy PBX the calls don't get dropped.
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---------------------------------------------------------------------- 
 mattf - 03-05-08 15:41  
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Although that is an interesting supposition, in your logs, I do not see any
indication of the data link layer failing during this call.  Without some
way  to prove what is going on, or at least point closer to what this bug
might actually be, I can't see anything further to do with it.

I'll leave this up for a few days if anyone else wants to try their hand
at this. 

Issue History 
Date Modified   Username       Field                    Change               
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03-05-08 15:41  mattf          Note Added: 0083488                          
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