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

[noreply at bugs.digium.com]

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:              03-17-2008 09:54 CDT
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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 - 03-17-08 09:54  
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santialel:

This is something you probably should call Digium technical support about.
 If you'd like a work around, you can set PRI timer t309 in zapata.conf  to
something other than 0 (6000 to 12000 ms) and that will maintain your
active calls while the data link layer is coming back up. 

Issue History 
Date Modified   Username       Field                    Change               
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03-17-08 09:54  mattf          Note Added: 0084060                          
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