[asterisk-bugs] [Asterisk 0016755]: E1 PRI channel 'glare', where asterisk hangups up the inbound call from network.

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=16755 
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Reported By:                alecdavis
Assigned To:                
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Project:                    Asterisk
Issue ID:                   16755
Category:                   Channels/chan_dahdi
Reproducibility:            random
Severity:                   minor
Priority:                   normal
Status:                     acknowledged
Asterisk Version:           SVN 
JIRA:                       SWP-842 
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): 1.6.1 
SVN Revision (number only!): 243988 
Request Review:              
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Date Submitted:             2010-02-02 13:24 CST
Last Modified:              2010-02-08 11:59 CST
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Summary:                    E1 PRI channel 'glare', where asterisk hangups up
the inbound call from network.
Description: 
randomly we are experiencing an ISDN 'glare'.

Captures caught so far have been our IVR dialing back out to the PSTN, at
exactly the same time an incoming network call arrives.

The issue is, asterisk hangs up on the inbound call from the network, that
has the channel set to exclusive, where the outbound call has only
requested a preferred channel, which later is assigned to another channel
in the SETUP ACKNOLEDGE.

Looks like we have outbound precedence in a 'glare' situation, when really
the inbound call is probably more important.
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 (0117848) alecdavis (manager) - 2010-02-08 11:59
 https://issues.asterisk.org/view.php?id=16755#c117848 
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Now have a repeatable situation. See overlap-retry.txt

An overlap call comes in, 3 seconds later asterisk starts to make the
call, but the switch has seen anything back, other than the SETUP ACK.

After adding a proceeding to the first line of the macro that gets
executed, I cannot get it to fail.

[macro-callmobile]
exten => s,1,Proceeding()
exten => s,n,NoOp(****** Call Mobile called=${ARG1}
context=${MACRO_CONTEXT} ******)

Q.931 spec 5.2.4, 'overlap receiving' section mentions that Proceeding, or
Alerting etc should be sent after T302 times out, if asterisk deems that
it's received enough information to make the call. 

Issue History 
Date Modified    Username       Field                    Change               
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2010-02-08 11:59 alecdavis      Note Added: 0117848                          
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