[asterisk-bugs] [Asterisk 0012312]: [patch] DNS SRV lookups causing re-registration problems

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=12312 
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Reported By:                jrast
Assigned To:                putnopvut
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Project:                    Asterisk
Issue ID:                   12312
Category:                   Channels/chan_sip/Registration
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     ready for review
Target Version:             1.6.2
Asterisk Version:           1.4.18 
Regression:                 No 
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:             2008-03-26 17:38 CDT
Last Modified:              2009-01-09 08:24 CST
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Summary:                    [patch] DNS SRV lookups causing re-registration
problems
Description: 
SIP peer uses DNS SRV records which list multiple entries for
_sip._udp.domain.  

Asterisk is selecting one and successfully registering with it.  When
attempting to re-register, Asterisk is not selecting the same host. 
Instead it is ALWAYS selecting another host, sending seven SIP REGISTER
requests to it, then failing over to the next (correct) host, at which
point the re-register succeeds.  However, this process exceeds the
registration expiry and the registration is timing out on every
re-registration cycle.

Peer in question is callcentric.com.
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 (0097292) jrast (reporter) - 2009-01-09 08:24
 http://bugs.digium.com/view.php?id=12312#c97292 
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Please do not discard this work!  A fix for this problem is essential for
peering with Callcentric, and by extension, with any other peer with
multiple SRV hosts.

Unfortunately, to test this, I would have to build a completely new
Asterisk test platform since my existing one remains in production use.  My
schedule has not allowed me the time to do all that would be necessary for
this.  I had thought I would be able to by now, but in fact, further trips
away appear likely for the time being.

I did include a patch for a hack that does solve the problem, so very
specific info is available about this.  Surely someone more familiar with
the code than I can compare that and the new patch to verify that the new
one should also work.  Failing that, perhaps someone else can set up a
Callcentric account (they are free) and try out the new patch?

This is an essential patch for anyone wishing to use Callcentric with
Asterisk. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-01-09 08:24 jrast          Note Added: 0097292                          
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