[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:              2009-01-11 10:58 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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 (0097449) jrast (reporter) - 2009-01-11 10:58
 http://bugs.digium.com/view.php?id=12312#c97449 
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Well, you are seeing the same IP address change as I had, so that is
demonstrating that Asterisk is switching SRVs.

When I reported this now, getting on for 10 months ago, I did also open a
ticket with Callcentric.  Their response at the time was that it was wrong
for Asterisk to switch SRVs which is why I went on to patch Asterisk. 
Since I solved the problem that way quite easily, I closed the Callcentric
ticket.

It is quite possible that, in the intervening months, Callcentric has made
changes at their end so that a re-register to the other IP now also works. 
I have not heard if that's the case, though.  It certainly looks that way. 
The re-register to the other IP address that you are seeing is where it
would have failed before.

Thanks very much for taking the trouble to test it out, by the way. 

Issue History 
Date Modified    Username       Field                    Change               
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2009-01-11 10:58 jrast          Note Added: 0097449                          
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