[asterisk-bugs] [Asterisk 0011756]: Asterisk stops responding to sip traffic if DNS doesn't respond during SIP registration

[noreply at bugs.digium.com]

The following issue has been RESOLVED. 
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http://bugs.digium.com/view.php?id=11756 
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Reported By:                staples1347
Assigned To:                file
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Project:                    Asterisk
Issue ID:                   11756
Category:                   Channels/chan_sip/General
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     resolved
Asterisk Version:           1.2.21.1 
SVN Branch (only for SVN checkouts, not tarball releases): N/A  
SVN Revision (number only!):  
Disclaimer on File?:        N/A 
Request Review:              
Resolution:                 suspended
Fixed in Version:           
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Date Submitted:             01-13-2008 00:33 CST
Last Modified:              01-14-2008 08:10 CST
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Summary:                    Asterisk stops responding to sip traffic if DNS
doesn't respond during SIP registration
Description: 
If the internet gateway goes down or the DNS server stops responding, then
during SIP registration to a VoIP provider, Asterisk will stop responding
to all SIP packets even if they are from other SIP devices such as internal
phones.

To test this either shutdown the internet gateway machine, or block DNS
request packets from the Asterisk machine and wait for the next SIP
registration.  Another way to test is set resolv.conf on the Asterisk
machine to use an invalid IP address for the DNS server, and then restart
Asterisk.

Blocking outgoing DNS directly on the Asterisk machine with iptables or
responding to the DNS request with icmp-host-unreachable 'causes a timeout
to the VoIP provider but doesn't stop other SIP traffic.
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---------------------------------------------------------------------- 
 file - 01-14-08 08:10  
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This is an issue that is already well known. The DNS resolver that we use
is blocking, which means if the DNS server is down or slow it will take
some time for it to return and thus block other things. There is nothing we
can do in 1.4 to fix this, but hopefully we'll figure something out for
1.6. 

Issue History 
Date Modified   Username       Field                    Change               
====================================================================== 
01-14-08 08:10  file           Status                   feedback => resolved
01-14-08 08:10  file           Resolution               open => suspended   
01-14-08 08:10  file           Assigned To               => file            
01-14-08 08:10  file           Note Added: 0076883                          
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