[asterisk-bugs] [Asterisk 0013900]: [feature request] Asterisk does not respect DNS TTL in iax.conf

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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http://bugs.digium.com/view.php?id=13900 
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Reported By:                ffadaie
Assigned To:                mvanbaak
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Project:                    Asterisk
Issue ID:                   13900
Category:                   Channels/chan_iax2
Reproducibility:            always
Severity:                   feature
Priority:                   normal
Status:                     assigned
Asterisk Version:           1.4.22 
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:             2008-11-13 23:07 CST
Last Modified:              2008-12-17 15:43 CST
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Summary:                    [feature request] Asterisk does not respect DNS TTL
in iax.conf
Description: 
This is probably not specific to IAX but I just tried it for IAX so I am
not sure about the other channels.
The problem is :
when you Dial and IAX channel either by direct dialing
Dial(IAX2/@some_host_name/extension) or by referring to a section in
iax.conf Dial(IAX2/@[section]/extension) and the host names are not IP
addresses but DNS names, Asterisk does not care if the resolved address
changes.
In other words, lets say you have a dynamic DNS that translates to IP_1
and you use this in your configuration in Asterisk. If this IP changes
Asterisk would not respect it and keeps using the old IP until you reload.
It seems that Asterisk resolves the DNS and stores the IP in the memory
(as oppose to having the DNS entry and resolving it each time)
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 (0096592) mvanbaak (manager) - 2008-12-17 15:43
 http://bugs.digium.com/view.php?id=13900#c96592 
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Ok, here's the way I see we can fix this.

- The functionality as it is now remains.
- Instead of hardcoding the refreshtime in dnsmanager we are going to
alter the refresh interval of it based on the lowest TTL returned by the
lookups dnsmanager does for us.

So if you want results based on the TTL you have to use dnsmanager.

This way we fix it for all modules the same way, and the patch will be
easy to review because it will only touch 1 maybe two files.

Discussion on IRC made seanbright and jsmith agree with this idea.
If you agree, or dont agree, please let me know. 

Issue History 
Date Modified    Username       Field                    Change               
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2008-12-17 15:43 mvanbaak       Note Added: 0096592                          
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