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Hello,<br>
<br>
A new <b>DNS_CACHE</b> module has been added to OpenSIPS trunk, and
it will also be present in the future 1.8 release.<br>
<br>
In the current OpenSIPS design, I/O Operations, DNS included, are
done in a blocking way, with the SIP workers having to wait for the
DNS query to return, until further processing can be done. Slow DNS
servers are often a source of performance degradation, and DNS
queries that are not resolvable have an even larger performance
impact.<br>
<br>
The new <b>DNS_CACHE</b> module implements the Key-Value Interface
[1] to allow caching of DNS records in a user-chosen back-end (
local cache, memcached, etc. ) for the TTL number of seconds
returned in the DNS response, thus greatly improving the speed of
subsequent DNS requests for the same domain. Failed queries (
without any records found in DNS ) are also cached with a
user-chosen duration.<br>
<br>
For a full documentation of the module, visit [2] .<br>
Testing and feedback is very much welcomed.<br>
<br>
[1] <a class="moz-txt-link-freetext"
href="http://www.opensips.org/Resources/DocsTutKvinterface">http://www.opensips.org/Resources/DocsTutKvinterface</a><br>
[2] <a class="moz-txt-link-freetext"
href="http://www.opensips.org/html/docs/modules/devel/cachedb_cassandra.html">http://www.opensips.org/html/docs/modules/devel/dns_cache.html</a><br>
<br>
Regards,<br>
<pre class="moz-signature" cols="72">--
Vlad Paiu
OpenSIPS Developer
<a class="moz-txt-link-freetext" href="http://www.opensips-solutions.com">http://www.opensips-solutions.com</a> </pre>
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