<p>DNS is a blocking operation. If it takes long to get the reply from the dns server, then the Kamailio worker is blocked. Look on the wiki at the core cookbook, there are several core parameters related to dns, try to adjust them. Also, there are config options of the operating system for dns queries (preferences, timeout), you should check them as well and change the values to fit better your needs.</p>
<p>Now, to clarify, after you get the error message that the domain/hostname cannot be resolved, is Kamailio still not handling SIP requests?</p>

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