2011/6/9 Alex Hermann alex@speakup.nl:
The way I read rfc2915, there is no failover mechanism. The application pick the first target that it supports and uses that. There is no mention of trying other records afterwards. Matching/finding NAPTR records stops once the first match is completed. All other records are discarded. From section 2:
Hi Alex, two comments:
1) What you say does not explain my issue (as in any case TLS or TCP have more priority in my NAPTR's than UDP). In fact, my exact problem is that my Kamailio is not performing NAPTR query.
2) About your quoted text, indeed RFC 2915 says that. But that just means that, an application (in this case a SIP client) must take *first* the valid NAPTR record with better "order" (lowest value). But RFC 2915 is just about NAPTR, it can not mandate that applications or protocols cannot try other NAPTR records as failover mechanism. Any SIP client or proxy implementing NAPTR records does failover to the next NAPTR record in case the first one failed (at least those I've tested).
But anyhow, my main problem is that my Kamailio is not performing NAPTR query :)
Cheers.