Hello,
I am running across the same issue as described here:
http://lists.sip-router.org/pipermail/sr-users/2015-February/086796.html
Was there a resolution to this issue? I come across this issue fairly regularly. Unlike the OP, however, I do not have any luck by retrying my query: when I place my http_query within a while loop and keep 1-second delays between calls, all consistently fail with error 28. After long pauses, http_query()s start to work as expected.
I think that previous thread mentions DNS as a possible culprit. Is http_query using libcurl's preferred resolver, or is it using Kamailio's built-in DNS cache? I really doubt my local resolver is cause of the issue here.
Any insight is appreciated. Thanks!
Armen