> On Sep 22, 2016, at 7:01 AM, BONUMAHANTI, RAJENDRA KISHORE <rb3...@att.com> > wrote: > > Hi, > > I am testing collapsed_forwarding plugin > (https://docs.trafficserver.apache.org/en/latest/admin-guide/plugins/collapsed_forwarding.en.html?highlight=collapsed_forwarding) > via ATS 6.2.x branch. > > We observed an error "DNS error 2 for [testurl.com]" for cache-miss, when > remap.config is configured with "collapsed_forwarding" to work alone as a > remap plugin. We must modify TSRemapDoRemap() in the plugin to "return > TSREMAP_NO_REMAP" to allow DNS lookup successful. It does not seem right for > the plugin to do "return TSREMAP_NO_REMAP" when it did not.
Yes, this is a bug. Can you file a bug at https://issues.apache.org/jira/browse/TS, and make a github pull request with your fix? > > Can someone help me to understand how this plugin needs to be used? Or does > it require the fix I mentioned above? > > Regards, > Kishore > > == Sample remap.config entry and cach miss error when used > "collapsed_forwarding" by itself == > map http://testurl.com/ http://origin.com/ @plugin=collapsed_forwarding.so > @pparam=--delay=10 @pparam=--retries=5 > > I observed that during cache-miss, DNS query happens on the 'from' url > (hostname) in the remap and it gets failed. > .... > [Sep 9 19:39:16.355] Server {0x2b170ea6c940} DEBUG: (dns) send query > (qtype=1) for testurl.com to fd 43 > [Sep 9 19:39:16.355] Server {0x2b170ea6c940} DEBUG: (dns) sent qname = > testurl.com, id = 9287, nameserver = 1 > [Sep 9 19:39:16.355] Server {0x2b170ea6c940} DEBUG: (dns) sent_one: > failover_number for resolve 1 is 1 > [Sep 9 19:39:16.628] Server {0x2b170ea6c940} DEBUG: (dns) received packet > size = 52 > [Sep 9 19:39:16.628] Server {0x2b170ea6c940} DEBUG: (dns) round-robin: > nameserver 1 DNS respons code = 0 > [Sep 9 19:39:16.628] Server {0x2b170ea6c940} DEBUG: (dns) received rcode = 2 > [Sep 9 19:39:16.628] Server {0x2b170ea6c940} DEBUG: (dns) DNS error 2 for > [testurl.com] > [Sep 9 19:39:16.628] Server {0x2b170ea6c940} DEBUG: (dns) doing retry for > testurl.com > > I further looked in to the code and found that it is due to return code from > the plugin is TSREMAP_DID_REMAP in TSRemapDoRemap(). It makes ATS not to > perform remap. > >
