In message <20160220172148.ga26...@fantomas.sk>, Matus UHLAR - fantomas writes: > On 19.02.16 17:08, blrmaani wrote: > >We have a DNS setup where we forward a name in one domain to 5 external > > nameservers. We see NXDOMAIN error intermittently (once in couple of > > weeks). How do I debug this issue? > > tcpdump? > > >I took a cache dump on our DNS and 2 out of 5 nameserver IPs appear in "Unas > sociated entries" when the problem happens. > > anything more isble in the cache? > > last time I have encountered this error, it was problematic Cisco DNS load > balancer, responding NXDOMAIN to a PTR (and possibly other) type queries, > while standard types returned proper answer.
Or using "forward first;" rather that "forward only;" and falling back to the Internet and getting NXDOMAIN there. > -- > Matus UHLAR - fantomas, uh...@fantomas.sk ; http://www.fantomas.sk/ > Warning: I wish NOT to receive e-mail advertising to this address. > Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu. > The only substitute for good manners is fast reflexes. > _______________________________________________ > Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe > from this list > > bind-users mailing list > bind-users@lists.isc.org > https://lists.isc.org/mailman/listinfo/bind-users -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: ma...@isc.org _______________________________________________ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users