Intermittent NXDOMAIN for a name we are forwarding

blrmaani blrmaani at
Mon Feb 22 03:07:04 UTC 2016

On Friday, February 19, 2016 at 5:09:02 PM UTC-8, 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?
> I took a cache dump on our DNS and 2 out of 5 nameserver IPs appear in "Unassociated entries" when the problem happens.
> Any advice to troubleshoot this issue is greatly appreciated.
> Thanks
> Blr

the cache dump also has this entry ( is name I am interested in)  10324   \-ANY   ;-$NXDOMAIN

Which probably means if anyone requests for, they will be handed NXDOMAIN for upto 10324 seconds from now..

Our current work around is to restart named (which cache) or we could do a 'rndc flush'. 

Question: Is there a BIND option to say 'Don't cache for NXDOMAIN error code?'

Alternatively, I can have a local query for this and flush cache if error code is NXDOMAIN, but is hacky.. I would like a config option

More information about the bind-users mailing list