[dns-operations] "best practices" for restaring internal DNS servers

Rubens Kuhl rubensk at nic.br
Sun Sep 9 13:45:53 UTC 2012

> I'm not sure if I phrased my question correctly. It's not about
> redundancy, but about keeping the queries to root/g(TLD) name servers
> to a minimum.
> In your example, if was the resolver that just came up again
> after a restart, it wouldn't return a failure for a query that it has
> not yet cached. Or perhaps I just didn't understand your answer.

If your recursive DNS server runs Unbound, you can use

unbound-control dump-cache > <filename> 

prior to restarting
and then

unbound-control load-cache < <filename>

I don't recall such an option being available with BIND 9, and it's probably a feature to suggest to BIND 10. 


More information about the dns-operations mailing list