[dns-operations] forwarding to a forwarder

[Doug Barton]

On 1/17/2016 8:43 PM, Randy Bush wrote:
> A is a bind 9 where foo.bar is forwarded to B
> can an unbound on C forward foo.bar to A?

Yes. The only disadvantage to this configuration is that you get 
double-caching, so on average you'll have a full TTL period for a change 
to make it all the way back to C. For this reason I always recommend 
slaving instead of forwarding, but when that's not possible this is the 
next-best solution.

> [ A has approval from B.  but C is a hidden server which can not
>    forward to B directly ]

Yeah, when I was with BlueCat I had customers with this exact issue.

hope this helps,

Doug