DNS blocked for private addresses?

[#1]

Quote from: RoBorg

Can anyone from Plusnet confirm that 192.168 addresses are blocked from resolving

Our caching servers will not resolve a hostname pointing to private address space. As others have alluded to, it's not particularly good practice to do this anyway.

[#2]

I may have to reconsider my cache forwarding options 

[#3]

Unbound can be configured to not resolve private ip addresses.