Maintained by: NLnet Labs

Unbound 1.6.0rc1 prerelease

Ralph Dolmans
Thu Dec 15 11:19:05 CET 2016


Hi Spike,

On 15-12-16 05:04, Spike wrote:
> thanks for the insight Ralph.
> 
> comments inline below:
> 
> On Mon, Dec 12, 2016 at 2:19 AM Ralph Dolmans via Unbound-users
> <unbound-users at unbound.net <mailto:unbound-users at unbound.net>> wrote:
> 
>     A module (C or Python) can now dictate that the Unbound cache should be
>     bypassed when receiving queries containing the by the module registered
>     EDNS options. This makes the module responsible to do the cache lookup.
>     If you disable cache lookup and don't implement the cache lookup in your
>     module, you wont use any cache at all!
> 
> 
> mmmh, not quite sure I get it. Do you have an example somewhere? right
> now I'm using something very similar
> to https://www.unbound.net/documentation/pythonmod/examples/example2.html .
> 
> Did you mean that somehow I could change that code to ignore the cache?
> I thought that module wasn't called to begin with if the cache had a
> hit, which is my problem to begin with. At the same time I'm not sure I
> wanna run that python script every single request even when there's a
> cache hit available.
> 
> am I making any sense?

The rationale for the module triggered skip cache lookup option is that
there are use cases in which different caches are needed based on the
edns option in the query. The module that dictates the cache bypassing
should cache the answers in some way.

This does not seem to be the case for you. You can do this using local
zones, which are handled before the cache lookup. Also see Wouter's
answer for an example.

Regards,
-- Ralph