Serve-expired not working in combination with send-client-subnet ?

George (Yorgos) Thessalonikefs george at
Tue Nov 29 13:36:27 UTC 2022

Hi Marco,

Two things:
- The 'serve-expired-client-timeout:' has no support for the subnet
   module. That means that when the client timeout is reached, Unbound
   will try to find an (expired) answer in the *global* cache and reply
   to the client(s).

- The subnet module has no support for expired answers.

(I believe we need startup warnings and cleaner documentation for those)

So if your answers are stored in the ECS cache, serve-expired logic will 
not be able to find them.
If your answers are stored in the global cache (because based on your 
configuration the upstream has no support for ECS) then serve-expired 
logic will be able to find them after the serve-expired-client-timeout.

Is that what you experience?

Best regards,
-- Yorgos

On 29/11/2022 13:57, Marco Davids (SIDN) via Unbound-users wrote:
> Hello,
> I have an unbound.conf [1] that has both the 'serve-expired'-options and 
> 'send-client-subnet'-options enabled.
> And in that case the serving stale data feature does no longer work.
> Only after I remove the 'send-client-subnet'-lines, the serving stale 
> data functionality is working again.
> Is that a bug or a feature?

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