[Dnsmasq-discuss] [PATCH] Retry queries only after giving the upstream server some time to respond

[Dominik Derigs]

Hey Simon,

your patch surely makes sense.

On Mon, 2021-04-05 at 21:38 +0100, Simon Kelley wrote:
> Except that this all started because some clients don't retry from the
> same ID/source port and treating them as a new query that can be
> answered when the existing query for the same name completes fails
> because that means dnsmasq never sees retries from this type of client,
> and it relies on those retries to work in the face of packet loss.
> 
> https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2021q1/014697.html

I see. The "misbehaving" clients out there (a) worked pre-2.83 and (b)
we cannot rely on them being "fixed".

I'm intentionally putting the keywords in quotes because of:
On Mon, 2021-04-05 at 21:38 +0100, Simon Kelley wrote:
> What's a "real" retry. I'm not sure there's an RFC that says it has to
> be from the same source port and query-ID, [...]

Too bad, I figured we could keep up with saving some bandwidth but I
can perfectly live with the fact that you consider the timeout I
suggested as a too-risky feature as in it could break user's systems in
ways which are difficult to define.

Unless we could get a retry feature baked into dnsmasq sometime in the
future.

Best regards,
Dominik