[Dnsmasq-discuss] Query forwarding behaviour with multiple name servers.

[Kevin Darbyshire-Bryant]

Aha! I know this (it’s a Unix system… /<JURASSIC PARK>)

> On 8 Feb 2019, at 09:49, John Robson <jrobson at zenoss.com> wrote:
> 
> Hi all,
> 
> I'm trying to understand the mechanism by which dnsmasq uses the resolvers specified (in this case they are all specified in /etc/resolv.conf).
> Specifically I am trying to work out why dnsmasq is (erratically) sending the same query to multiple servers, and not listening beyond the first response.
<snip>
> Two questions:
>  - What triggers dnsmasq to forward a query to multiple upstream resolvers (aside from the first query after startup, which seems reasonable)

From src/config.h
#define FORWARD_TEST 50 /* try all servers every 50 queries */
#define FORWARD_TIME 20 /* or 20 seconds */

The thread http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2018q2/012226.html

>  - Why does dnsmasq not bother to listen for the second (or more) response - which would surely be useful in terms of timing/aliveness information, as well as less odd for the upstream server*.

Now that I cannot answer.


Cheers,

Kevin D-B

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