[Dnsmasq-discuss] DNS/host lookup delay, how to diagnose?

Chris Green cl at isbd.net
Thu Feb 20 09:54:44 GMT 2020


On Thu, Feb 20, 2020 at 09:22:05AM +0000, Chris Green wrote:
> > P.S.
> > Here is assumed that original poster found in manual page:
> > 
> >   --log-queries
> >           Log the results of DNS queries handled by dnsmasq.
> 
> Yes, thanks, I'll be trying that but I wasn't sure how much timing
> information it would provide.
> 
Here is the result of a query that took 5 seconds in 'host':-

    Feb 20 09:24:05 newdns dnsmasq[465]: 15 192.168.1.92/52420 query[A] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:05 newdns dnsmasq[465]: 15 192.168.1.92/52420 /etc/hosts esprimo.zbmc.eu is 192.168.1.3
    Feb 20 09:24:06 newdns dnsmasq[465]: 16 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 16 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 17 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 17 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 18 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 18 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 19 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 19 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 20 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 20 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 21 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 21 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 22 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 22 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 23 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 23 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 24 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 24 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 25 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 25 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 26 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 26 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 27 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 27 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 28 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 28 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 27 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 28 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 28 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 29 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 29 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 30 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 30 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 31 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 31 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 32 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 32 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 33 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 33 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 34 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 34 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 35 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 35 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 36 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 36 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 37 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 37 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 38 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 38 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:06 newdns dnsmasq[465]: 39 192.168.1.92/52342 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:06 newdns dnsmasq[465]: 39 192.168.1.92/52342 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:11 newdns dnsmasq[465]: 40 192.168.1.92/43165 query[AAAA] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:11 newdns dnsmasq[465]: 40 192.168.1.92/43165 config esprimo.zbmc.eu is NODATA-IPv6
    Feb 20 09:24:11 newdns dnsmasq[465]: 41 192.168.1.92/36962 query[MX] esprimo.zbmc.eu from 192.168.1.92
    Feb 20 09:24:11 newdns dnsmasq[465]: 41 192.168.1.92/36962 config esprimo.zbmc.eu is NODATA

So:-

    Why does the query get repeated so many times?  Is it because the IPV6 is failing and
    it's retrying?

    Why is there that 5 second delay between 40 and 41?  That's presumably the delay I'm
    seeing in the response to the 'host' command.

Thanks for any explanations and help.

-- 
Chris Green



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