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thomasmerz / dnspingtest_rrd

Monitoring of average response times of DNS resolvers in RRD databases and simple HTML pages with PNG graphs
https://thomasmerz.github.io/dnspingtest_rrd/
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DNS Ping isn't that informative as dig command - big differences occur when selecting dig instead auf ping #8

Open pictosun opened 5 months ago

pictosun commented 5 months ago

Hi,

thanks again for your informative details within all this tests... But after digging a little bit deeper into all this DNS stuff I found out, it's better to check all those DNS servers via 'dig' command instead of ping.

I'm testing all DNS providers via Smokeping and inside of here with ping and dig.

And what I can say is that we can see a big difference between those two.

I do have nearly the same results as you concering ping results... But when changing to dig results you can clearly see a difference! And as dig command is more informative I would really like to see your testings also using the dig command.

thomasmerz commented 5 months ago

Hi @pictosun , thanks for your request - I really like this 👍🏼

I'm trying to figure out how to switch from dnsping to dig. Before going into scripting I saw that dnsping is doing some requests and gives more values:
min, max, avg, … dig only gives me one single value - just be doing some "stockpicking" on some upstream DNS I mostly see that dig is most time the min-time from dnsping:

$PING $tcp -q -c $COUNT -w $DEADLINE -s 127.0.0.1 spiegel.de 2>&1; dig spiegel.de @127.0.0.1 +all|grep Query with PING=/usr/bin/dnsping COUNT=4 DEADLINE=5 tcp=


dnsping DNS: 9.9.9.9:53, hostname: spiegel.de, proto: UDP, rdatatype: A, flags: RD
--- 9.9.9.9 dnsping statistics ---
4 requests transmitted, 4 responses received, 0% lost
min=23.238 ms, avg=34.470 ms, max=46.587 ms, stddev=9.696 ms

;; Query time: 23 msec


When querying my local Pi-hole results differ and are much less precise when it came to response times below 1ms:

dnsping DNS: 127.0.0.1:53, hostname: spiegel.de, proto: UDP, rdatatype: A, flags: RD --- 127.0.0.1 dnsping statistics --- 4 requests transmitted, 4 responses received, 0% lost min=0.603 ms, avg=5.918 ms, max=21.451 ms, stddev=10.356 ms;; Query time: 3 msec

…

dnsping DNS: 127.0.0.1:53, hostname: spiegel.de, proto: UDP, rdatatype: A, flags: RD --- 127.0.0.1 dnsping statistics --- 4 requests transmitted, 4 responses received, 0% lost min=0.613 ms, avg=1.312 ms, max=1.968 ms, stddev=0.749 ms

;; Query time: 0 msec