2016-02-03 11:01:11 +03:30
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# dnstools
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DNS Diagnostics and Performance Measurement Tools
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2016-04-08 12:12:09 +04:30
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==================================================
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2016-02-03 22:48:40 +03:30
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2016-04-08 12:12:09 +04:30
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Ever been wondering your ISP is messing with your DNS traffic? Ever observed
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any misbehavior with your DNS responses? Ever been redirected to wrong address
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and suspected something is wrong with your DNS?
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2016-04-08 10:29:49 +04:30
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Here we have a set of tools to perform basic tests on your DNS requests and responses.
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2016-04-08 12:12:09 +04:30
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You can measure the response time of any given DNS server for arbitrary requests
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using `dnsping`. Just like traditional ping utility, it gives you similar
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functionality for DNS requests.
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You can also trace the path your DNS request takes to destination to
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make sure it is not being redirected or hijacked. This can be done by comparing
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different DNS queries being sent to the same DNS server using `dnstraceroute`
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and observe if there is any difference between the path.
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`dnsperf` helps you choose the best DNS server for your network. While it is highly
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recommended to use your own DNS resolver and never trust any third-party DNS server,
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but in case you need to choose the best DNS forwarder for your network, `dnsperf`
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lets you compare different DNS servers from performance (latency) and reliability
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(loss) point of view.
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2016-04-08 10:29:49 +04:30
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2016-02-06 09:36:01 +03:30
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# prerequisites
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2016-04-07 14:23:28 +04:30
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This script requires python3 as well as latest [dnspython](http://www.dnspython.org/).
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2016-04-08 12:12:09 +04:30
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Please note that "dnstraceroute" requires a modified version of dnspython module,
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which is included. You just need to run `git submodule update --init`
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2016-02-03 22:48:40 +03:30
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2016-02-06 11:55:38 +03:30
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# dnsping
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dnsping pings a DNS resolver by sending an arbitrary DNS query for given number of times:
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```
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% ./dnsping.py -c 3 -s 8.8.8.8 -t MX wikipedia.org
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DNSPING 8.8.8.8: hostname=wikipedia.org rdatatype=MX
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101 bytes from 8.8.8.8: seq=0 time=161.607 ms
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101 bytes from 8.8.8.8: seq=1 time=156.355 ms
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101 bytes from 8.8.8.8: seq=2 time=145.201 ms
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--- 8.8.8.8 dnsping statistics ---
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3 requests transmitted, 3 responses received, 0% lost
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min=145.201 ms, avg=154.388 ms, max=161.607 ms, stddev=8.378 ms
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```
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This script calculates minimum, maximum and average response time as well as jitter
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# dnsperf
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2016-04-08 12:12:09 +04:30
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dnsperf is a bulk ping utility that sends an arbitrary DNS query to a give
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list of DNS servers. This script is meant for comparing response time of
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multiple DNS servers at once:
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2016-02-06 11:55:38 +03:30
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```
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% ./dnsperf.py wikipedia.org
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2016-02-10 09:25:17 +03:30
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server avg(ms) min(ms) max(ms) stddev(ms) lost(%)
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--------------------------------------------------------------------------
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4.2.2.1 151.067 131.270 221.742 28.643 %10
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4.2.2.2 142.175 132.921 178.133 13.348 %0
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64.6.64.6 133.047 109.145 162.938 20.609 %0
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64.6.65.6 377.270 97.669 661.471 172.717 %0
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8.8.4.4 389.048 294.581 511.134 67.953 %0
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8.8.8.8 0.000 0.000 0.000 0.000 %100
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208.67.222.222 179.068 135.975 258.582 50.681 %0
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208.67.220.220 137.817 135.822 140.113 1.504 %0
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2016-02-06 11:55:38 +03:30
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```
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2016-04-07 14:23:28 +04:30
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# dnstraceroute
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2016-04-08 12:12:09 +04:30
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dnstraceroute is a traceroute utility to figure out the path that your DNS request is
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passing through to get to its destination. You may want to compare it to your actual
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network traceroute and make sure your DNS traffic is not routed to any unwanted path.
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2016-04-07 14:23:28 +04:30
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```
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% ./dnstraceroute.py -s 4.2.2.1 yahoo.com
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dnstraceroute.py 4.2.2.1: hostname=yahoo.com rdatatype=A
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1 192.168.199.57 (192.168.199.57) 47 ms
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2 192.168.198.21 (192.168.198.21) 21 ms
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3 192.168.169.169 (192.168.169.169) 27 ms
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4 192.168.168.137 (192.168.168.137) 28 ms
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5 so-5-0-0.franco71.fra.seabone.net (89.221.34.6) 23 ms
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6 xe-5-3-1.fra44.ip4.gtt.net (89.149.129.185) 62 ms
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7 * 1126 ms
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8 ae-1-60.edge5.Frankfurt1.Level3.net (4.69.154.9) 62 ms
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9 ae-1-60.edge5.Frankfurt1.Level3.net (4.69.154.9) 12 ms
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10 a.resolvers.level3.net (4.2.2.1) 171 ms
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```
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