dnsdiag/README.md

# dnstools
DNS Diagnostics and Performance Measurement Tools

# prerequisites
This script requires python3 as well as latest [dnspython](http://www.dnspython.org/).
Please note that "dnstraceroute" requires a modified version of dnspython module, which is included. You just need to run `git submodule update --init`

# dnsping
dnsping pings a DNS resolver by sending an arbitrary DNS query for given number of times:
```
% ./dnsping.py -c 3 -s 8.8.8.8 -t MX wikipedia.org

DNSPING 8.8.8.8: hostname=wikipedia.org rdatatype=MX
101 bytes from 8.8.8.8: seq=0   time=161.607 ms
101 bytes from 8.8.8.8: seq=1   time=156.355 ms
101 bytes from 8.8.8.8: seq=2   time=145.201 ms

--- 8.8.8.8 dnsping statistics ---
3 requests transmitted, 3 responses received,   0% lost
min=145.201 ms, avg=154.388 ms, max=161.607 ms, stddev=8.378 ms
```
This script calculates minimum, maximum and average response time as well as jitter

# dnsperf
dnsperf is a bulk ping utility that sends an arbitrary DNS query to a give list of DNS servers. This script is meant for comparing response time of multiple DNS servers at once:
```
% ./dnsperf.py wikipedia.org
server             avg(ms)     min(ms)     max(ms)     stddev(ms)  lost(%)
--------------------------------------------------------------------------
4.2.2.1            151.067     131.270     221.742     28.643      %10
4.2.2.2            142.175     132.921     178.133     13.348      %0
64.6.64.6          133.047     109.145     162.938     20.609      %0
64.6.65.6          377.270     97.669      661.471     172.717     %0
8.8.4.4            389.048     294.581     511.134     67.953      %0
8.8.8.8            0.000       0.000       0.000       0.000       %100
208.67.222.222     179.068     135.975     258.582     50.681      %0
208.67.220.220     137.817     135.822     140.113     1.504       %0
```

# dnstraceroute
dnstraceroute is a traceroute utility to figure out the path that your DNS request is passing through to get to its destination. You may want to compare it to your actual network traceroute and make sure your DNS traffic is not routed to any unwanted path.

```
% ./dnstraceroute.py -s 4.2.2.1 yahoo.com
 dnstraceroute.py 4.2.2.1: hostname=yahoo.com rdatatype=A
 1       192.168.199.57 (192.168.199.57)  47 ms
 2       192.168.198.21 (192.168.198.21)  21 ms
 3       192.168.169.169 (192.168.169.169)  27 ms
 4       192.168.168.137 (192.168.168.137)  28 ms
 5       so-5-0-0.franco71.fra.seabone.net (89.221.34.6)  23 ms
 6       xe-5-3-1.fra44.ip4.gtt.net (89.149.129.185)  62 ms
 7       *  1126 ms
 8       ae-1-60.edge5.Frankfurt1.Level3.net (4.69.154.9)  62 ms
 9       ae-1-60.edge5.Frankfurt1.Level3.net (4.69.154.9)  12 ms
 10      a.resolvers.level3.net (4.2.2.1)  171 ms
```