The crl_dnsstat application watches for DNS queries on UDP port 53 and
counts numbers of messages and numbers of queries, aggregated by any of
source IP, destination IP, opcode, query type, query class.  The subjects
of queries are never recorded.  The example output below shows the finest
aggregation (most detail) it is capable of recording; command line options
can be used to reduce the detail.  The "notes" column displays any unusual
statisitcs:  the number of messages that contained multiple queries or zero
queries, and the number of messages for which the number of queries was
impossible to determine.
<p>
Example output, with source IP addresses changed for privacy:

<pre>
# dnsstat output version: 0.1

# begin trace interval at 965767315.016479, duration 60.000000
# DNS messages: 155056 (2584.266667/s); DNS queries: 969271 (16154.516667/s)

#src             dst              op type  class queries    msgs notes
 7.9.5.56        192.5.5.241       - -     -          36      36
 7.9.5.56        192.5.5.241       0 PTR   IN          8
 7.9.5.56        192.5.5.241       0 A     IN         28
 2.2.6.38        192.5.5.241       - -     -           8       8
 2.2.6.38        192.5.5.241       0 MX    IN          2
 2.2.6.38        192.5.5.241       0 A     IN          6
 2.3.6.66        192.5.5.241       - -     -         183     183
 2.3.6.66        192.5.5.241       0 A     IN         97
 2.3.6.66        192.5.5.241       0 PTR   IN         86
 4.8.4.12        192.5.5.241       - -     -           1       1
 4.8.4.12        192.5.5.241       0 A     IN          1
 0.4.2.12        192.5.5.241       - -     -          28      28
 0.4.2.12        192.5.5.241       0 PTR   IN          1
 0.4.2.12        192.5.5.241       0 A     IN         27
 2.8.8.1         192.5.5.241       - -     -          16      16
 2.8.8.1         192.5.5.241       0 A     IN         16
 8.6.3.2         192.5.5.241       - -     -         511     511
 8.6.3.2         192.5.5.241       0 SOA   IN          2
 8.6.3.2         192.5.5.241       0 ANY   IN          1
 8.6.3.2         192.5.5.241       0 A     IN        508
 .
 .
 .
</pre>