NSD does not provide any DNS logging. We believe that this is a separate task and has to be done independently from the core operation. This consciously is not part of NSD itself in order to keep NSD focused and minimise its complexity. It is better to leave logging and tracing to separate dedicated tools.
The CAIDA dnsstat tool can
easily be configured and/or modified to suit local statistics requirements
without any danger of affecting the name server itself. We have run
on the same machine as NSD, and we would recommend using a multiprocessor if
performance is an issue. Of course,
dnsstat can also run on a separate
machine that has MAC layer access to the network of the server.
The nsd-control tool can output some statistics, with nsd-control stats and nsd-control stats_noreset. In contrib/nsd_munin_ there is a Munin grapher plugin that uses it. The output of nsd-control stats is easy to read (text only) with scripts. The output values are documented on the nsd-control man page.
Another available tool is dnstop, which displays DNS statistics on your network.