[ratelimits] rate limit counters

[Vernon Schryver]

In the current version of the BIND9 rate limit patch, responses
dropped for rate limiting are counted among "Name Server Statistics"
as "queries dropped".  The `rndc stats` command dumps current
counters to to a file.  If the "statistics-file" option is not used,
the default is named.stats in the server's current directory.

See QryDropped in the discussion of "Statistics Counters" in the ARM
perhaps at
http://ftp.isc.org/isc/bind9/cur/9.9/doc/arm/Bv9ARM.ch06.html#statistics_counters

The QryDropped counter is also incremented for excessive recursive queries
as described in that section and in
http://ftp.isc.org/isc/bind9/cur/9.9/doc/arm/Bv9ARM.ch06.html#clients-per-query


Responses that are "slipped" or answered with a truncated or TC=1
result for rate limiting are included in the RespTruncated counter
with responses that are truncated because they would be too large.


My question is whater that is that good enough?  Must there be
separate counters for responses dropped or truncated for rate
limiting?  My inclination is to say that it is good enough.


Vernon Schryver    vjs at rhyolite.com