3938. [func] Added quotas to be used in recursive resolvers
that are under high query load for names in zones
whose authoritative servers are nonresponsive or
are experiencing a denial of service attack.
- "fetches-per-server" limits the number of
simultaneous queries that can be sent to any
single authoritative server. The configured
value is a starting point; it is automatically
adjusted downward if the server is partially or
completely non-responsive. The algorithm used to
adjust the quota can be configured via the
"fetch-quota-params" option.
- "fetches-per-zone" limits the number of
simultaneous queries that can be sent for names
within a single domain. (Note: Unlike
"fetches-per-server", this value is not
self-tuning.)
- New stats counters have been added to count
queries spilled due to these quotas.
These options are not available by default;
use "configure --enable-fetchlimit" (or
--enable-developer) to include them in the build.
See the ARM for details of these options. [RT #37125]
support for addzone/delzone feature (see change
#2930). Removed "new-zone-file" option, replaced
with "allow-new-zones (yes|no)". The new-zone-file
for each view is now created automatically, with
a filename generated from a hash of the view name.
It is no longer necessary to "include" the
new-zone-file in named.conf; this happens
automatically. Zones that were not added via
"rndc addzone" can no longer be removed with
"rndc delzone". [RT #19447]
