The current serve-stale implementation in BIND 9 stores all received
records in the cache for a max-stale-ttl interval (default 12 hours).
This allows DNS operators to turn the serve-stale answers in an event of
large authoritative DNS outage. The caching of the stale answers needs
to be enabled before the outage happens or the feature would be
otherwise useless.
The negative consequence of the default setting is the inevitable
cache-bloat that happens for every and each DNS operator running named.
In this MR, a new configuration option `stale-cache-enable` is
introduced that allows the operators to selectively enable or disable
the serve-stale feature of BIND 9 based on their decision.
The newly introduced option has been disabled by default,
e.g. serve-stale is disabled in the default configuration and has to be
enabled if required.
(cherry picked from commit ce53db34d6)
these keywords were added to the parser as synonyms for "master"
and "slave" but were never hooked in to the configuration of named,
so they were ignored. this has been fixed and the option is now
checked for correctness.
(cherry picked from commit ba31b189b4)
With netmgr we're creating separate socket for each IPv6 interface,
just as with IPv4 - update documentation accordingly.
(cherry picked from commit 6a2100034b)
The release notes were previously built as a separate document
(including the PDF version). It was agreed that this doesn't make much
sense, so the release notes are now included only as an appendix to the
BIND 9 ARM.
(cherry picked from commit 8eb2323ec3)
When we made BIND 9 libraries private to BIND 9, we forgot to remove the
libdns section on "export" libraries from the ARM.
(cherry picked from commit 3637c466c9)
This includes reorganization of the lists of RFCs supported by BIND 9.
I included all the RFCs and notes from the list identified by Vicky in
any DNS-related RFCs written by current ISC engineers, on the assumption
that BIND would comply with them.
(cherry picked from commit 8ca7f22671)
Originally, the default value for max-stale-ttl was 1 week, which could
and in some scenarios lead to cache exhaustion on a busy resolvers.
Picking the default value will always be juggling between value that's
useful (e.g. keeping the already cached records after they have already
expired and the upstream name servers are down) and not bloating the
cache too much (e.g. keeping everything for a very long time). The new
default reflects what we think is a reasonable to time to react on both
sides (upstream authoritative and downstream recursive).
(cherry picked from commit 13fd3ecfab)
The ARM and the manpages have been converted into Sphinx documentation
format.
Sphinx uses reStructuredText as its markup language, and many of its
strengths come from the power and straightforwardness of
reStructuredText and its parsing and translating suite, the Docutils.
(cherry picked from commit 9fb6d11abb)
