-
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.
ce53db34