Maintenance completed.

DNS resolution performance should now be improved for apartments using our DNS resolvers.

The DNS servers are also more resilient against slow or unresponsive authoritative DNS servers.

PTR zones and gateway PTR records have been added for all apartment site prefixes. This allows reverse DNS lookups within those prefixes to return proper authoritative answers, including cacheable negative responses for IPs without PTR records (NXDOMAIN).

Achieved:

fewer SERVFAILs
fewer retries
better negative caching
better behavior when external authoritative servers are slow

Apartment DNS NS1 and 2 are being optimized for faster resolution speeds. The disturbance to current traffic and downtime is expected to be minimal to none, with the only noticeable effect during the maintenance being websites loading a few msec slower.

Also includes configurations for resilience, when other authoritative servers are slow/unreachable.