Registry Tip : DNS server may stop resolving domain names for which it is not authoritative.
DNS Server May Write Back Incorrect Root Hints, NS and A records
When a DNS server boots, it needs a list of root server "hints" -- NS and A
records for the servers -- historically called the cache file. Traditionally DNS
administrators could keep this file current by downloading a new copy from the
InterNIC. This method works adequately when the root servers stay fairly static,
but does require attention on the part of the administrator when updates and
changes are made: Q195811