NS
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... DNS
resolution process. The server is capable of returning a different
set of A, NS or CNAME records based on user defined policies,
metrics, or a combination of both. In [11 ...
... DNS servers
in a single DNS resolution is the use of NS and CNAME records. An
example would be the case where a higher level DNS server ...
... NS Redirection ...
... domain might be a
Request-Routing NS server. In this case the Request-Routing DNS
server can either return a set of A records ...
... resolution of the request a.b.example.com to the DNS server that is
authoritative for example.com using NS records.
One drawback of using NS ...
... NS records.
One drawback of using NS records is that the number of
Request-Routing DNS servers ...
... of the entire resolution process. Basically, the last DNS server can
return in the authoritative section of its response its own NS
record. The client will use this cached NS ...
... NS
record. The client will use this cached NS record for further
request resolutions until it expires.
...
... Another drawback is that some implementations of bind voluntarily
cause timeouts to simplify their implementation in cases in which a
NS level redirect points to a name server for which no valid A record ...
... DNS timeouts to occur while
handling exceptional situations. For example, timeouts can occur
for NS redirections to unknown domains.
...