When does a BIND DNS server query for the root servers

[Cricket Liu]

> i know, that a BIND DNS server actively queries for the root servers when
> starting up (it tries to get the list of the real root servers, using the
> information present in the root hints as a starting point)
>
> Beside this situation, do you know which (error) condition might also lead
> to the event that BIND will actively query for a list of root servers ?

The TTL on the root NS RRset is six days, so the name server
would need to requery at least that often.

A failure to get a response to its query for the current list
of roots will cause a BIND name server to try other name
servers in the root hints file.  Without Internet connectivity,
you'll see the name server try over and over.

cricket

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