Recursive bind becomes unresponsive with high load

[Tony Finch]

sthaug at nethelp.no <sthaug at nethelp.no> wrote:
>
> Have you checked your operating system limits? One recursive client
> often means one open socket (waiting for response from authoritative
> server), i.e. one open file descriptor. If you have thousands of
> simultaneous recursive clients, you will need a correspondingly large
> file descriptor limit for the named process.

The other problem you might run into is lack of TCP ephemeral ports, due
to TIME_WAIT. But if this is a local zone you should be able to ensure
that your authoritative and recursive servers stay on UDP to avoid this
problem. (e.g. set minimal-responses on the auth server)

Tony.
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