DNS lookups take too long if not cached

[stepansae]

Hi All,

OS X Server 10.4.8, BIND 9.2.2

I’m experiencing rather long delays when looking up internet IPs. Sometimes the lookup takes almost 10 seconds when the record is not cached. Once it is in the cache, it is translated instantly. Local zones names are fast enough too.

Any ideas how to optimize this?

I was advised that there might be a sort of timeout settings – wait some time before you ask another DNS. But this theory doesn’t seem right to me, nor I was able to find any such thing in BIND documentation.

I was also thinking – during the installation of DNS in OS X you don’t have to specify any forwarding servers. Is it possible that there is one standard DNS preconfigured by Apple which is quite overloaded, causing the delays? If so, where would one change these servers?

Many thanks,

Stepan

[stepansae]

coincidently, apple has released 10.4.9 server update yesterday. BIND was updated to 9.3 and update description stated that unusually long lookup times have been fixed …

I did update and my issue gone better … but I’m still not happy, I’m still looking into the way how to change NS to those provided by my ISPs ….

[stepansae]

This really did not make much difference, but at least now I know more about the BIND on OS X.

What made another huge difference was update on my other OS X DNS servers (forwarders) and then after 2 days the performance shoot up.

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