Joseph S D Yao jsdy at
Thu Sep 28 18:38:22 UTC 2006

On Thu, Sep 28, 2006 at 08:58:36AM -0700, Dave Stewart wrote:
> On Sep 27, 2006, at 5:13 PM, Joseph S D Yao wrote:
> >
> > On Wed, Sep 27, 2006 at 03:12:49PM -0700, broadcast wrote:
> > ...
> >> Well, I havent used the -4 option, everything seems to be working
> >> properly with the ncache 1 second option.
> >
> >
> > Ah.  Well this is useful feedback.  Thanks.
> Broadcast had mentioned the ncache setting resolved the problem in a  
> previous message, I figured that implied he hadn't tried the -4  
> option (people tend to stop trying things when they stumble upon  
> something that works:). Maybe you missed that Joe.

Yes, I went back and looked, and that was one of two messages in this
thread I had inadvertantly skipped.

> My question as a student of Bind and not an expert is this: is there  
> any "anti-social" behavior occurring because of the ncache being set  
> to such a short time? It would seem to me that this might cause  
> Broadcast's bind server to repeatedly query these bad domains (since  
> the negative response isn't being cached, therefore the domain isn't  
> in the cache ...), increasing traffic. If so, I would guess this can  
> be mitigated against by using the -4 option, reducing DNS noise on  
> Broadcast's servers. Or am I missing something or otherwise making a  
> mountain out of a molehill?

Yes, you are right, which is why this isn't normally set so low.  But
perhaps his DNS server does a small number of queries relative to those
in the world.  And for those who missed it (I know you didn't), positive
answers should still be cached for the full length of time.

Joe Yao
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