forwarders are unreachable -> lookup fails?

[Brad Knowles]

At 5:33 PM +0000 3/21/01, Jim Reid wrote:

>  Another moral is don't forward if at all possible. Forwarding is evil.
>  Unfortunately it is a necessary evil in some circumstances. Using
>  forwarding to build up a huge cache on one central name server is not
>  a valid justification for forwarding in my opinion.

	Really?  I wasn't aware that you felt this way.

	In my experience, forwarding plus caching has been the only way I 
could guarantee a relatively consistent "one world" view of the DNS 
across all the caching/recursive nameservers I've used, and has been 
the only way I could find that would off-load enough unnecessary work 
so that the central caching nameservers would be able to survive the 
pounding that they would otherwise have taken.

	If you don't mind, I'd be extremely interested to learn as much 
as I could from you as to why you feel that this strategy is a bad 
idea.

>  Correct. The same thing is done in 8.2.3 too. From the CHANGES file:
>
>   997.   [support]       forwarders are now used in order by measured RTT.

	Ahh, okay.  Cool.  I had missed that one.  Thanks!

--
Brad Knowles, <brad.knowles at skynet.be>

/*     efdtt.c     Author:  Charles M. Hannum <root at ihack.net>             */
/*                                                                         */
/*     Thanks to Phil Carmody <fatphil at asdf.org> for additional tweaks.    */
/*                                                                         */
/*     Length:  434 bytes (excluding unnecessary newlines)                 */
/*                                                                         */
/*     Usage is:  cat title-key scrambled.vob | efdtt >clear.vob           */
/*     where title-key = "153 2 8 105 225" or other similar 5-byte key     */

#define m(i)(x[i]^s[i+84])<<
unsigned char x[5],y,s[2048];main(n){for(read(0,x,5);read(0,s,n=2048);write(1,s
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*2-k%8^8,a=0,c=26;for(s[y]-=16;--c;j*=2)a=a*2^i&1,i=i/2^j&1<<24;for(j=127;++j<n
;c=c>y)c+=y=i^i/8^i>>4^i>>12,i=i>>8^y<<17,a^=a>>14,y=a^a*8^a<<6,a=a>>8^y<<9,k=s
[j],k="7Wo~'G_\216"[k&7]+2^"cr3sfw6v;*k+>/n."[k>>4]*2^k*257/8,s[j]=k^(k&k*2&34)
*6^c+~y;}}