Why forwarding is a Bad Thing

[Brad Knowles]

At 3:59 PM -0500 3/22/01, Kevin Darcy wrote:

>  As Jim knows, I happen to advocate the use of wildcard MX records for
>  outbound mail routing in an internal-root context.

	That's one of the only places in which they are appropriate, but 
we don't publicly talk about things like that because so many people 
screw them up and get them wrong, which results in incredibly heinous 
side-effects.

	Now, the use of forwarding in caching name servers goes into the 
same category.


	These things belong in an "Advanced DNS Configuration & 
Administration" book, one that is made available only to people who 
have demonstrated their ability to obtain and retain a clue.  This is 
why I say that "... people (who know who they are) know when they can 
safely violate this rule."

--
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;}}