lkml.org 
[lkml]   [2001]   [Feb]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: DNS goofups galore...
"Michael H. Warfield" wrote:
>
> On Thu, Feb 08, 2001 at 02:58:30PM -0800, H. Peter Anvin wrote:
> > Followup to: <Pine.LNX.4.10.10102081346001.16513-100000@innerfire.net>
> > By author: Gerhard Mack <gmack@innerfire.net>
> > In newsgroup: linux.dev.kernel
> > >
> > > Thanklfully bind 9 barfs if you even try this sort of thing.
> > >
>
> > Personally I find it puzzling what's wrong with MX -> CNAME at all; it
> > seems like a useful setup without the pitfalls that either NS -> CNAME
> > or CNAME -> CNAME can cause (NS -> CNAME can trivially result in
> > irreducible situations; CNAME -> CNAME would require a link maximum
> > count which could result in obscure breakage.)
>
> It generally forces another DNS lookup. If you do a resolve on
> a name of type=ANY it returns any MX records and A records. If you then
> do a resolve on the MX records, you then get a CNAME and then have to
> add an additional lookup for the CNAME. If you have a lot of MX records
> and not all the servers are "up" that can add up to a significant
> increase in DNS traffic.
>

Wouldn't that be true for any CNAME anyway?

-hpa

--
<hpa@transmeta.com> at work, <hpa@zytor.com> in private!
"Unix gives you enough rope to shoot yourself in the foot."
http://www.zytor.com/~hpa/puzzle.txt
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:12    [from the cache]
©2003-2011 Jasper Spaans