[80580] in North American Network Operators' Group
Re: [dnsop] DNS Anycast revisited (fwd)
daemon@ATHENA.MIT.EDU (Patrick W. Gilmore)
Wed May 4 00:37:11 2005
In-Reply-To: <42783364.2050905@nonexiste.net>
Cc: "Patrick W. Gilmore" <patrick@ianai.net>
From: "Patrick W. Gilmore" <patrick@ianai.net>
Date: Wed, 4 May 2005 00:36:45 -0400
To: nanog@merit.edu
Errors-To: owner-nanog@merit.edu
On May 3, 2005, at 10:28 PM, Nicholas Suan wrote:
> In the previous paragraph Vixie said:
>
>> while i'm on the subject, i also remain convinced that using
>> anycast to do
>> distributed load balancing for applications like WWW, on the
>> assumption
>> that the path you heard a dns query on is instructive as to what
>> content
>> would be best to answer with, is silly, and will more often do
>> harm or do
>> nothing than do good. (and i've told akamai and speedera this
>> many times.)
>> ("but it makes for great marketing slideware.")
>>
>
> In other words this is a bad idea:
>
> [FT@fenrir FT]$ dig a248.e.akamai.net @69.45.79.10
>
> ;; ANSWER SECTION:
> a248.e.akamai.net. 20 IN A 80.67.72.214
> a248.e.akamai.net. 20 IN A 80.67.72.201
>
> FT@inuyasha:~$ dig a248.e.akamai.net @69.45.79.10
>
> ;; ANSWER SECTION:
> a248.e.akamai.net. 20 IN A 69.45.79.15
> a248.e.akamai.net. 20 IN A 69.45.79.16
>
> While I'm not a mind reader, It seems he's saying that, since
> Ultradns doesn't use anycast to do this, it is an example of 'good
> anycast.'
I'm not a mind reader either, but I read English. (Well, I try
sometimes. :) Paul said:
<quote>
i also remain convinced that using anycast to do distributed load
balancing for applications like WWW, ... is silly, and will more
often do harm or do nothing than do good. (and i've told akamai and
speedera this many times.)
</quote>
The fact your digs returned different IPs for the same hostname has
_nothing_ to do with anycast.
Whether (or not) UltraDNS doing this (or not) is good (or not) seems,
to me at least, to be apples & oranges.
--
TTFN,
patrick
