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On 8/12/08 12:54, Alain Williams wrote:
<blockquote cite="mid:20081208125421.GH29334@mint.phcomp.co.uk"
type="cite">
<pre wrap="">On Mon, Dec 08, 2008 at 12:43:44PM -0000, John Winters wrote:
</pre>
<blockquote type="cite">
<pre wrap="">Interesting idea. Isn't there (wasn't there?) a requirement to have a
secondary as well as a primary?
</pre>
</blockquote>
<pre wrap=""><!---->
Yes there is.
It is a good idea because there are some crappy MTAs that bounce mail
after a very short time if they can't get through -- which could happen if
your main MX is offline for whatever reason.
</pre>
</blockquote>
<br>
If there are any such MTAs, I don't think there's enough of them to
warrant worrying.<br>
<br>
There's no requirement to run a secondary MX -- I looked after a large
ISP's MTA infrastructure for about eight years and we only ever had a
single MX record. At the end of that period it was processing about
seven million messages / day; of course, that single record responded
to a farm of about half a dozen physical servers.<br>
<br>
Secondaries are targetted by spammers for reasons including what the OP
described.<br>
<br>
Luke<br>
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