Re: [SLUG] Secondary MX record - To have or not

["Oscar Plameras" <oscarp@xxxxxxxxxxx>]

The most important reason for having a second, etc
MX record is,

When the primary mail server is down, incoming mail
will not bounce in the meanwhile. So, when the faulty
mail server is up the seconday server may immediately drain
the queued messages to the mail server or servers without
any users noticing the lack of service. Perhaps, only delayed
delivery.

For this reason secondary MX are imperative.

Better if you have more depending on the number
of mail clients. 

>From my experience optimum is,

up to 500     users-  2 MX
up to 1000   users-  3 MX
up to 3000   users-  4 MX
up to 8000   users-  5 MX
up to 15000 users- 6 MX
......
......
up to 60000 users- 10 MX

From: "Matt Hyne" <mhyne@xxxxxxxxx>

> Folks, 
> 
> A little Linux unrelated (but I suppose it is since I am using a Linux
> server) but I have been having some discussions with a number of vendors
> around the place regarding secondary MX records.
> 
> There seems to be two camps here - those that do not believe that they
> are needed (and thus don't provide them) and those that believe that
> they are a mandatory part of a redundant mail system.
> 
> I am sitting on the fence (I can see some merits to both sides of the
> argument) but I was wondering what the opinion of the sluggers out there
> is - would you install one and why ?
> 
> Matt
> 
> -- 
> SLUG - Sydney Linux User's Group - http://slug.org.au/
> More Info: http://lists.slug.org.au/listinfo/slug