Author: Stephen Nelson-Smith Date: To: lug, Hampshire LUG Discussion List CC: Subject: Re: [Hampshire] Re: TRYING to set up my own simple mail server? Can
anyone help?
Hi,
> Bind 9 does a fabulous job as a DNS server, with separate views permitted
> for any class of client you may care to specify. It makes much more sense
> than trying to cobble together hosts files all the time.
It really does. Views ftw.
>> Secondly, you appear not to have a backup MX.
>
> This is my only real disagreement with your post - for this scale of
> operation, I really don't think there *should* be a backup MX.
Interesting...
> A backup MX won't get the mail delivered to final recipients any faster -
> they won't be polling it, and they might not have access to it anyway.
> what it will do is to create a false sense that mail has been delivered -
> when in reality it's sat in the backup's spool.
It depends on whether you control the secondary MX. You should. If
you don't you have no control over what gets accepted. That's a Bad
Thing (TM).
> You also need to couple the two MXes quite tightly; if the backup accepts
> mail that can't be delivered, you either need to drop it (with the risk of
> losing mail with typos in the address), bounce it (and become a
> backscatter attackvector), or forward it to someone for manual processing.
> All of these are a problem.
Another problem is the requirement to ensure your spam control on the
backup is tight, as it is often used as a backdoor.
> The effect of not having a backup MX is that mail will sit in the sender's
> spool for a few days. They will probably get a non-delivery warning after
> 4 hours. All these things are the next best thing to actually delivering
> the mail...
Agreed. What I was proposing was not just running one, not very
reliable, mail server.
>> If your mailserver dies, you may
>> lose mail, you will lose time, and cause your company considerable
>> pain.
>
> You will lose time, you will lose access - but you shouldn't actually lose
> any mail.
I've seen it happen - you can lose mail that's still on the spool when
the server dies. Of course a secondary MX won't help here.
>> You could also consider finding someone / some company
>> who will help you set this up, but provide training and documentation.
>> That shares the load, and may get you a more reliable solution. It
>> also means you get to learn "on-the-job" from someone who's done it
>> lots of times before.
>
> I should probably add a disclaimer here: that's now my day job...
