Re: [Sqlgrey-users] Pre Load

[Lionel B. <lio...@bo...>]

Micha Silver wrote the following on 20.01.2007 10:27 :
> I set:
> reconnect_delay = 2
> max_connect_age = 24
> Do you recommend something different?
>   

No, it looks good to me.

> Another question I've been trying to work out: Our ISP serves as a 
> backup MX for our mail domains. How should I handle this as far as 
> greylisting?

Don't use a backup MX if you can't control its own anti-SPAM settings.
With greylisting, this means make them access your greylisting database.
In your case, you'll be better of dropping the backup MX (more on this
later).

>  When sqlgrey sends a 450 response to a new message, the 
> backup MX queues it and does it own retry after a short delay.  Then the 
> message is blocked as spam since the sender addr and IP are the same - I 
> think.

It is blocked by SQLgrey once because the backup MX didn't sent the
message originally (unless there is an awl entry for your backup
already). Then the mail passes on the second try because the backup
should comply with RFCs as a full-fledge MTA. If it is blocked as SPAM,
this is for a reason outside SQLgrey's scope (did you forget to
whitelist your backup MX for some anti-SPAM measure?).

Anyway, just dropping the backup MX should help, its only purpose is to
buffer mails when your server is down (which would happen at the origin
anyway). This (only if configured properly, which means you can trigger
the delivery yourself or your server is constantly monitored by the
backup) can help deliver mails waiting for your server to come back
faster. You are trading a non-measurable and dubious speedup in case of
a crash for more SPAMs in the common case.
This even hides the problem to the sender when your server is down for
an extended period of time (some server are configured to warn the
sender when a mail couldn't reach its destination after a configured
period of time). So the clients/partners/... of your mail user may
discover the problem by phone too late if you are struggling to put
systems back online...

I occasionaly use backup MXs, but only if I'm in control of all of them
and they use a more robust common backend (ie: several cheap pizzaboxes
with good CPUs to handle the computations of clamav and spamassassin,
with a fat system for the storage with big redondant disks, redondant
power and high quality components).

Lionel.