Re: virus mail ignores MX?

[Pierre-Yves Bonnetain <py.bonnetain () ba-cst com>]

Hi,

> some virus mails are filtered well at viruswall.
> but other virus mails are not get through viruswall,
> and go directly to mail.xxxxx.com. I think.
>
> so I think some virus mail ignores MX, right?
>
> What's the problem and how can I solve this problem?

You are right. Some virus (and spam senders) go for the secundary MXes
instead or the primary. You cannot do anything against that (except
using only one primary MX, of course) since this choice is made on the
sender's side.
The best thing to do, whenever you have several MXs, is to have
functionally identical systems, with the same configuration, tools, etc.
That way, whatever the path followed by some mail, it will go through
the same checks. Your current configuration is, in this regard, totally
unsecure since it's very easy to bypass your virus filters.

Hth,

-- 
Pierre-Yves Bonnetain
B&A Consultants - Se'curite' informatique - www.ba-cst.com
Tel. : +33 (0) 563 277 241 - Fax : +33 (0) 563 277 245

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