Handling mobile users

Steve Freegard steve.freegard at fsl.com
Thu Dec 11 10:32:08 GMT 2008

Nigel Kendrick wrote:
> Hi,
> Any hints on handling mobile users where the sending domains keep 
> hopping on and off RBLs? I have asked this before but not really found a 
> satisfactory solution - for example, whitelisting our domain opens up 
> the spam floodgate. The ideal situation would be to skip RBL checks on 
> emails from authenticated users, but either I am not doing it right or I 
> am missing the trick. It was suggested that whitelisting would 
> help but this does not seem to be the case. Our mobiles are on UK 
> Vodafone but, for example, one of the Directors is currently roaming in 
> Italy.
> I was looking at creating up a ruleset for the "Spam List = " to set it 
> to "" for emails from our domain (not ideal, but better than nothing), 
> but I cannot work out how to do this for selected domains.
> All hints and pointers appreciated.

The 'Spam Domain=' list in MailScanner is pretty basic - you'd have to 
write a CustomFunction on it to parse the received headers inserted by 
your MTA and bypass it if the user were authenticated.

I personally wouldn't do it that way - if I were you I would nuke the 
Spam Domain list entirely and configure your MTA to reject clients 
listed on zen.spamhaus.org at RCPT TO: time (e.g. delay checks), then 
your MTA can allow SMTP AUTH clients to send mail regardless of the RBL 
status of their IP address.

That will achieve what you need and reduce the load on your MailScanner 
box at the same time.


More information about the MailScanner mailing list