Restrict outgoing mails with Zimbra with certain subject line. Possible?

linuxlover.chaitanya · 08-16-2012, 12:52 AM

Hello All,

We are in process of implementing Zimbra as Smart Host for Exchange server we have. It is a free community edition as it will only be used as Smart Host.
What we need is that, when a user tries to send an email using our exchange, Zimbra should check for the subject line, and if that contains certain words, the mail should be rejected and not sent outside.
Is there a way to configure Zimbra MTA to reject outgoing mails based on subject line?

bathory · 08-17-2012, 04:34 PM

Hi,

Well, zimbra uses spamassassin to check mail for spam, so you can configure spamassassin to mark as spam any mail with the said subject.
You can read this to see how to create such a custom rule.
Just make sure that the score you give is above zimbra's kill threshold, so it nukes that mail.

Regards

linuxlover.chaitanya · 08-20-2012, 12:54 AM

Namaste bathory,

Thanks for the cook book. I would like to go through all the links and the documentation in the above link and try all those. As a workaround, I had used rules for dropping all the outgoing mails with certain subject line using Postfix configuration itself. But that is not sooo good idea for as I see, Spam Assassin seems to a be self learning software and this will help a lot.

linuxlover.chaitanya · 08-20-2012, 04:00 AM

One more thing I would like to ask here, is Spam Assassin linked and integrated with IMAP/POP services or even with MTA? The reason I am asking this is, I need to scan outgoing mails as well for spam. I do not intend to use this server for receiving emails.

bathory · 08-20-2012, 04:41 AM

Quote:

Originally Posted by linuxlover.chaitanya

One more thing I would like to ask here, is Spam Assassin linked and integrated with IMAP/POP services or even with MTA? The reason I am asking this is, I need to scan outgoing mails as well for spam. I do not intend to use this server for receiving emails.

Spam filters like spamassassin work with the MTA not with IMAP/POP.
So in zimbra anything you send or receive is passed through spamassassin and then it goes for delivery either locally (incoming mail) or to the destination MTA (outgoing mail)

Regards

linuxlover.chaitanya · 08-20-2012, 04:56 AM

Ohh... thanks for the clarification. I thought Spam Assassin would restrict the mails that are received by Zimbra and it is integrated with Pop or IMAP service.
Thanks for your time and response. I would also like to know if there is any option in Zimbra admin web console where I can see all the deferred mails that are marked as Spam. Or any other spool directory where these spam messages are stored.

bathory · 08-20-2012, 12:46 PM

Quote:

I would also like to know if there is any option in Zimbra admin web console where I can see all the deferred mails that are marked as Spam. Or any other spool directory where these spam messages are stored.

I don't know if you can see the outgoing spam.
There is a queue option in admin console where you can see the deferred or held messages among others, but I don't think it contains the outbound spam mail. That is because if the SA score is above the spam kill limit, mail gets deleted and in other cases it's sent to the recipient.
Maybe you should ask the zimbra forums about this.

linuxlover.chaitanya · 08-21-2012, 08:01 AM

I have tried Zimbra forums a bit but I am not too comfortable with Zimbra forums. Or should I say I do not like them as much as LQ. Most of the answers on Zimbra forums from mods are "Search forums this has been answered so many times" or something similar.
There are lot of questions those have been answered earlier. But people still ask them as they are not able to search.