procmail

Hi All,
I want to write a recipient for procmail to disable mail delivery to
users from all domains except three.
Like I have a mail server where I have around 100 users, I want all of
them
to receive what ever mail comes from gmail.com, yahoo.com and
rediff.com
but any mail comes from any other domain should not delivered to any
users, instead all of them should go to mailbackup@....
Any help

Regards,

Suvo

suvo wrote:
> Hi All,
> I want to write a recipient for procmail to disable mail delivery to
> users from all domains except three.
> Like I have a mail server where I have around 100 users, I want all of
> them
> to receive what ever mail comes from gmail.com, yahoo.com and
> rediff.com
> but any mail comes from any other domain should not delivered to any
> users, instead all of them should go to mailbackup@....
> Any help

The place to do this is on your MTA (sendmail, postfix, whatever).