Separating multiple domain addresses

[frottola]

I'm very new at this. We host multiple domains. Right now, if someone sends mail to username@domain.com, if there is a user with that name in any of the other domains we host, they will get this mail. How do I change this so that a sender has to send to the username at their domain, and all others will bounce.

There is currently a rule in our virtusertable:
$1@domain.com @domain.com

Is this what's controlling this? If not, what is $1 (I've only ever seen %1).

Thanks.

 

[charlesguy]

Yes, you should let your aliases file take care of the issue but maybe there is some unique reason why the previous person put it like that. Take it out and see what happens