How to relay all local mail to External smtp

[amsharma]

Hello,

I have used an old How to "Installing A LAMP System With Fedora Core 6". As its stable I haven't touched it. I would like Postfix to send out ALL emails including Local ones to the main smtp server of the domain. I have used a RelayHost but the local email gets delivered locally. My server name is compmail.mydomain.com. My web and email server is mydomain.com. I checked a lot on the Net but could not find any concrete solutions. Will changing my machine name to compmail.localdomain.com etc would help.

As users are geographically spread out I would like them to see all emails on the Webmail. This doesn't happen. Can anybody suggest a solution.

Thanks
Amal