How to Set Up Exim to Forward Mail

centosemailexim

I'm trying to setup Exim on a fresh CentOS install so that it will receive mail for a collection of given addresses, and forward the mail respectively to another address. For example, receiving mail from me@example.com would be forwarded to me@gmail.com.

I figure this should be fairly straight forward… I had this working before with Sendmail, using the virtusertable – is there something similar I can do with Exim?

I'd also like to be able to send mail, but only for mail being sent from the local machine (i.e., from applications running on the server) – I don't need/want a publicly available SMTP server.

Are there any other settings I should bear in mind to make sure the mail server is secure? (i.e., prevent relaying) I'm assuming that it will be secure out of the box.

Thanks.

Best Answer

You will need to use a redirect router. Read the Exim Router specification, as it can do many things and thus can get quite complex.

Basically, you will need to set something up like this (untested)


sender_redirect:
  driver = redirect
  data = ${lookup{$sender_address}lsearch{/etc/exim4/sender_redirects}}

Then create a file in /etc/exim4/sender_redirects that contains the redirects in a line-separated colon-delimited format, like this:


me@example.com: me@gmail.com

Related Solutions

Exim Sendmail Configuration – Relay Setup Guide

In the routers section of your exim config, you'll have a router that looks something like this:

 lookuphost:
    driver = lookuphost
    transport = remote_smtp

This is what tells exim to deliver mail directly. You need to tell it to use the smarthost instead.

Replace the above router with something like this:

 smarthost:
   driver = manualroute
   domains= ! +local_domains
   transport = remote_smtp 
   route_list = *  smtp.ultrahosting.com  byname
   host_find_failed = defer
   no_more

Make sure that the transport name in the new router is the same as in the original (remote_smtp in this example).

Also, you'll need to restart exim after making these changes.

Ubuntu – Confusion when configuring exim or postfix

This isn't a direct answer to your question, however it might be the ultimate answer. Something you said piqued my curiosity:

This is a web server, and I simply want it to be able to send mail.

This all depends on how you want mail to be sent. If you're using a CMS or developing you're own application, virtually all languages have SMTP functions that can send mail without using a local MTA. Only install a full MTA if you have a verifiable reason to.

Best Answer

Related Solutions

Exim Sendmail Configuration – Relay Setup Guide

Ubuntu – Confusion when configuring exim or postfix

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