Introduction
If you want or need to setup your mailserver to send all outgoing mail to a specific server which will handle the delivery to the recipients you need to setup a SMTP relay or smarthost.
Prerequisites
- You need to know the hostname of the SMTP server which is going to relay the mail for your mailserver, which is smtprelay.snel.com in our case
- This article assumes that no authentication is necessary on the SMTP relay server
- This article is written for DirectAdmin with Exim
- You need to have the SSH login details of your server ready
Step 1) Login with SSH
Login as root. Please see this article for instructions if you don't know how to connect.
Step 2) Configure the MTA
Open the configuration file of exim with your favourite text-editor:
nano /etc/exim.conf
Find the following lines:
lookuphost: driver = dnslookup domains = ! +local_domains ignore_target_hosts = 127.0.0.0/8 condition = "${perl{check_limits}}" transport = remote_smtp no_more
Change to:
smart_route: driver = manualroute domains = ! +local_domains ignore_target_hosts = 127.0.0.0/8 condition = "${perl{check_limits}}" route_list = !+local_domains relay.mailchannels.net::587 transport = remote_smtp
Save and exit with CTRL+X.
Step 3) Restart the mailserver
Restart the mailserver by issuing the following command:
service exim restart