Every JumpBox is configured to deliver email just like any other mail server on the internet. Users may run into trouble when using a JumpBox on a local network that is connected to the internet through a cable modem or DSL connection. Some mail servers (like Gmail) may not accept email from hosts using these types of connections. In these cases, your ISP may provide an SMTP relay server that you can configure your JumpBox to use.
Configuring Outbound Email on a 1.1+ JumpBox
The JumpBox Administration Portal can now configure an unauthenticated SMTP/Mail relay for you. Please see the JumpBox Mail Relay Configuration Tutorial.
We do not yet have a convenient way to set up authenticated mail relays. Registered users should be able to manually configure Postfix to do this. See the Postfix Documentation for details.
Configuring Outbound Email on a 1.0 JumpBox
To configure your JumpBox to send mail through an SMTP relay server you will have to register your JumpBox and enable shell access then SSH to your JumpBox as the 'admin' user and do the following:
# edit the postfix config file as root sudo vi /etc/postfix/main.cf # change the line that says "relayhost = " to say # "relayhost = smtp.yourcompany.com " # save the changes then reload the postfix config sudo postfix reload
This takes care of most user's mail delivery problems but you may still have some recipients where this is not sufficient. Unfortunately, these cases are harder to diagnose and vary widely from recipient to recipient. If your mail relay requires authentication, please see our Authenticated Mail Relay FAQ.
Other Issues
Other environmental issues that are external to the JumpBox may make receiving email difficult, these include:
- DNS entry incorrect or unavailable
- Reverse DNS entry incorrect or unvailable
Testing Mail
To test whether email is getting delivered (either before or after performing the above steps) you can do the following on the command line of the JumpBox:
sendmail -t user@example.com < /etc/services
Check your spam folder to see if it was marked as spam. You can also check the mail.log file and see if the mail was accepted by the remote host, sometimes you will be told in this logfile why a message was rejected:
less /var/log/mail.log
Additional Notes
Note: By default, JumpBoxes are not configured to receive email from the internet.
Note: Some applications have Application level SMTP server settings, you may use these if you prefer, but the above method should work across all JumpBoxes.