Router Mail

Since most of our routers are working reliably, sometimes for years without interruption, we tend to forget about them.

We might not be aware that it needs some software-updates or has a problem with hardware or software configuration .

Therefore we want our router to tell us, whenever something is going on that we should be aware of.

Prerequisites

A dedicated SMTP user for the router on your mail server.

We assume you already created the account router@example.net on your mail server. This account has the ability to login on the Submission server and send out mails. He does not need any access to a mailbox (IMAP etc.).

Required Software

  • ssmtp - A secure, effective and simple way of getting mail off a system to your mail hub.

To install this:

router$ opkg install ssmtp

Configuration

The configuration file is located at /etc/ssmtp/ssmtp.conf:

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     #
     # /etc/ssmtp.conf -- a config file for sSMTP sendmail.
     #

     # The person who gets all mail for userids < 1000
     # Make this empty to disable rewriting.
     root=hostmaster@example.net

     # The place where the mail goes. The actual machine name is required
     # no MX records are consulted. Commonly mailhosts are named mail.domain.com
     # The example will fit if you are in domain.com and your mailhub is so named.
     mailhub=mail.example.net:587

     # Where will the mail seem to come from?
     rewriteDomain=router.example.net

     # The full hostname
     hostname=router.example.net

     # Set this to never rewrite the "From:" line (unless not given) and to
     # use that address in the "from line" of the envelope.
     FromLineOverride=YES

     # Use SSL/TLS to send secure messages to server.
     UseTLS=YES
     UseSTARTTLS=Yes

     AuthUser=router@example.net
     AuthPass=********

     # Get enhanced (*really* enhanced) debugging information in the logs
     # If you want to have debugging of the config file parsing, move this option
     # to the top of the config file and uncomment
     #Debug=YES

Protect the configuration, since it contains account details:

router$ chown root:mail /etc/ssmtp/ssmtp.conf
router$ chmod 640 /etc/ssmtp/ssmtp.conf

Testing

To send a test mail from the router to you:

router$ ssmtp -v -F 'OpenWRT Router' -f router@example.net "Testing Router Mail Setup" user@example.net