Thursday, May 15, 2014

ssmtp to email cron output

Cron output in Ubuntu gets discarded. The default install of Ubuntu does not install a Mail Transport Agent (MTA), so cron cannot mail you the output.

You can install an MTA -several are easily available in the Ubuntu repositories- but configuration is not trivial. MTAs date from before the IMAP- and SMTP-based e-mail systems we use today, which makes them highly flexible and configurable...but not necessarily the easiest solution.

ssmtp is a limited-purpose MTA intended to replace the 'mail' command and send all output to an SMTP mailserver. ssmtp is provided by the 'ssmtp' package.


sudo apt-get install ssmtp

Configuration file #1: /etc/ssmtp/ssmpt.conf

This tells ssmtp how to send email to my account.
It's not the best idea to store your e-mail password in world-readable plain text. See how to protect the password properly.

# Config file for sSMTP sendmail
# The person who gets all mail for userids < 1000
# Make this empty to disable rewriting.

# The place where the mail goes. The actual machine name is required no
# MX records are consulted. Commonly mailhosts are named

# Where will the mail seem to come from?

# The full hostname

# Are users allowed to set their own From: address?
# YES - Allow the user to specify their own From: address
# NO - Use the system generated From: address

Configuration File #2: /etc/ssmtp/

This directs root mail to my account.

# sSMTP aliases
# Format:       local_account:outgoing_address:mailhub
# Example: root:your_login@your.domain:mailhub.your.domain[:port]
# where [:port] is an optional port number that defaults to 25.

And now cron output lands in my normal inbox.