Icinga can be configured to send email notifications when certain events occur. However, to be able to use this feature we need to first setup email transmission from our arch linux box.
The configuration file for ssmtp is /etc/ssmtp/ssmtp.conf.
# The user that gets all the mails (UID < 1000, usually the admin)
# The mail server (where the mail is sent to), both port 465 or 587 should be acceptable
# See also http://mail.google.com/support/bin/answer.py?answer=78799
# The address where the mail appears to come from for user authentication.
# The full hostname
# Use SSL/TLS before starting negotiation
# Email 'From header's can override the default domain?