How to monitor Symfony and Apache logs with M/Monit

So you have developed and deployed a fresh new project and you want to be alerted in case an error happens.

Here’s how you do it using the M/Monit tool.

It can be installed on an Ubuntu machine using the following command:

sudo apt-get install monit

Now edit the /etc/monit/monitrc configuration file and add the following:

set mailserver smtp.sendgrid.net port 587
  username "USERNAME" password "PASSWORD"

set alert YOUR_EMAIL@HOST.COM not on { instance, action }

set httpd port 2812 and
    use address localhost  # only accept connection from localhost
    allow localhost        # allow localhost to connect to the server and
    allow admin:monit      # require user 'admin' with password 'monit'

check file error.log with path /var/log/apache2/error.log
      if match "error" then alert

check file prod.log with path /var/www/sfproject/app/logs/prod.log
      if match "request.CRITICAL" then alert

First we need to tell M/Monit what mail server to use (we used Sendgrid but you can use whatever you want), then to specify the email address which will receive the alerts. We also have to allow connections from localhost so the status command below can be executed.

The actual monitoring is set up in the last two blocks of code, one for the apache error log and the next for the Symfony production logs. Anytime the specified string will appear in the logs, an alert email will be sent to the address we defined above.

To enable the changes, reload configuration:

monit reload

You can now check the status with the command:

monit status

It’s that simple!