Here is a script to send notifications to a Slack channel when a server’s main partition size exceeds a safe threshold. It is tested on Red Hat 7 and macOS Mojave.

Requirements

  • Set up an incoming webhook for a Slack channel.
  • Install the python requests module on the server or computer on which the script will be run. Either:
    • pip install requests on macOS
    • yum install python-requests on Red Hat 7

  • Add your Slack webhook to the script:

    slack_webhook_url = 'https://hooks.slack.com/services/XXXXXXX/YYYYYYYY/ZZZZZZZZZ'

  • Set the percentage threshold for partition capacity. I set it to 80%:

    threshold = 80

  • If you need to add more partitions to the search, add them to the partitions list:

    partitions = ['/', '/data', '/boot']

  • If running on a Red Hat server, copy the script to /etc/cron.hourly or /etc/cron.daily depending on how often you want notifications. If running on macOS, you will have to create a LaunchDaemon to run the script on an hourly basis (for an example on how to do that, see the answer to this StackOverflow question).

The script