Command blocks

Table of contents

Blocks that run commands, now or on a schedule.

Cron Job

Adds a line to a user’s crontab, and reloads cron when it changes.

Generates: a methods promise.

Setting	Required	Description
Command	Yes	Start with an absolute path. Runs with cron’s environment, not the agent’s. The job runs every day of the month and week, at the hours and minutes set below; Windows hosts skip it.
Run as	Yes	Default: `root`.
Hours	Yes	Cron hour field: * for every hour, 3 or 0,12 or /6. Default: ``.
Minutes	Yes	Cron minute field: 0, 15,45 or */10. Default: `0`.

The policy it generates, for example:

# Back up nightly
methods:
  "cron job for root"
    usebundle => default:cronjob(
      "/usr/local/bin/backup.sh", "root", "3", "30"
    );

Runs a command via the shell.

Generates: a commands promise.

Setting	Required	Description
Command	Yes	Start with an absolute path (/usr/bin/…). $(name) is a CFEngine variable, so write a shell $( ) as $(const.dollar)( ).
How often	No	A command runs every time the agent does (every 5 minutes by default) unless limited here. One of: Every agent run, At most once an hour, At most once a day, At most once a week, or Other… and Minutes between runs, at least 1. Default: At most once a day.

The policy it generates, for example:

# Update CA certificates
commands:
  "/usr/sbin/update-ca-certificates"
    contain => default:in_shell,
    action => default:if_elapsed("1440");