Cron Job Shell Scripts Failing

A common request in Linux forums is shell scripts working as expected from the command line yet failing in cron jobs.

Not well understood is cron jobs do not inherit a full environment. The solution is straightforward.

Use full paths for all commands.
Explicitly declare the PATH variable in the script for commands not located in the standard environment search path
Explicitly declare environment variables, such as the DISPLAY variable.
Ensure the correct environment exists. For example, running GUI apps or commands requires X running.

Posted: October 27, 2020 Category: Usability Tagged: General