It's a question I've spent much of my adult life pondering.
sudo systemctl enable cronie.service && sudo systemctl start cronie.service./bin/sh by default, which doesn't support all Bash syntax. Notably, the &>> operator for redirecting standard output and error together won't work. You can change the default shell by declaring, e.g., SHELL=/bin/bash at the top of your crontab.SHELL, PATH, LOGNAME, and USER. This is true even if you use Bash, since Bash only reads ~/.bashrc when invoked interactively.PATH. A special case of the above: cron will run your jobs with PATH set to a limited number of locations. You can set PATH in the crontab, or spell out the full path to the executable.journalctl logs don't even tell me if the command returned an error code or not. Arch Linux's cron is much more helpful: both standard output and standard error are in sudo journalctl -u cronie.service.mycmd 2>&1 > cron.log seems logical, but it doesn't work: the right order is mycmd > cron.log 2>&1. (To be fair, this one isn't cron's fault.)crontab(5): "A '%' character in the command, unless escaped with a backslash (\), will be changed into newline characters, and all data after the first % will be sent to the command as standard input." This is true even if the percent sign is in a quoted string!