creating tar file naming by current date backup never run

cron, linux, tar

Solution

Character `%` has a special meaning in the crontab file. It denotes a newline. Escape the `%` characters and the command should work as expected.

So instead of:

0 0 * * * tar czf /var/backups/file_$(date +%Y-%m-%d).tar.gz  /home/files

Use:

0 0 * * * tar czf /var/backups/file_$(date +\%Y-\%m-\%d).tar.gz  /home/files

Most modern cron daemons will not pass the `\` on to the shell. In case that happens, you might need to put the backup command in a separate script and then call it from crontab (that way cron daemon doesn't interpret `%` characters).

So stick the following into `/usr/local/cronscipts/my-backup-script`:

#!/bin/sh

tar czf /var/backups/file_$(date +%Y-%m-%d).tar.gz  /home/files

And then modify your cronjob to call that script:

0 0 * * * /usr/local/cronscripts/my-backup-script.

Filenames and paths here are examples only, of course. Use what suits you best and remember to give the script right permissions ie. 0700 at least.

Problem

Original source