Solved: Crontab bad minute error

Better Stack Team
Updated on January 9, 2023

Cause of the error

Cron reads every line of the crontab. If the line is not a comment or an environmental variable, cron expects a correct and valid minute expression of the cronjob. If there is an invalid minute expression (e.g. a typo), cron will throw a Bad minute error.

Solution

Troubleshooting

  1. The error message includes a specific line number. Look at the line and look for syntax errors and typos.
 
   "/tmp/crontab.gLfS38":4: bad minute
   #error on line 4
  1. Check for unexpected line breaks. Check the example of an unexpected line break bellow:
 
   0 0 * * *
   /command/to/execute

Make sure there is one cronjob per line. One cronjob should not be defined on multiple lines.

  1. Make sure all comments start with # and are on separate lines.
  2. Check if time schedule corresponds with the syntax rules as shown bellow

Crontab syntax

Crontabs have simple, but strict syntax rules. Every crontab file has to:

  • Start whit a correct cron schedule (can be an environmental variable) or comment on every line
  • Contain a username for each cron job
  • Contain valid and executable shell expression
  • End with a newline
 
# Example of job definition:
# .---------------- minute (0 - 59)
# |  .------------- hour (0 - 23)
# |  |  .---------- day of month (1 - 31)
# |  |  |  .------- month (1 - 12) OR jan,feb,mar,apr ...
# |  |  |  |  .---- day of week (0 - 6) (Sunday=0 or 7) OR sun,mon,tue,wed,thu,fri,sat
# |  |  |  |  | .---- username
# |  |  |  |  | |
# *  *  *  *  * user  command to be executed
*  *  *  *  *  root   echo 'Hello world!'

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