0 0/5 * * * * Cron Expression

3 min read Jul 03, 2024

**Cron Expression: 0 0/5 * * *

Introduction

Cron expressions are used to schedule jobs in Unix-like operating systems. They consist of five or six fields that define when a command should be executed. In this article, we will break down the cron expression 0 0/5 * * * and explain what each part means.

The Fields

A cron expression consists of five fields, separated by spaces. The fields are:

Minute (0-59)
Hour (0-23)
Day of the month (1-31)
Month (1-12)
Day of the week (0-6), where 0 = Sunday

The Expression: 0 0/5 * * *

Let's break down the expression 0 0/5 * * *:

Minute: 0 means the command will be executed at the beginning of the minute.
Hour: 0/5 means the command will be executed every 5 hours, starting from 0 (midnight). The / denotes a step value, which means the command will be executed every 5 hours, rather than at a specific hour.
Day of the month: * is a wildcard, which means the command can be executed on any day of the month.
Month: * is a wildcard, which means the command can be executed in any month.
Day of the week: * is a wildcard, which means the command can be executed on any day of the week.

What This Expression Means

The cron expression 0 0/5 * * * will execute a command every 5 hours, starting from midnight. This means the command will be executed at the following times:

00:00 (midnight)
05:00
10:00
15:00
20:00

And so on.

Conclusion

In conclusion, the cron expression 0 0/5 * * * is a powerful way to schedule a command to be executed every 5 hours, starting from midnight. Understanding how to read and write cron expressions is essential for automating tasks in Unix-like operating systems.