CentOS installation Crond: teach you step by step to set up scheduled tasks

php editor Zimo will introduce you how to install Crond in CentOS system, and teach you step by step to set up scheduled tasks. Crond is a very useful tool that can help us perform specific tasks at a specified time, such as backing up data, sending emails at scheduled times, etc. Through the guidance of this article, you will learn how to install Crond and set up scheduled tasks to make your work more efficient and automated. Follow the editor to explore together!

1. Install Crond

In the CentOS system, we can use the yum command to install the Crond service, open the terminal, and execute the following command as the root user ：

```shell

sudo yum install cronie

```

After the installation is completed, the Crond service will start automatically.

2. Configure Crond

Crond’s configuration file is located in /etc/crontab. We can use any text editor to open the file for configuration.

```bash

sudo nano /etc/crontab

In the configuration file, we need to define the execution time of the scheduled task and the command to be executed, Crond time The format is as follows:

```lua

* * * * * command to be executed

- - - - -

| | | | |

| | | | ----- day of the week (0 - 6) (Sunday=0)

| | | ------- month (1 - 12 )

| | ---------- day of the month (1 - 31)

| ---------- hour (0 - 23 )

------------- min (0 - 59)

For example, if we want to automatically back up the database at 12 o'clock every night, we can add The following configuration:

```javascript

0 0 * * * /usr/bin/mysqldump -u username -p password database_name > /path/to/backup.sql

The commands here need to use absolute paths.

3. Start and stop the Crond service

We can use the following command to start and stop the Crond service:

sudo systemctl start crond #Start the service

sudo systemctl stop crond # Stop the service

sudo systemctl status crond #View the service status

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