Check Current CentOS Release:

/etc/redhat-release is the file having the current version of CentOS running on your system. Use following command to check the current release.

# cat /etc/redhat-release

CentOS release 6.7 (Final)

Upgrade CentOS to Latest Release:

Following are the steps to help you to upgrade CentOS to the latest release. Before upgrading centos make sure you have taken backup of all your data to a remote location.

For you reference, first..below the items, you may need to first. It may be there is more database. So take a backup of all your data first.

Step 1: Backup Important Data

Below is few suggested items to take backup.

  • Backup all databases ( MySQL, PostgreSQL, etc.. )
  • Backup all configuration files ( Apache, PHP, MySQL, DNS and Other services )
  • Backup all websites data running in webserver
  • Backup other service if any running on system

Step 2: Upgrade CentOS

Use yum upgrade command to upgrade your current running system.

# yum clean all
# yum update

After successful completion of above command just reboot your system.

# reboot

Step 3: Verify Upgrade

Finally verify that your system has been upgraded successfully. To confirm it check the /etc/redhat-release file content.

# cat /etc/redhat-release
CentOS release 6.8 (Final)