Downgrading from CloudLinux 9 to CloudLinux 8 is not a straightforward process and is generally not recommended due to potential compatibility issues and complexities involved in reverting major system changes.

Here are some reasons why downgrading can be problematic:

1. Package Compatibility: CloudLinux 9 likely includes updated packages, libraries, and software versions that may not be compatible with CloudLinux 8. Downgrading could lead to conflicts and instability.

2. Kernel Differences: CloudLinux 9 might have a different kernel compared to CloudLinux 8. Reverting to an older kernel could lead to hardware compatibility issues.

3. Configuration Changes: CloudLinux 9 may have introduced configuration changes or new features that are not present in CloudLinux 8. Downgrading could result in configuration conflicts or missing functionality.

4. Data Loss or Corruption: Performing a downgrade without proper backup and migration procedures could lead to data loss or corruption.

Given these complexities, it is generally recommended to perform a clean re-installation of CloudLinux 8 rather than attempting a downgrade. This ensures a clean and stable environment without potential compatibility issues.

If you need to retain data and configurations from your CloudLinux 9 installation, consider the following steps:

1. Backup Data: Prioritize data backup. Ensure all important files, databases, configurations, and user data are securely backed up.

2. Document Configurations: Document any custom configurations, settings, or applications you have installed on CloudLinux 9. This will be useful for reconfiguration on CloudLinux 8.

3. Prepare for Reinstallation: Set up a clean CloudLinux 8 environment on a separate server or partition.

4. Restore Data and Configurations: Once CloudLinux 8 is installed, transfer and restore your backed-up data and configurations.

5. Reconfigure Services: Reconfigure services, applications, and settings based on the documentation you created in step 2.

6. Test and Verify: Thoroughly test your services and configurations to ensure everything is working as expected.

Remember, any major system changes, including downgrades or migrations, should be carefully planned and executed to minimize potential disruptions and data loss. If you are uncertain about the process, consider seeking assistance from experienced system administrators or CloudLinux support.