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Elevate your os from Centos7 To Almalinux8

Published 19 June 2024

Upgrading from CentOS 7 to AlmaLinux 8: The cPanel ELevate Guide

The cPanel ELevate Project provides a streamlined script to upgrade an existing cPanel & WHM RHEL 7-based server installation to a RHEL 8-based installation.

Common Upgrade Paths:

CentOS 7 → AlmaLinux 8
CloudLinux 7 → CloudLinux 8

While this tool is powerful, it involves significant changes to the operating system. InterServer strongly recommends performing upgrades primarily on KVM VPS systems where snapshots can be utilized for safety.

Platform Specific Recommendations

1. KVM VPS (Recommended)

This is the safest environment for the ELevate process.

Process: We will perform a snapshot and a full backup before initiating the upgrade.
Risk Mitigation: If the upgrade fails (e.g., due to custom drivers or incomplete software upgrades), we can utilize ZFS snapshots to roll the system back to CentOS 7 immediately.

2. OpenVZ / Virtuozzo 7 (Not Supported)

You cannot ELevate a Virtuozzo 7 container, the method has proven too unreliable.

Action Required: Users on OpenVZ must migrate to a KVM system.
More Info: Please refer to the Virtuozzo 7 End of Life information.

3. Dedicated / Bare Metal Servers (High Risk)

We generally do not recommend using ELevate on live dedicated servers.

The Risk: If a failure occurs, there is no “snapshot” to restore. A failure could lead to total data loss requiring a full OS reinstall and manual data restoration.
Exceptions: We will only proceed if you have a verified full remote backup of all accounts and acknowledge that a failed upgrade may require a complete server provision and manual restore.

Critical Considerations Before Upgrading

The move to RHEL 8/AlmaLinux 8 brings modern security standards that may break legacy setups.

1. PHP Version Support

Minimum Version: Native support for PHP versions older than 7.2 is dropped.
Legacy Scripts: If your sites rely on PHP 5.x, 7.0, or 7.1, they will not work after the upgrade unless you are using CloudLinux/Imunify features that specifically provide hardened PHP (and even then, compatibility is not guaranteed).

2. Security Protocols (SSL/TLS)

Old security ciphers are disabled by default in RHEL 8.

Protocols Disabled: SSLv3, TLS 1.0, and TLS 1.1.
Impact: Users on legacy operating systems (Windows XP, Windows 7) may be unable to connect to email services. These protocols have been End-of-Life since 2018.
Warning: Re-enabling these old ciphers is unsupported and may be impossible in newer cPanel versions (v132+).

3. Authentication Changes

Plain Text Auth: Clear text authentication for POP/IMAP/SMTP will be disabled. Users must use SSL/TLS settings in their email clients.

Pre-Upgrade Checklist

To ensure a smooth transition, the following states must be met before attempting the upgrade:

Update Database: MySQL must be upgraded to version 8.0 or MariaDB to 10.5+.
System Updates: All CentOS 7.9 updates must be fully applied (yum update).
Remove Software:
- Remove PHP versions below 7.2.
- Remove cPanel Calendars and Contacts plugins.
- Third-party repositories and RPMs likely need to be removed.
- Imunify360 (if used) may need to be temporarily uninstalled.
Test Email: We recommend manually disabling SSLv3/TLS 1.1 and Plain Text Auth in Exim/Dovecot now to see which users report connection issues before the actual migration.

What to Expect During the Upgrade

Downtime: The process typically takes 1 to 3 hours.
Service State: The server will be degraded or non-functional during this time. We attempt to disable services so external connections retry later rather than fail, but small windows of data loss (e.g., incoming email during the switch) are possible.
Custom Configurations: Any non-standard customizations (e.g., manually installed ImageMagick, FFmpeg, or custom kernel drivers) may be lost and will need to be re-installed manually after the upgrade.

Upgrade Path Summary

The following chart summarizes the recommended path based on your current server infrastructure.

Server Infrastructure	Upgrade Feasibility	Recommendation	Safety Measures
KVM VPS	High	Recommended	Snapshot taken prior to upgrade. Easy rollback if failure occurs.
OpenVZ / Virtuozzo 7	None	Migrate Only	Cannot ELevate. Must migrate accounts to a new KVM VPS.
Dedicated / Bare Metal	Low	Not Recommended	Requires full off-site backup. High risk of extended downtime or total reinstall.

Need assistance?
If you are unsure about your server type or have questions about legacy script compatibility, please reach out to InterServer support before requesting an upgrade.