Overview of Migrating to AlmaLinux
This chapter provides complete guides for migrating to AlmaLinux from various operating systems. AlmaLinux is 1:1 binary compatible with RHEL, making it an ideal free replacement for systems such as CentOS.
Read before migrating
- Always make a complete backup of system configuration and business data, and prepare a rollback plan (snapshot / failover).
- When working remotely, keep one connected session open to avoid locking yourself out during network / SSH / firewall changes.
- Before migrating a production environment, rehearse the entire process in a test environment first.
Choosing a Migration Method
| Method | Use Case | Notes |
|---|---|---|
| ELevate in-place upgrade | Cross-major-version upgrades for the EL family (CentOS/RHEL/Oracle/Rocky) | Based on leapp; supports el7→8, el8→9, el9→10. See the official ELevate documentation |
| Fresh install + data migration | Too large a gap, or a desire for a clean system (e.g. CentOS 7, cross-distribution) | The safest, and easy to roll back |
| Dual-machine migration | Critical workloads requiring smooth cutover | Old and new run in parallel, shifting traffic gradually |
Migration Guides
- CentOS 7 → AlmaLinux 10: a large gap; a fresh install + data migration is recommended
- CentOS Stream → AlmaLinux 10: an ELevate in-place upgrade is available
- RHEL → AlmaLinux 10: free of subscription fees while keeping technical compatibility
- Oracle Linux → AlmaLinux 10: watch out for the UEK kernel and Oracle components
- Debian → AlmaLinux 10: cross-distribution; the environment needs to be rebuilt
- Windows Server → AlmaLinux 10: cross-platform, focused on replacing the application stack
Tip
CentOS Linux 7 (2024-06-30) and CentOS Linux 8 (2021-12-31) are both EOL and no longer receive security updates; systems still running them should be migrated as soon as possible. After migration, it is advisable to read the Security Hardening Guide.
If you are evaluating migration paths across multiple distributions such as CentOS, Rocky Linux, and Oracle Linux, RunEntLinux provides migration and operations field documentation covering the entire enterprise Linux family, which can serve as supplementary reference.
