SUE has been migrating, automating, and managing Linux environments since 1997.
Choosing a Linux Distribution: The Complete Guide
For mission-critical servers, you typically choose between Red Hat Enterprise Linux, SUSE Linux Enterprise Server, Ubuntu LTS, or a free RHEL-compatible distribution such as Rocky Linux or AlmaLinux. The deciding factors are primarily: which distribution your software vendors certify, how much support you need, the cost of licenses, and what your team is already familiar with. Anyone still running CentOS 7 will no longer receive updates as of June 30, 2024, and must migrate.
Contents
The Essentials in Four Points
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Base your decision on your software. The distribution that your vendors certify is the most important factor. → Section 2
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Support or no license fees. RHEL and SLES offer vendor support; Rocky Linux and AlmaLinux are free and RHEL-compatible. → Section 3
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CentOS 7 will no longer receive updates as of June 30, 2024. Choose a migration path and combine it with automation. → Section 5
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Standardize. One primary distribution, at most one secondary, and everything set up with automation. → Section 6
1. Why the Choice Matters
2. Selection Criteria
Start by certifying your core applications. If your ERP or SAP vendor does not support a particular distribution, it’s out of the running—no matter how good it is in other respects.
Next, weigh these criteria
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Certification: Which distributions do the vendors of your core software—such as ERP, databases, SAP, and line-of-business applications—support?
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Lifetime: How long does a major version receive security updates?
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Support: Do you need 24/7 vendor support, or is community support plus a management partner sufficient?
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Costs: subscriptions per server, per virtual machine, or per CPU socket.
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Ecosystem: Is the distribution compatible with your platform, such as OpenShift, Rancher, or the public cloud?
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Knowledge: What does your team know, and what’s available on the job market?
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Compliance: Are there certified versions for your industry, such as FIPS or Common Criteria?
3. Comparison
4. What Happened to CentOS
For many years, CentOS Linux was the free version of RHEL. Red Hat discontinued this and replaced it with CentOS Stream: a version that is slightly ahead of RHEL and is therefore less suitable for stable production environments. CentOS Linux 7 reached end-of-life on June 30, 2024. Rocky Linux and AlmaLinux emerged as its successors.
5. Migration Paths from CentOS 7
Combine the migration with automation, such as Ansible. This allows you to set up new servers in a reproducible way, making the next migration much smaller. Rijk Zwaan We migrated the entire CentOS infrastructure to RHEL using this method.
Four Paths Starting with CentOS 7
6. Standardization
Every additional distribution or major release means its own patching process, its own set of requirements, and its own exceptions. The less variation there is, the simpler and more secure management becomes.
Here's how to keep the landscape manageable
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Choose one primary distribution, and at most one secondary distribution for specific cases, such as SLES for SAP.
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For each distribution, specify which major versions are allowed and when to upgrade.
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Set up all servers using automation, not manually.
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Apply patches according to a set schedule, and roll out emergency patches for critical vulnerabilities immediately.
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For hardening, use a fixed baseline, such as the CIS benchmarks.
7. How much does Linux cost?
The subscription is the most visible cost, but rarely the largest. Therefore, compare distributions based on both licenses and management, and factor in the risk of a version without updates.
Where the Costs Lie
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Licenses and subscriptions: RHEL and SLES operate on an annual subscription basis per server, virtual machine, or socket, with various support levels. Ubuntu, Rocky Linux, and AlmaLinux are free, with optional paid support.
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Management: often the largest expense. Applying patches, monitoring, securing systems, and handling incidents 24/7 all require staff.
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Risk: A version without support costs nothing in terms of licenses, but can be very expensive in the event of an incident.
8. Frequently Asked Questions About Linux
All frequently asked questionsBoth are enterprise distributions with long-term support. RHEL has the broadest certification for enterprise software and forms the basis of OpenShift. SUSE excels in SAP environments and high availability, and forms the basis of Rancher and SUSE Virtualization. Often, the decision comes down to what your software vendors support.
Both are free, RHEL-compatible successors to CentOS, with a similar lifecycle. Rocky Linux is supported by a community centered around the founder of CentOS; AlmaLinux is supported by a foundation backed by CloudLinux. For most workloads, the technical differences are minor.
Yes, and that happens often—for example, RHEL for general-purpose servers and SLES for SAP. Keep the number to a minimum and set everything up using the same automation tools.
Yes, especially for cloud-native and developer workloads, and with Ubuntu Pro for extended support. Just make sure your core software is certified for Ubuntu.
Each major release of Red Hat Enterprise Linux receives updates for ten years. After that, you can extend support by purchasing Extended Life Cycle Support (ELS).
| Version | Full support until | Maintenance (updates) until |
|---|---|---|
| RHEL 6 | expired | November 30, 2020 |
| RHEL 7 | August 6, 2019 | June 30, 2024 |
| RHEL 8 | May 31, 2024 | May 31, 2029 |
| RHEL 9 | May 31, 2027 | May 31, 2032 |
| RHEL 10 | May 31, 2030 | May 31, 2035 |
If you're still running RHEL 6 or 7 without ELS, you will no longer receive security updates. In that case, plan an upgrade or migration. As of October 2026; Red Hat provides approximate future dates.
Ansible is an open-source tool from Red Hat that captures server configurations as code. You describe in playbooks what a server should look like, and Ansible brings each server into that state. No agent runs on the servers: Ansible works via SSH. During a migration, this allows you to set up each new server identically, test the configuration in advance, and repeat the process. This also makes subsequent migrations less complex. For larger environments, there’s the commercial Red Hat Ansible Automation Platform, which includes a web interface, access control, and logging. To learn how to write an Ansible role, check out our blog post on Ansible best practices.
Broadcom will support vSphere 8 and ESXi 8 through October 11, 2027. Those who do not wish to migrate to VMware Cloud Foundation 9 after that date can choose from platforms based on Linux and KVM:
- KVM with libvirt on RHEL or SLES: the foundation of nearly all alternatives. Suitable for smaller environments where users have their own Linux expertise.
- SUSE Virtualization (formerly Harvester): virtualization on Kubernetes, managed from Rancher.
- Red Hat OpenShift Virtualization: virtual machines alongside containers on OpenShift.
- Proxmox VE: Based on Debian, with its own web interface and optional paid support. Popular among smaller teams.
Which one is right for you depends on the number of VMs, your management expertise, and whether you also want to run containers on the same platform. You can find more information on this in the Kubernetes guide.
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SUE has been migrating, automating, and managing Linux environments since 1997.
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