CentOS 7, a popular Linux distribution, is reaching its end of life on June 30, 2024. This means that it will no longer receive security updates or support, making it vulnerable to security risks.CentOS 7, a popular Linux distribution, is reaching its end of life on June 30, 2024. This means that it will no longer receive security updates or support, making it vulnerable to security risks. Enterprises relying on CentOS 7 should start planning their migration to an alternative distribution immediately. Several options are available, incluindo AlmaLinux, RHEL, Rocky Linux, and SUSE Linux Enterprise Server (SLES). To prepare for the migration, organizations should identify their CentOS 7 deployments, back up data, and select a replacement distribution. Tools like Lansweeper can help detect CentOS deployments and ensure a smooth migration. Additional options to consider during the migration include consolidating distributions and exploring cloud hosting. Tools like Convert2RHEL, Leap, and Elevate can assist with the migration process. It’s important to note that a clean installation can be beneficial to avoid potential issues caused by old configurations or unnecessary software. By planning and taking action promptly, organizations can ensure a smooth transition to a supported Linux distribution and maintain the security and stability of their systems.
CentOS 7 will reach end of life on June 30, 2024. This creates complications for the many organizations that still rely on CentOS deployments, making it critical to replace these systems immediately.
The EOL date represents the end of maintenance, which means that no further security or functional updates will be available and no further developments will take place. Enterprises should get installations right into their update cycle to stay on top of feature and security improvements.
CentOS EOL explained
The CentOS Linux distribution, a nearly identical alternative to RHEL, was a way to run RHEL systems without the added weight of subscriptions and other licensing challenges that the enterprise-oriented distribution brought with it.
While RHEL brought many benefits, including support, CentOS served as an alternative to developer systems, test servers, and various other places in the enterprise where simple but powerful deployments were needed.
In December 2020, Red Hat announced the end of CentOS Linux 7. The reasons for termination include:
- CentOS took advantage of RHEL’s sales opportunities by being a free but powerful alternative.
- Red Hat had the opportunity to move CentOS from a downstream version to an upstream development platform.
- Red Hat teams and customers were confused about the placement of CentOS in the sales and support model.
A recent article from Lansweeper indicated that about 26% of the Linux systems on which it had data were running CentOS. That statistic put it ahead of the ever-popular Ubuntu Linux distribution and RHEL among machines. It is impossible to know how many installations exist worldwide.
Will CentOS still run Linux 7 after its EOL?
The EOL (end of maintenance) concept does not mean that CentOS Linux is simply disabled or can no longer be used. It means that the vendor will no longer offer new features, fix security holes, and update performance options. That is not a significant problem in the short term, but it is a serious problem in the long term. Today’s security threats are reason enough to be concerned about a vendor that no longer provides patches. Performance and other implications are also a cause for concern.
CentOS 7 users can still use their systems after the EOL date, but that is not recommended. However, some users may have old applications that they cannot port to another distribution.
What about CentOS Stream?
CentOS Stream is an upstream version of RHEL, testing new features that may make their way to later RHEL versions.
The older CentOS Linux was a downstream version of RHEL and Fedora, meaning it had to wait for new features until they were integrated into the other distributions. CentOS Linux also followed RHEL’s predictable release cycle, which is important and useful for enterprises. CentOS Stream adopts a rolling release cycle to reflect its more agile and testing-oriented goal. CentOS Stream also allows direct community contributions, while CentOS Linux had no contribution scheme. The following is the status for different CentOS Stream versions:
- CentOS Stream 8 end of builds. As the upstream version of RHEL 8, CentOS Stream 8 has reached its natural conclusion. Users should consider migrating to CentOS Stream 9.
- CentOS stream 9. This is the current CentOS Stream version that serves as the upstream distribution for RHEL 9.
CentOS Stream may be a viable option for some enterprise deployments. However, Red Hat has moved CentOS Stream to an upstream RHEL version with a rolling release schedule of more experimental features, making it a less predictable choice. Now that CentOS Linux is no longer patched and CentOS Stream is a less viable alternative, companies must develop a plan to replace those systems.
CentOS Alternatives
There are numerous distributions available as replacement options for CentOS Linux. The four distributions most similar to CentOS 7 are AlmaLinux, RHEL, Rocky Linux, and SUSE Linux Enterprise Server (SLES).
SLES uses the Zypper package manager, while AlmaLinux, RHEL and Rocky Linux all use the same package managers — RPM Package Manager and Yellowdog Updater Modified/Dandified YUM — for software maintenance. They also maintain similar file, feature, and service functionality, providing comfort and familiarity. Organizations should explore these choices now to have an alternative for when CentOS 7 is no longer beneficial to the business.
Many distributions are essentially similar. The end of CentOS gives your company the opportunity to consolidate systems and focus on maintaining fewer distributions.
Immediate actions
Many distributions are essentially similar. The end of CentOS allows a company to consolidate systems and focus on maintaining fewer distributions.
Start by identifying the CentOS 7 deployments in the environment. Then select a replacement distribution, paying particular attention to AlmaLinux, Rocky Linux, RHEL, and SLES. Consider other distributions that need replacing and use virtualization effectively where possible.
Once you have selected an alternative distribution for CentOS, follow these next steps:
- Identify all CentOS installations.
- Identify all applications you want to migrate.
- Back up all user, application and system data.
- Deploy and update the new distribution.
- Install all applications on the new deployments.
- Restore data, including configurations and settings.
- Test the migrated systems for full functionality.
This lengthy process can be shortened using tools like Lansweeper, which offers a new report to help detect CentOS deployments in the environment and assure the user that they have been migrated to a supported platform.
Additional options
During this migration phase from CentOS, there are some additional options available. Take a moment to consider whether additional streamlining will benefit the environment.
Other potential migration actions include:
- Bare-metal or virtualized deployments. Eliminate physical systems and migrate their services to VMs.
- On-premises or cloud deployments. Consider whether some services or systems could benefit from cloud hosting instead of maintaining them on-premises.
- Consolidate distributions. What other distributions does the organization support, and what challenges exist in maintaining a wide variety of Linux distributions? It may be useful to migrate other odd or one-off Linux installations to a chosen CentOS Linux replacement to achieve greater consistency and easier maintenance.
Migration tools
Several tools exist to assist with migrations. With the end of CentOS 7 just around the corner, tools like these are critical for a timely migration:
- Convert2RHEL. A Red Hat tool for direct conversion from CentOS 7 to RHEL 7 with minimal disruptions.
- Leap. A Red Hat tool to migrate from RHEL 7 to RHEL 8, but also works for CentOS 7 to RHEL 8 migrations – it does not support migration to “RHEL-like” distributions, such as Rocky Linux.
- Elevate. An AlmaLinux utility to migrate settings and configurations from CentOS 7 to AlmaLinux 8 or 9.
Don’t forget the value of clean installations to avoid unnecessary software, old configurations and strange settings.
Damon Garn owns Cogspinner Coaction and provides freelance IT writing and editing services. He has written multiple CompTIA study guides, including the Linux+, Cloud Essentials+, and Server+ guides, and is an extensive contributor to TechTarget Editorial and CompTIA Blogs.
