The Migration Journey: Transitioning from CentOS 7 and Rocky Linux 8 to AlmaLinux 9 and Beyond
Personal note :
I would like to emphasize that this detailed account is a reflection of my personal experience and viewpoint regarding the infrastructure overhaul and hardware reconfiguration undertaken. It is not intended to denigrate or assign blame to any individual, company, or technology involved. Rather, it aims to offer insights and learnings gained through navigating a complex technical landscape. The documented processes and decisions are based on my observations and aimed solely at providing a transparent account of the journey without any intention of disparagement.
Furthermore, it's important to note that I have not received any form of compensation, financial or otherwise, for discussing any operating systems, including AlmaLinux, within this document. My insights and evaluations are driven solely by my experiences and are not influenced by external factors. This ensures that the information presented remains as impartial and objective as humanly possible, serving the purpose of providing valuable insights into the migration journey.
Executive Summary:
The migration journey from CentOS 7 to Rocky Linux 8 represents a significant testament to the strategic evolution and technological adaptability of our infrastructure. Commencing with an environment managed manually and lacking crucial Single Sign-On (SSO) integration and centralized user management, the transition was a comprehensive overhaul orchestrated with precision.
Integration of critical services such as SSSD (SSSD - System Security Services Daemon), PAM (Pluggable Authentication Modules), and KRB5 (Kerberos 5) laid the foundation for a unified authentication mechanism, seamlessly integrating with Active Directory. Enriching repository landscapes through RPMFusion-Free fortified the available package pool, enabling seamless deployments and software updates.
A meticulous development and testing phase ensured a seamless migration, transforming previously untouched CentOS 7 workstations into candidates for rigorous testing. Ansible's implementation streamlined deployment and configuration management, facilitating automated updates and installations across the network.
The successful transition to Rocky Linux 8 by December 2022, stabilized by March 2023, marked a pivotal achievement. Subsequent explorations into next-generation operating systems like AlmaLinux 9 unveiled challenges, notably with GDM versions impacting Active Directory binding. Collaborative support from the AlmaLinux community and TuxCare underscored collective resolve in addressing intricate technical challenges.
This migration journey represents more than a technical shift; it epitomizes resilience, adaptability, and collaborative problem-solving. It showcases the capacity to navigate complex technological landscapes, reflecting a strategic evolution in infrastructure management. The integration of AlmaLinux 9 into our exploration signifies our commitment to embracing cutting-edge solutions and ensuring the continued innovation and stability of our infrastructure.
Initial Infrastructure and User Management: Upon joining the team, the existing infrastructure running CentOS 7 was predominantly managed through manual configurations, lacking centralized management or orchestration. The absence of Single Sign-On (SSO) or Active Directory integration accentuated security vulnerabilities and operational inefficiencies. The decentralized user management system, reliant on manual creation and maintenance of user accounts across workstations, posed challenges in user authentication, access control, and user-specific configurations.
Integration of Key Services: SSSD, PAM, and KRB5: The foremost challenge addressed was the integration of essential services like SSSD, PAM, and KRB5. This integration revolutionized the authentication and authorization landscape, enabling a unified authentication mechanism that integrated seamlessly with Active Directory. The deployment of SSSD facilitated centralized user authentication, enabling users to log in using their Active Directory credentials. This centralization significantly enhanced security measures and streamlined user management across the infrastructure.
Implementation of Ansible for Streamlined Management: The introduction of Ansible marked a significant paradigm shift in infrastructure management. Ansible's implementation streamlined deployment and configuration management processes, facilitating seamless updates and installations across the network. Additionally, the deployment of critical services like SSSD, PAM, and KRB5 laid the foundation for a unified authentication mechanism, seamlessly integrating with Active Directory and significantly enhancing security measures and user management across our infrastructure.
Building a Solid Foundation and Expanding Repositories: To fortify the infrastructure, efforts were directed towards expanding the repository landscape. Integration of repositories such as RPMFusion-Free filled the void by providing essential packages missing from default repositories like Devel, Extra, and Epel-Release. This strategic enhancement not only enriched the available package pool but also laid the groundwork for the deployment of critical software and utilities required for diverse operational needs.
Thorough Dev and Testing Phase: The transition process necessitated a meticulous development and testing phase to ensure a seamless migration from CentOS 7 to Rocky Linux 8. Workstations running CentOS 7, which had been historically untouched due to fear of disruption, became focal points for rigorous testing. The comprehensive testing phase aimed to mitigate risks, ensuring that the migration process would not impact critical operations or workflows. This phase of validation and testing was fundamental in mitigating potential disruptions during the migration.
领英推荐
Seamless Transition to Rocky 8 and Ensuring Stability: The migration to Rocky 8, completed by December 2022 and stabilized by March 2023, marked a pivotal achievement in infrastructure transformation. The transition was more than a mere migration; it represented a substantial overhaul with an integrated approach to ensure stability, compatibility, and adaptability. The successful transition underscored the team's adaptability and resilience in embracing new technologies and architectures while ensuring minimal disruption to ongoing operations.
Exploring Next-Generation OS Options: As the infrastructure settled into Rocky Linux 8, the quest for the next-generation operating system began. Evaluation criteria encompassed advanced kernel features, ease of integration, community support, and potential benefits for the evolving infrastructure. The evaluation process spanned multiple OS options, including Rocky Linux 9, AlmaLinux 9, Oracle Linux 9, and OpenSUSE, each meticulously scrutinized for compatibility, support, and forward-looking advantages.
Among these contenders, AlmaLinux 9 emerged as the clear winner, largely due to the strength of its community. While other options like OpenSUSE and Oracle Linux boast excellent support teams, AlmaLinux's community support stood out remarkably.
However, community support was not the only factor tipping the scales in AlmaLinux's favor. Their decision to forge their own path away from RHEL (Red Hat Enterprise Linux) downstream and establish themselves as an independent Enterprise Linux (EL) operating system speaks volumes about the team's dedication to the AlmaLinux Foundation.
AlmaLinux's stability sets it apart. The meticulous testing conducted by their team ensures smooth sailing with every patch, update, or package, making the transition between versions seamless.
Furthermore, the ELevate software developed and maintained by the AlmaLinux team facilitated our migration from Rocky Linux 8 to Alma Linux 9 effortlessly. This software brings stability, security, and operational efficiency back to standard faster than ever.
In terms of security, AlmaLinux once again proved its mettle. When a security breach (CVE-2024-1086 and XZ) was discovered in a certain kernel, the AlmaLinux team promptly fixed and deployed the solution to their community, underscoring their commitment to maintaining stringent security standards.
Even more commendable is the recent initiative by the AlmaLinux team to reintroduce support for older hardware. This decision, born out of a Hackathon hosted just before CloudFest Germany 2024, benefits small businesses with aging yet viable hardware. This initiative reflects AlmaLinux's commitment to inclusivity and practicality.
While these developments were not available at the time of our initial analysis, they further solidify our confidence in AlmaLinux. The choice to embrace AlmaLinux was deliberate, and looking back, it's a decision we stand by wholeheartedly, with no inclination to explore alternative options in the future.
Challenges Faced and Resolution Efforts: During the exploration of transitioning from Rocky Linux 8 to AlmaLinux 9, we encountered challenges replicating configurations and ensuring package compatibility. Notably, a significant issue arose with GDM's version, impacting Active Directory binding. Resolution efforts demanded collaborative support from the AlmaLinux community and the TuxCare team, emphasizing the depth of community engagement and the collective resolve to address intricate technical challenges. Continuous testing and backporting strategies have been implemented to ensure that the GDM version was fixed and that the issue was properly resolved (Big thanks to the AlmaLinux 9 community who did the backport in a timely manner).
Conclusion: The migration journey from CentOS 7 and Rocky Linux 8 to AlmaLinux 9 and the subsequent explorations of next-generation operating systems reflect more than a technical transition; it signifies a strategic evolution in infrastructure management and adaptability. The integration of critical services, automation through Ansible, and meticulous testing not only ensured a seamless transition but also underscored the team's resilience and capacity to navigate complex technological landscapes. This journey serves as a testament to collaborative problem-solving, strategic planning, and adaptability, showcasing how technology transformations can be orchestrated successfully in intricate IT ecosystems.
Reference: