The announcement and availability of CentOS Stream has the potential to improve RDO’s feedback loop to Red Hat Enterprise Linux (RHEL) development and smooth out transitions between minor and major releases. Let’s take a look at where RDO interacts with the CentOS Project and how this may improve our work and releases.
RDO and the CentOS Project
Because of tight coupling with the operating system, RDO project joined the CentOS SIGs initiative from the beginning. CentOS SIGs are smaller groups within the CentOS Project community focusing on a specific area or software type. RDO was a founding member of the CentOS Cloud SIG that is focusing on cloud infrastructure software stacks and is using the CentOS Community BuildSystem (CBS) to build final releases.
In addition to Cloud SIG OpenStack repositories, during release development RDO Trunk repositories provide packages for new commits in OpenStack projects soon after they are merged upstream. After commits are merged a new package is created and a YUM repository is published in RDO Trunk server, including this new package build and the latest builds for the rest of packages in the same release.This enables packagers to identify packaging issues almost immediately after they are introduced, shortening the feedback loop to the upstream projects.
How CentOS Stream can help
A stable base operating system, on which continuously changing upstream code is built and tested, is a prerequisite. While CentOS Linux did come close to this ideal, there were still occasional changes in the base OS that were breaking OpenStack CI, especially after a minor CentOS Linux release where it was not possible to catch those changes before they were published.
The availability of rolling-release CentOS Stream, announced alongside CentOS Linux 8, will help enable our developers to provide earlier feedback to the CentOS and RHEL development cycles before breaking changes are published. When breaking changes are necessary, it will help us adjust for them ahead of time.
A major release like CentOS Linux 8 is even more of a challenge, RDO has managed to transition from EL6 to EL7 during the OpenStack Icehouse cycle by doing two distributions in parallel – five years ago, with a much smaller package set than it is now.
For the current OpenStack Train release in development, the RDO project started preparing for the Python 3 transition using Fedora 28, which helped to get this huge migration effort going, at the same time it was only a rough approximation for RHEL 8/CentOS Linux 8 and required complete re-testing on RHEL.
Since CentOS Linux 8 is released very closely to the OpenStack Train release, the RDO project will be able to provide RDO Train initially only on EL7 platform and will add CentOS Linux 8 support in RDO Train soon after.
For the future releases, the RDO project is looking forward to be able to start testing and developing against CentOS Stream updates as they are developed, to provide feedback, and help stabilize the base OS platform for everyone!
About The RDO Project
The RDO project is providing a freely-available, community-supported distribution of OpenStack that runs on Red Hat Enterprise Linux (RHEL) and its derivatives, such as CentOS Linux. RDO also makes the latest OpenStack code available for continuous testing while the release is under development.
In addition to providing a set of software packages, RDO is also a community of users of cloud computing platforms on Red Hat-based operating systems where you can go to get help and compare notes on running OpenStack.