Alexey Artamonov
cd9f4d6a27
Extends the ZooKeeper->KRaft migration hook so that N Kafka clusters sharing one namespace all reach KRaft automatically, with no manual steps. This closes the last gap in the migration: previously only one cluster per namespace could migrate in place (the broker pool must be named exactly "kafka" to adopt the existing <cluster>-kafka-N brokers, and that name is namespace-unique), so a second co-namespaced ZooKeeper cluster hit the render guard and its HelmRelease never rendered again -- stuck on ZooKeeper with no way forward once a future Strimzi drops the migration. The clusters now serialize on the "kafka" name automatically. Whichever upgrade wins the name (claimed atomically via kubectl create) migrates in place; a cluster that loses fails its hook fast and its next reconcile retries. Once a migrated cluster sees other ZooKeeper clusters still waiting, it frees the name: it stands up its own release-hashed "b-<hash>" broker pool (node IDs pinned clear of the existing broker and controller ranges), enables Cruise Control, drains every partition off the "kafka"-pool brokers with a remove-brokers KafkaRebalance, deletes the drained pool, and removes Cruise Control again. The next waiting cluster's retry adopts the freed name; the last one to migrate keeps "kafka". Everything happens inside the one namespace -- the hook's Role is namespaced and it never reads or touches another. Robustness details learned from live runs: - The drain rebalance sets skipHardGoalCheck: true. A mandatory broker evacuation must not be blocked by Cruise Control's capacity hard goals; under a small resources preset the capacity model can briefly over-estimate CPU from noisy samples and reject the proposal with CpuCapacityGoal even when real CPU is near idle. - The drain wait refreshes the proposal (strimzi.io/rebalance=refresh) on any NotReady and keeps polling, rather than treating it as terminal: a just-enabled Cruise Control is unreachable for a minute or two, and its model settles as metric windows age out. This also makes the drain resumable -- a re-run refreshes a stale rebalance instead of reading its old failure forever. - Cruise Control is enabled with explicit resources (it is a JVM and a tenant LimitRange would OOM it at 128Mi), transiently -- kafka.yaml never sets spec.cruiseControl, so Helm's server-side apply does not fight the hook patching it on and off. Every phase is idempotent so a Job killed mid-drain (the drain scales with data size and can run for hours) resumes on retry; the Job deadline and the release's helm-install-timeout are raised accordingly. Verified on a live cluster across five runs of two co-namespaced ZooKeeper Kafkas migrating to KRaft: both reach KRaft automatically, the first drains onto its b-<hash> pool and frees the name, the second adopts "kafka" in place (broker node IDs and PVCs unchanged), and each cluster's data is byte-for-byte identical before and after. helm-unittest 87/87 and hack/kafka-migration-hook.bats 14/14 (the real hook script against a stub kubectl) cover the freeing decision, the atomic name claim, the drain's refresh/skip-hard-goal handling, and the "delete the pool only after the rebalance is Ready" guard. Signed-off-by: Alexey Artamonov <aleksei.artamonov@aenix.io>
Cozystack
Cozystack is a free and open-source platform and framework for building clouds.
Cozystack is a CNCF Sandbox project that was originally built and sponsored by Ænix.
With Cozystack, you can transform a bunch of servers into an intelligent system with a simple REST API for spawning Kubernetes clusters, Database-as-a-Service, virtual machines, load balancers, HTTP caching services, and other services with ease.
Use Cozystack to build your own cloud or provide a cost-effective development environment.
Use-Cases
-
Using Cozystack to build a public cloud
You can use Cozystack as a backend for a public cloud -
Using Cozystack to build a private cloud
You can use Cozystack as a platform to build a private cloud powered by Infrastructure-as-Code approach -
Using Cozystack as a Kubernetes distribution
You can use Cozystack as a Kubernetes distribution for Bare Metal
Documentation
The documentation is located on the cozystack.io website.
Read the Getting Started section for a quick start.
If you encounter any difficulties, start with the troubleshooting guide and work your way through the process that we've outlined.
Versioning
Versioning adheres to the Semantic Versioning principles.
A full list of the available releases is available in the GitHub repository's Release section.
Contributions
Contributions are highly appreciated and very welcomed!
In case of bugs, please check if the issue has already been opened by checking the GitHub Issues section. If it isn't, you can open a new one. A detailed report will help us replicate it, assess it, and work on a fix.
You are welcome to take on the fix yourself. Commits are used to generate the changelog, and their author will be referenced in it.
If you have a concrete feature request, open an issue. For a cross-cutting or architectural change, open a design proposal in the community repo. For questions or early ideas, use GitHub Discussions. See CONTRIBUTING.md for the full routing.
Community
You are welcome to join us in #cozystack, on either CNCF Slack (get an invite) or Kubernetes Slack (get an invite), in our Telegram group, and at our community meetings. Add them to your Google Calendar or iCal for convenience.
Project documents
| Document | What it covers |
|---|---|
| Governance | How decisions are made and who makes them |
| Contributor Ladder | How to grow from contributor to maintainer |
| Maintainers | Who maintains the project |
| Code of Conduct | What we expect of each other |
| Security Policy | Reporting a vulnerability, and which releases get fixes |
| Adopters | Who runs Cozystack in production |
| Roadmap | Where the project is going |
License
Cozystack is licensed under Apache 2.0.
The code is provided as-is with no warranties.
Commercial Support
A list of companies providing commercial support for this project can be found on official site.