iskenderurs commented on PR #4038: URL: https://github.com/apache/ambari/pull/4038#issuecomment-6684742937
@AnanyaSingh2121, thank you for the original multiple-Standby NameNode wizard. We adapted your work to Ambari 3.0.0 / BIGTOP 3.3.0 and published the unified source and tests for discussion here: - [Source branch](https://github.com/iskenderurs/ambari/tree/AMBARI-26300-three-nn-unified-v1) - [Changes, attribution and validation boundaries](https://github.com/iskenderurs/ambari/blob/AMBARI-26300-three-nn-unified-v1/docs/hdfs-three-nn-community-review.md) - [Diff against the exact release-3.0.0 base](https://github.com/iskenderurs/ambari/compare/release-3.0.0...AMBARI-26300-three-nn-unified-v1) While adapting the proposal, we identified several areas worth addressing together: 1. The review controller's `onLoadConfigs` submits a desired `hdfs-site` configuration while loading the review page. Our adaptation makes review read-only, persists configuration during execution, and rechecks the reviewed configuration tag before installation and saving. 2. Using the whole `dfs.nameservices` value and reconstructing sequential `nn1..N` IDs can mis-handle multiple nameservices or custom IDs. The adaptation resolves the effective nameservice consistently with the backend, preserves existing identities/endpoints and allocates a non-colliding ID, including custom ports and IPv6 handling. 3. The inherited BIGTOP NN cardinality also needs to allow the third NN. The branch includes this metadata change and nameservice-scoped three-NN backend handling for rolling handoff, refusing an unconfirmed handoff without killing ZKFC as a fallback. 4. We revised execution ordering: configure the new NN before bootstrap, remove separate ZKFC-format and safemode/saveNamespace steps, deliver DataNode and client configurations, then start the new ZKFC last. DataNode refresh retains a compatibility alias. Fresh checks passed: **26 backend tests, 15 UI-logic tests, 3 fencing-guard tests and the Ember Web build**. The candidate was installed and smoke-tested on a test cluster where three NNs already existed. Earlier backend-v2 lab results are documented separately; they are not presented as an end-to-end run of the unified Web wizard. Full unified 2-to-3 wizard and loaded-configuration convergence still require integration acceptance. The branch credits your original PR/commit. Its four commits separate backend, adapted UI, integration lab and documentation. It is based on `release-3.0.0`, not a drop-in replacement for current `trunk`. The separate planned role-switch menu in #4257 is not included. We would be happy to split out relevant follow-up commits or adapt them to the direction you prefer for this PR. @JiaLiangC, could you also take a look and advise how best to contribute these fixes to AMBARI-26300? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
