gerlowskija opened a new pull request, #5211: URL: https://github.com/apache/solr/pull/5211
https://issues.apache.org/jira/browse/SOLR-18569 # Description Solr has long had code in ZkController to check whether the ephemeral `/live_node` entry from a previous process is still around, and wait for ZK to deleted it before proceeding. But `/live_node` entries aren't the only ephemeral nodes that Solr expects to create on startup and that can linger after process exit. The `/node_roles/` tree also contains ephemeral nodes. Currently, if any of these exist at startup-time, Solr will hit a NodeExists exception from ZK and fail to start up. # Solution This commit changes ZkController's init code so that it now waits for these nodes as well. In practice, this prevents Solr from potentially stalling on start up because of an unexpected or unhandled `NodeExists` exception. # Tests New test cases in ZkControllerTest to test how Solr handles these nodes existing when a new Solr node starts up. These tests aren't totally ideal as they involve a sleep or two: open to suggestions if anyone has ideas how to eliminate this. # Checklist Please review the following and check all that apply: - [x] I have reviewed the guidelines for [How to Contribute](https://github.com/apache/solr/blob/main/CONTRIBUTING.md) and my code conforms to the standards described there to the best of my ability. - [x] I have created a Jira issue and added the issue ID to my pull request title. - [x] I have given Solr maintainers [access](https://help.github.com/en/articles/allowing-changes-to-a-pull-request-branch-created-from-a-fork) to contribute to my PR branch. (optional but recommended, not available for branches on forks living under an organisation) - [x] I have developed this patch against the `main` branch. - [ ] I have run `./gradlew check`. - [x] I have added tests for my changes. - [x] I have added a [changelog entry](https://github.com/apache/solr/blob/main/dev-docs/changelog.adoc) for my change -- 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]
