hanmz opened a new pull request, #22362: URL: https://github.com/apache/pulsar/pull/22362
### Motivation https://github.com/apache/pulsar/pull/21367 Support to migrate topics from blue to green cluster per namespace But when we enable namespace migration, there was no check if the migrate cluster existed. There will be some unusual situations here. **Minimal reproduce step:** 1.Start a single broker node and create a tenant `test-tenant` sh bin/pulsar-admin tenants create test-tenant 2.Create a new namespace and a topic. sh bin/pulsar-admin namespaces create test-tenant/test-ns sh bin/pulsar-admin topics create test-tenant/test-ns/test-topic 3.Enable namespaces migration sh bin/pulsar-admin namespaces update-migration-state --migrated test-tenant/test-ns We will see the following log:  ### Modifications 1. Check migration cluster exist when enable namespace migration. 2. Determine whether `clusterData is exists` and `isNamespaceMigrationEnabled=true` satisfied at the same time in method `getMigratedClusterUrlAsync` ### Documentation <!-- DO NOT REMOVE THIS SECTION. CHECK THE PROPER BOX ONLY. --> - [ ] `doc` <!-- Your PR contains doc changes. --> - [ ] `doc-required` <!-- Your PR changes impact docs and you will update later --> - [x] `doc-not-needed` <!-- Your PR changes do not impact docs --> - [ ] `doc-complete` <!-- Docs have been already added --> -- 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]
