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Brahma Reddy Battula commented on HDFS-8647: -------------------------------------------- {quote}Ideally HDFS should support auto replication for the case where # of rack changes from 1 to 2 after NN's restart. But that requires more work and it is an existing issue. You can open a new jira for that.{quote} [~mingma] Raised seperate jira to handle this..(HDFS-9127)..will update patch by keeping current behavior as it is. > Abstract BlockManager's rack policy into BlockPlacementPolicy > ------------------------------------------------------------- > > Key: HDFS-8647 > URL: https://issues.apache.org/jira/browse/HDFS-8647 > Project: Hadoop HDFS > Issue Type: Improvement > Reporter: Ming Ma > Assignee: Brahma Reddy Battula > Attachments: HDFS-8647-001.patch, HDFS-8647-002.patch, > HDFS-8647-003.patch > > > Sometimes we want to have namenode use alternative block placement policy > such as upgrade domains in HDFS-7541. > BlockManager has built-in assumption about rack policy in functions such as > useDelHint, blockHasEnoughRacks. That means when we have new block placement > policy, we need to modify BlockManager to account for the new policy. Ideally > BlockManager should ask BlockPlacementPolicy object instead. That will allow > us to provide new BlockPlacementPolicy without changing BlockManager. -- This message was sent by Atlassian JIRA (v6.3.4#6332)