[HBASE-10939] [89-fb] Adding a rack in HBase in online fashion

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.89-fb
• Fix Version/s: 0.89-fb
• Component/s: Region Assignment
• Assignee: Adela Maznikar
• Reporter: Adela Maznikar
• Created: 09/Apr/14 00:14
• Updated: 17/Jun/22 05:30
• Resolved: 09/Apr/14 00:29

Description

RegionPlacement -exprack to add a new rack into the region placement. So far we have a static assignment plan and 3 preferred locations for a region, such that the primary is the location which is serving all requests and hdfs locality is very high on all 3 nodes.
-exprack is moving the the third preferred location on the new rack such that it leaves the cluster in balanced state. After a few days locality is high enough and we make some of this new locations primaries such that again we have a balanced state in number of primaries per regionservers in the entire cluster.