[HDFS-16510] Fix EC decommission when rack is not enough

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Duplicate
• Affects Version/s: 3.3.1, 3.3.2
• Component/s: block placement, ec
• Labels: pull-request-available
• Assignee: daimin
• Reporter: daimin
• Due: 17/Mar/22
• Created: 17/Mar/22 09:07
• Updated: 22/Apr/22 08:49
• Resolved: 22/Apr/22 08:49

Description

The decommission always fail when we start decommission multiple nodes on a cluster whose racks is not enough, a cluster with 6 racks to deploy RS-6-3, for example.

We find that those decommission nodes cover at least a rack, it's actulaly like we are decommission one or more racks. And rack decommission is not well supported currently, especially for cluster whose racks is not enough already.

Issue Links

• is superceded by: HDFS-16456 EC: Decommission a rack with only on dn will fail when the rack number is equal with replication
• links to: GitHub Pull Request #4078