[HDFS-1125] Removing a datanode (failed or decommissioned) should not require a namenode restart

• Type: Improvement
• Status: Resolved
• Priority: Blocker
• Resolution: Duplicate
• Affects Version/s: 0.20.2
• Component/s: namenode
• Assignee: Unassigned
• Reporter: Alex Loddengaard
• Created: 03/May/10 19:16
• Updated: 03/Jul/12 13:10
• Resolved: 03/Jul/12 12:44

Description

I've heard of several Hadoop users using dfsadmin -report to monitor the number of dead nodes, and alert if that number is not 0. This mechanism tends to work pretty well, except when a node is decommissioned or fails, because then the namenode requires a restart for said node to be entirely removed from HDFS. More details here:

http://markmail.org/search/?q=decommissioned%20node%20showing%20up%20ad%20dead%20node%20in%20web%20based%09interface%20to%20namenode#query:decommissioned%20node%20showing%20up%20ad%20dead%20node%20in%20web%20based%09interface%20to%20namenode+page:1+mid:7gwqwdkobgfuszb4+state:results

Removal from the exclude file and a refresh should get rid of the dead node.

Issue Links

• is related to: HDFS-1290 decommissioned nodes report not consistent / clear
• relates to: HDFS-1290 decommissioned nodes report not consistent / clear