[HDFS-1850] DN should transmit absolute failed volume count rather than increments to the NN

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.22.0
• Component/s: datanode, namenode
• Hadoop Flags: Reviewed
• Assignee: Eli Collins
• Reporter: Eli Collins
• Created: 20/Apr/11 01:37
• Updated: 12/Dec/11 06:19
• Resolved: 03/May/11 01:34

Description

The API added in HDFS-811 for the DN to report volume failures to the NN is "inc(DN)". However the given sequence of events will result in the NN forgetting about reported failed volumes:

1. DN loses a volume and reports it
2. NN restarts
3. DN re-registers to the new NN

A more robust interface would be to have the DN report the total number of volume failures to the NN each heart beat (the same way other volume state is transmitted).