[MAPREDUCE-1837] Raid should store the metadata in HDFS

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 0.22.0
• Component/s: contrib/raid
• Assignee: Scott Chen
• Reporter: Scott Chen
• Created: 02/Jun/10 20:08
• Updated: 01/Aug/17 17:12
• Resolved: 01/Aug/17 17:12

Description

Currently if you change the stripe length in the raid policy. The existing raided files cannot be recovered.
Also in the future if we want to upgrade to a better erasure code such as Reed-Solomon or LDPC and change the policy for that.
The same problem will happen. We can avoid this problem if we store the information in a metadata file.

Issue Links

• is related to: HDFS-503 Implement erasure coding as a layer on HDFS