[HDFS-5794] Fix the inconsistency of layout version number of ADD_DATANODE_AND_STORAGE_UUIDS between trunk and branch-2

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.3.0, 3.0.0-alpha1
• Fix Version/s: 3.0.0-alpha1
• Component/s: namenode
• Hadoop Flags: Reviewed
• Assignee: Jing Zhao Assign to me
• Reporter: Jing Zhao
• Created: 16/Jan/14 23:07
• Updated: 12/May/16 18:18
• Resolved: 17/Jan/14 18:31

Description

Currently in trunk, we have the layout version:

EDITLOG_ADD_BLOCK(-48, ...),
CACHING(-49, ...),
ADD_DATANODE_AND_STORAGE_UUIDS(-50, ...);

And in branch-2, we have:

EDITLOG_SUPPORT_RETRYCACHE(-47, ...),
ADD_DATANODE_AND_STORAGE_UUIDS(-49, -47, ...);

We plan to backport HDFS-5704 and HDFS-5777 to branch-2, thus EDITLOG_ADD_BLOCK will also take -48 in branch-2. However, we cannot change ADD_DATANODE_AND_STORAGE_UUIDS to -50 in branch-2. Otherwise fsimages written by trunk and branch-2 have the same layout -50 but branch-2 cannot read the -50 fsimage if it is written by trunk.