[HADOOP-1914] HDFS should have a NamenodeProtocol to allow secondary namenodes and rebalancing processes to communicate with a primary namenode

• Type: New Feature
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.14.1
• Fix Version/s: 0.15.0
• Assignee: Hairong Kuang
• Reporter: Hairong Kuang
• Created: 18/Sep/07 00:03
• Updated: 02/May/13 02:29
• Resolved: 02/Oct/07 18:43

Description

For the security purpose, it is nice to have a NamenodeProtocol to allow secondary namenodes and rebalacing processes to communicate with a primary namenode. In the first version the NamenodeProtocol is going to support one RPC:
BlockLocations[] getBlocks(DatanodeID datanode, long size);
This RPC allows a rebalancing process to fetch a partial blocks map from a namenode. It returns a list of blocks on the given datanode and its locations, whose total size is the given size.

Issue Links

• is depended upon by: HADOOP-1652 Rebalance data blocks when new data nodes added or data nodes become full