[HDFS-3164] Move DatanodeInfo#hostName to DatanodeID

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.0.0-alpha
• Component/s: datanode
• Hadoop Flags: Incompatible change, Reviewed
• Release Note: This change modifies DatanodeID, which is part of the client to server protocol, therefore clients must be upgraded with servers.
• Assignee: Eli Collins
• Reporter: Eli Collins
• Created: 30/Mar/12 00:25
• Updated: 28/Sep/15 20:58
• Resolved: 31/Mar/12 20:02

Description

Like HDFS-3138 (the ipcPort) the hostName field in DatanodeInfo is not ephemeral and should be in DatanodeID. This also allows us to fixup the issue where the DatanodeID#name field is overloaded (the DN sets it to a hostname, then the NN clobbers it with an IP, and then the DN clobbers it's hostname field with this IP). If the DN can specify both a "name" and "hostname" in the DatanodeID then this code becomes simpler.

Issue Links

• is related to: HDFS-3138 Move DatanodeInfo#ipcPort to DatanodeID
• relates to: HDFS-3171 The DatanodeID "name" field is overloaded