[HDFS-12499] dfs.namenode.shared.edits.dir property is currently namenode specific key

• Type: Bug
• Status: Reopened
• Priority: Major
• Resolution: Unresolved
• Component/s: qjm
• Hadoop Flags: Incompatible change, Reviewed
• Assignee: Bharat Viswanadham
• Reporter: Bharat Viswanadham
• Created: 20/Sep/17 00:07
• Updated: 31/Oct/17 18:06

Description

HDFS + Federation cluster +QJM

dfs.shared.edits.dir property can be set as
1. dfs.shared.edits.dir.<<nameserviceId>>
2. dfs.shared.edits.dir.<<nameserviceId>> .<<namenodId>>

Configuring both ways are supported currently. Option 2 should not be supported, as for a particular nameservice quorum of journal nodes should be same.

If option 2 is supported, users can configure for a nameservice Id which is having two namenodes, they can configure different values for journal nodes. which is incorrect.

Example:
<property>
<name>dfs.nameservices</name>
<value>ns1,ns2</value>
</property>
<property>
<name>dfs.ha.namenodes.ns1</name>
<value>nn1,nn2</value>
</property>
<property>
<name>dfs.ha.namenodes.ns2</name>
<value>nn1,nn2</value>
</property>
<property>
<name>dfs.namenode.shared.edits.dir.ns1.nn1</name>
<value>qjournal://mycluster-node-1:8485;mycluster-node-2:8485;mycluster-node-3:8485/ns1</value>
</property>
<property>
<name>dfs.namenode.shared.edits.dir.ns1.nn1</name>
<value>qjournal://mycluster-node-3:8485;mycluster-node-4:8485;mycluster-node-5:8485/ns1</value>
</property>
<property>
<name>dfs.namenode.shared.edits.dir.ns2.nn1</name>
<value>qjournal://mycluster-node-1:8485;mycluster-node-2:8485;mycluster-node-3:8485/ns2</value>
</property>
<property>
<name>dfs.namenode.shared.edits.dir.ns2.nn1</name>
<value>qjournal://mycluster-node-3:8485;mycluster-node-4:8485;mycluster-node-5:8485/ns2</value>
</property>

This jira is to discuss do we need to support 2nd option way of configuring or remove it?