[HDFS-6001] In HDFS HA setup, FileSystem.getUri returns hdfs://<dfs.nameservices>

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Not A Problem
• Affects Version/s: 2.2.0
• Component/s: ha
• Assignee: Unassigned
• Reporter: Jerry He
• Created: 24/Feb/14 05:48
• Updated: 25/Feb/14 06:02
• Resolved: 25/Feb/14 06:02

Description

When hdfs is set up with HA enable, FileSystem.getUri returns hdfs://<the-value-of-dfs.nameservices>
Here dfs.nameservices is defined when HA is enabled. In documentation:

dfs.nameservices - the logical name for this new nameserviceChoose a logical name for this nameservice, for example "mycluster", and use this logical name for the value of this config option. The name you choose is arbitrary. It will be used both for configuration and as the authority component of absolute HDFS paths in the cluster.
Note: If you are also using HDFS Federation, this configuration setting should also include the list of other nameservices, HA or otherwise, as a comma-separated list.
<property>
<name>dfs.nameservices</name>
<value>mycluster</value>
</property>

This is probably ok or even intended. But a caller may further process the URI, for example, call URI.getHost(). This will return the 'mycluster', which is not a valid host anywhere.