[HDFS-5939] WebHdfs returns misleading error code and logs nothing if trying to create a file with no DNs in cluster

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.3.0
• Fix Version/s: 2.4.0
• Component/s: hdfs-client
• Hadoop Flags: Reviewed
• Assignee: Yongjun Zhang
• Reporter: Yongjun Zhang
• Created: 12/Feb/14 19:35
• Updated: 11/Feb/15 22:13
• Resolved: 25/Feb/14 18:42

Description

When trying to access hdfs via webhdfs, and when datanode is dead, user will see an exception below without any clue that it's caused by dead datanode:

$ curl -i -X PUT ".../webhdfs/v1/t1?op=CREATE&user.name=<userName>&overwrite=false"

...
{"RemoteException":{"exception":"IllegalArgumentException","javaClassName":"java.lang.IllegalArgumentException","message":"n must be positive"}}

Need to fix the report to give user hint about dead datanode.

Issue Links

• incorporates: HADOOP-6359 NetworkTopology.chooseRandom(..) throws an IllegalArgumentException