[HDFS-3853] Port MiniDFSCluster enableManagedDfsDirsRedundancy option to branch-2

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.0.2-alpha
• Fix Version/s: 0.23.2, 2.0.2-alpha
• Component/s: namenode
• Hadoop Flags: Reviewed
• Assignee: Colin McCabe
• Reporter: Colin McCabe
• Created: 24/Aug/12 23:32
• Updated: 11/Oct/12 17:46
• Resolved: 27/Aug/12 00:46

Description

MiniDFSCluster's enabledManagedDfsDirsRedunancy flag should be ported to branch-2. Certain tests rely on it to get full coverage-- for example, TestNameNodeRecovery and TestFSEditLogLoader.

Just to give an example, if we're using redundant edit log directories, a test like this may succeed for the wrong reasons:
1. screw up edit log directory
2. run recovery
3. test that we can start NN

With redundant edit log directories and edit log failover, step 1 is a no-op because we can just fail over to the other directory. So we're not really testing what we need to test. This was supposed to be ported over to branch-2 from trunk with the other stuff from HDFS-3049, but was not.

Issue Links

• blocks: HDFS-3731 2.0 release upgrade must handle blocks being written from 1.0
• relates to: HDFS-3049 During the normal loading NN startup process, fall back on a different EditLog if we see one that is corrupt