From 209fd3f9fc65dde0446763ada5301a55a4dbf815 Mon Sep 17 00:00:00 2001
From: Todd Lipcon <todd@apache.org>
Date: Fri, 8 Jul 2011 00:16:07 +0000
Subject: [PATCH] HDFS-2111. Add tests for ensuring that the DN will start with
 a few bad data directories. Contributed by Harsh J Chouraria.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1144100 13f79535-47bb-0310-9956-ffa450edef68
---
 hdfs/CHANGES.txt                              |  3 ++
 .../TestDataNodeVolumeFailureToleration.java  | 49 ++++++++++++++++++-
 2 files changed, 51 insertions(+), 1 deletion(-)

diff --git a/hdfs/CHANGES.txt b/hdfs/CHANGES.txt
index 32ea9ec01a..6054c7a452 100644
--- a/hdfs/CHANGES.txt
+++ b/hdfs/CHANGES.txt
@@ -540,6 +540,9 @@ Trunk (unreleased changes)
     HDFS-2109. Store uMask as member variable to DFSClient.Conf.  (Bharath
     Mundlapudi via szetszwo)
 
+    HDFS-2111. Add tests for ensuring that the DN will start with a few bad
+    data directories. (Harsh J Chouraria via todd)
+
   OPTIMIZATIONS
 
     HDFS-1458. Improve checkpoint performance by avoiding unnecessary image
diff --git a/hdfs/src/test/hdfs/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailureToleration.java b/hdfs/src/test/hdfs/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailureToleration.java
index d569e2e086..d5f65c256e 100644
--- a/hdfs/src/test/hdfs/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailureToleration.java
+++ b/hdfs/src/test/hdfs/org/apache/hadoop/hdfs/server/datanode/TestDataNodeVolumeFailureToleration.java
@@ -24,7 +24,6 @@
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.FileUtil;
 import org.apache.hadoop.fs.Path;
-import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.DFSTestUtil;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.server.namenode.FSNamesystem;
@@ -93,6 +92,54 @@ public void tearDown() throws Exception {
     cluster.shutdown();
   }
 
+  /**
+   * Test the DFS_DATANODE_FAILED_VOLUMES_TOLERATED_KEY configuration
+   * option, ie the DN tolerates a failed-to-use scenario during
+   * its start-up.
+   */
+  @Test
+  public void testValidVolumesAtStartup() throws Exception {
+    assumeTrue(!System.getProperty("os.name").startsWith("Windows"));
+
+    // Make sure no DNs are running.
+    cluster.shutdownDataNodes();
+
+    // Bring up a datanode with two default data dirs, but with one bad one.
+    conf.setInt(DFSConfigKeys.DFS_DATANODE_FAILED_VOLUMES_TOLERATED_KEY, 1);
+
+    // We use subdirectories 0 and 1 in order to have only a single
+    // data dir's parent inject a failure.
+    File tld = new File(MiniDFSCluster.getBaseDirectory(), "badData");
+    File dataDir1 = new File(tld, "data1");
+    File dataDir1Actual = new File(dataDir1, "1");
+    dataDir1Actual.mkdirs();
+    // Force an IOE to occur on one of the dfs.data.dir.
+    File dataDir2 = new File(tld, "data2");
+    prepareDirToFail(dataDir2);
+    File dataDir2Actual = new File(dataDir2, "2");
+
+    // Start one DN, with manually managed DN dir
+    conf.set(DFSConfigKeys.DFS_DATANODE_DATA_DIR_KEY,
+        dataDir1Actual.getPath() + "," + dataDir2Actual.getPath());
+    cluster.startDataNodes(conf, 1, false, null, null);
+    cluster.waitActive();
+
+    try {
+      assertTrue("The DN should have started up fine.",
+          cluster.isDataNodeUp());
+      DataNode dn = cluster.getDataNodes().get(0);
+      String si = dn.getFSDataset().getStorageInfo();
+      assertTrue("The DN should have started with this directory",
+          si.contains(dataDir1Actual.getPath()));
+      assertFalse("The DN shouldn't have a bad directory.",
+          si.contains(dataDir2Actual.getPath()));
+    } finally {
+      cluster.shutdownDataNodes();
+      FileUtil.chmod(dataDir2.toString(), "755");
+    }
+
+  }
+
   /**
    * Test the DFS_DATANODE_FAILED_VOLUMES_TOLERATED_KEY configuration
    * option, ie the DN shuts itself down when the number of failures