From d2b5531b0f034cbcde4f6dfaaba463b347fbc60b Mon Sep 17 00:00:00 2001
From: Eli Collins <eli@apache.org>
Date: Fri, 3 Feb 2012 03:10:57 +0000
Subject: [PATCH] HDFS-2769. HA: When HA is enabled with a shared edits dir,
 that dir should be marked required. Contributed by Aaron T. Myers.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/HDFS-1623@1239988 13f79535-47bb-0310-9956-ffa450edef68
---
 .../hadoop-hdfs/CHANGES.HDFS-1623.txt         |  3 ++
 .../hdfs/server/namenode/FSNamesystem.java    | 14 +++++++--
 .../namenode/ha/TestFailureOfSharedDir.java   | 29 +++++++++++++++++--
 3 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.HDFS-1623.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.HDFS-1623.txt
index e95eb5c94e6..9e24b2071fd 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.HDFS-1623.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.HDFS-1623.txt
@@ -155,3 +155,6 @@ HDFS-2859. LOCAL_ADDRESS_MATCHER.match has NPE when called from DFSUtil.getSuffi
 HDFS-2861. checkpointing should verify that the dfs.http.address has been configured to a non-loopback for peer NN (todd)
 
 HDFS-2860. TestDFSRollback#testRollback is failing. (atm)
+
+HDFS-2769. HA: When HA is enabled with a shared edits dir, that dir should be
+marked required. (atm via eli)
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java
index b49005ff144..7754a9085b2 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/FSNamesystem.java
@@ -632,9 +632,19 @@ void checkOperation(OperationCategory op) throws StandbyException {
   public static Collection<URI> getNamespaceDirs(Configuration conf) {
     return getStorageDirs(conf, DFS_NAMENODE_NAME_DIR_KEY);
   }
-  
+
+  /**
+   * Get all edits dirs which are required. If any shared edits dirs are
+   * configured, these are also included in the set of required dirs.
+   * 
+   * @param conf the HDFS configuration.
+   * @return all required dirs.
+   */
   public static Collection<URI> getRequiredNamespaceEditsDirs(Configuration conf) {
-    return getStorageDirs(conf, DFS_NAMENODE_EDITS_DIR_REQUIRED_KEY);
+    Set<URI> ret = new HashSet<URI>();
+    ret.addAll(getStorageDirs(conf, DFS_NAMENODE_EDITS_DIR_REQUIRED_KEY));
+    ret.addAll(getSharedEditsDirs(conf));
+    return ret;
   }
 
   private static Collection<URI> getStorageDirs(Configuration conf,
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestFailureOfSharedDir.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestFailureOfSharedDir.java
index 20c93b7e734..1fad704dc45 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestFailureOfSharedDir.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/ha/TestFailureOfSharedDir.java
@@ -23,6 +23,7 @@
 import java.io.IOException;
 import java.net.URI;
 import java.net.URISyntaxException;
+import java.util.Collection;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -33,14 +34,38 @@
 import org.apache.hadoop.hdfs.DFSConfigKeys;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.apache.hadoop.hdfs.MiniDFSNNTopology;
+import org.apache.hadoop.hdfs.server.namenode.FSNamesystem;
 import org.apache.hadoop.hdfs.server.namenode.NameNode;
 import org.apache.hadoop.test.GenericTestUtils;
 import org.junit.Test;
 
+import com.google.common.base.Joiner;
+
 public class TestFailureOfSharedDir {
   
   private static final Log LOG = LogFactory.getLog(TestFailureOfSharedDir.class);
 
+  /**
+   * Test that the shared edits dir is automatically added to the list of edits
+   * dirs that are marked required.
+   */
+  @Test
+  public void testSharedDirIsAutomaticallyMarkedRequired()
+      throws URISyntaxException {
+    URI foo = new URI("file:/foo");
+    URI bar = new URI("file:/bar");
+    Configuration conf = new Configuration();
+    conf.set(DFSConfigKeys.DFS_NAMENODE_EDITS_DIR_KEY, Joiner.on(",").join(foo, bar));
+    conf.set(DFSConfigKeys.DFS_NAMENODE_EDITS_DIR_REQUIRED_KEY, foo.toString());
+    assertFalse(FSNamesystem.getRequiredNamespaceEditsDirs(conf).contains(
+        bar));
+    conf.set(DFSConfigKeys.DFS_NAMENODE_SHARED_EDITS_DIR_KEY, bar.toString());
+    Collection<URI> requiredEditsDirs = FSNamesystem
+        .getRequiredNamespaceEditsDirs(conf); 
+    assertTrue(Joiner.on(",").join(requiredEditsDirs) + " does not contain " + bar,
+        requiredEditsDirs.contains(bar));
+  }
+
   /**
    * Test that marking the shared edits dir as being "required" causes the NN to
    * fail if that dir can't be accessed.
@@ -48,11 +73,9 @@ public class TestFailureOfSharedDir {
   @Test
   public void testFailureOfSharedDir() throws Exception {
     Configuration conf = new Configuration();
+    // The shared edits dir will automatically be marked required.
     URI sharedEditsUri = MiniDFSCluster.formatSharedEditsDir(
         new File(MiniDFSCluster.getBaseDirectory()), 0, 1);
-    // Mark the shared edits dir required.
-    conf.set(DFSConfigKeys.DFS_NAMENODE_EDITS_DIR_REQUIRED_KEY,
-        sharedEditsUri.toString());
     
     MiniDFSCluster cluster = null;
     try {