Author: szetszwo
Date: Thu Jun 28 02:48:05 2012
New Revision: 1354798
URL: http://svn.apache.org/viewvc?rev=1354798&view=rev
Log:
HDFS-3518. Add a utility method DistributedFileSystem.isHealthy(uri) for
checking if the given HDFS is healthy.
Modified:
hadoop/common/branches/branch-1/CHANGES.txt
hadoop/common/branches/branch-1/src/hdfs/org/apache/hadoop/hdfs/DistributedFileSystem.java
hadoop/common/branches/branch-1/src/test/org/apache/hadoop/hdfs/TestDFSClientRetries.java
Modified: hadoop/common/branches/branch-1/CHANGES.txt
URL:
http://svn.apache.org/viewvc/hadoop/common/branches/branch-1/CHANGES.txt?rev=1354798&r1=1354797&r2=1354798&view=diff
==============================================================================
--- hadoop/common/branches/branch-1/CHANGES.txt (original)
+++ hadoop/common/branches/branch-1/CHANGES.txt Thu Jun 28 02:48:05 2012
@@ -68,6 +68,9 @@ Release 1.1.0 - unreleased
HADOOP-8209. Add option to relax build-version check for branch-1. (eli)
+ HDFS-3518. Add a utility method DistributedFileSystem.isHealthy(uri) for
+ checking if the given HDFS is healthy. (szetszwo)
+
IMPROVEMENTS
MAPREDUCE-3597. [Rumen] Provide a way to access other info of history file
Modified:
hadoop/common/branches/branch-1/src/hdfs/org/apache/hadoop/hdfs/DistributedFileSystem.java
URL:
http://svn.apache.org/viewvc/hadoop/common/branches/branch-1/src/hdfs/org/apache/hadoop/hdfs/DistributedFileSystem.java?rev=1354798&r1=1354797&r2=1354798&view=diff
==============================================================================
---
hadoop/common/branches/branch-1/src/hdfs/org/apache/hadoop/hdfs/DistributedFileSystem.java
(original)
+++
hadoop/common/branches/branch-1/src/hdfs/org/apache/hadoop/hdfs/DistributedFileSystem.java
Thu Jun 28 02:48:05 2012
@@ -18,29 +18,40 @@
package org.apache.hadoop.hdfs;
-import java.io.*;
-import java.net.*;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.net.InetSocketAddress;
+import java.net.URI;
import java.util.ArrayList;
-import org.apache.hadoop.fs.permission.FsPermission;
-import org.apache.hadoop.fs.*;
import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
-import org.apache.hadoop.hdfs.protocol.FSConstants;
+import org.apache.hadoop.fs.BlockLocation;
+import org.apache.hadoop.fs.ContentSummary;
+import org.apache.hadoop.fs.FSDataInputStream;
+import org.apache.hadoop.fs.FSDataOutputStream;
+import org.apache.hadoop.fs.FileStatus;
+import org.apache.hadoop.fs.FileSystem;
+import org.apache.hadoop.fs.MD5MD5CRC32FileChecksum;
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.fs.permission.FsPermission;
import org.apache.hadoop.hdfs.protocol.Block;
-import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
-import org.apache.hadoop.hdfs.protocol.LocatedBlock;
+import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
import org.apache.hadoop.hdfs.protocol.DirectoryListing;
+import org.apache.hadoop.hdfs.protocol.FSConstants;
import org.apache.hadoop.hdfs.protocol.FSConstants.DatanodeReportType;
+import org.apache.hadoop.hdfs.protocol.FSConstants.SafeModeAction;
import org.apache.hadoop.hdfs.protocol.FSConstants.UpgradeAction;
+import org.apache.hadoop.hdfs.protocol.HdfsFileStatus;
+import org.apache.hadoop.hdfs.protocol.LocatedBlock;
import
org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenIdentifier;
import org.apache.hadoop.hdfs.server.common.UpgradeStatusReport;
import org.apache.hadoop.hdfs.server.namenode.NameNode;
-import org.apache.hadoop.hdfs.DFSClient.DFSOutputStream;
+import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.io.Text;
+import org.apache.hadoop.ipc.Client;
import org.apache.hadoop.security.AccessControlException;
-import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.security.token.SecretManager.InvalidToken;
+import org.apache.hadoop.security.token.Token;
import org.apache.hadoop.util.Progressable;
@@ -626,4 +637,46 @@ public class DistributedFileSystem exten
public void setBalancerBandwidth(long bandwidth) throws IOException {
dfs.setBalancerBandwidth(bandwidth);
}
+
+ /**
+ * Is the HDFS healthy?
+ * HDFS is considered as healthy if it is up and not in safemode.
+ *
+ * @param uri the HDFS URI. Note that the URI path is ignored.
+ * @return true if HDFS is healthy; false, otherwise.
+ */
+ public static boolean isHealthy(URI uri) {
+ //check scheme
+ final String scheme = uri.getScheme();
+ if (!"hdfs".equalsIgnoreCase(scheme)) {
+ throw new IllegalArgumentException("This scheme is not hdfs, uri=" +
uri);
+ }
+
+ final Configuration conf = new Configuration();
+ //disable FileSystem cache
+ conf.setBoolean(String.format("fs.%s.impl.disable.cache", scheme), true);
+ //disable client retry for rpc connection and rpc calls
+ conf.setBoolean(DFSConfigKeys.DFS_CLIENT_RETRY_POLICY_ENABLED_KEY, false);
+ conf.setInt(Client.IPC_CLIENT_CONNECT_MAX_RETRIES_KEY, 0);
+
+ DistributedFileSystem fs = null;
+ try {
+ fs = (DistributedFileSystem)FileSystem.get(uri, conf);
+ final boolean safemode = fs.setSafeMode(SafeModeAction.SAFEMODE_GET);
+ if (LOG.isDebugEnabled()) {
+ LOG.debug("Is namenode in safemode? " + safemode + "; uri=" + uri);
+ }
+
+ fs.close();
+ fs = null;
+ return !safemode;
+ } catch(IOException e) {
+ if (LOG.isDebugEnabled()) {
+ LOG.debug("Got an exception for uri=" + uri, e);
+ }
+ return false;
+ } finally {
+ IOUtils.cleanup(LOG, fs);
+ }
+ }
}
Modified:
hadoop/common/branches/branch-1/src/test/org/apache/hadoop/hdfs/TestDFSClientRetries.java
URL:
http://svn.apache.org/viewvc/hadoop/common/branches/branch-1/src/test/org/apache/hadoop/hdfs/TestDFSClientRetries.java?rev=1354798&r1=1354797&r2=1354798&view=diff
==============================================================================
---
hadoop/common/branches/branch-1/src/test/org/apache/hadoop/hdfs/TestDFSClientRetries.java
(original)
+++
hadoop/common/branches/branch-1/src/test/org/apache/hadoop/hdfs/TestDFSClientRetries.java
Thu Jun 28 02:48:05 2012
@@ -28,6 +28,7 @@ import java.io.InputStream;
import java.io.OutputStream;
import java.net.InetSocketAddress;
import java.net.SocketTimeoutException;
+import java.net.URI;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.TimeUnit;
@@ -542,9 +543,11 @@ public class TestDFSClientRetries extend
conf, numDatanodes, true, null);
try {
cluster.waitActive();
+ final DistributedFileSystem dfs =
(DistributedFileSystem)cluster.getFileSystem();
+ final URI uri = dfs.getUri();
+ assertTrue(DistributedFileSystem.isHealthy(uri));
//create a file
- final DistributedFileSystem dfs =
(DistributedFileSystem)cluster.getFileSystem();
final long length = 1L << 20;
final Path file1 = new Path(dir, "foo");
DFSTestUtil.createFile(dfs, file1, length, numDatanodes, 20120406L);
@@ -554,7 +557,9 @@ public class TestDFSClientRetries extend
assertEquals(length, s1.getLen());
//shutdown namenode
+ assertTrue(DistributedFileSystem.isHealthy(uri));
cluster.shutdownNameNode();
+ assertFalse(DistributedFileSystem.isHealthy(uri));
//namenode is down, create another file in a thread
final Path file3 = new Path(dir, "file");
@@ -579,8 +584,10 @@ public class TestDFSClientRetries extend
try {
//sleep, restart, and then wait active
TimeUnit.SECONDS.sleep(30);
+ assertFalse(DistributedFileSystem.isHealthy(uri));
cluster.restartNameNode(false, false);
cluster.waitActive();
+ assertTrue(DistributedFileSystem.isHealthy(uri));
} catch (Exception e) {
exceptions.add(e);
}
@@ -596,7 +603,9 @@ public class TestDFSClientRetries extend
assertEquals(dfs.getFileChecksum(file1), dfs.getFileChecksum(file3));
//enter safe mode
+ assertTrue(DistributedFileSystem.isHealthy(uri));
dfs.setSafeMode(SafeModeAction.SAFEMODE_ENTER);
+ assertFalse(DistributedFileSystem.isHealthy(uri));
//leave safe mode in a new thread
new Thread(new Runnable() {
@@ -605,7 +614,9 @@ public class TestDFSClientRetries extend
try {
//sleep and then leave safe mode
TimeUnit.SECONDS.sleep(30);
+ assertFalse(DistributedFileSystem.isHealthy(uri));
dfs.setSafeMode(SafeModeAction.SAFEMODE_LEAVE);
+ assertTrue(DistributedFileSystem.isHealthy(uri));
} catch (Exception e) {
exceptions.add(e);
}
@@ -616,6 +627,8 @@ public class TestDFSClientRetries extend
final Path file2 = new Path(dir, "bar");
DFSTestUtil.createFile(dfs, file2, length, numDatanodes, 20120406L);
assertEquals(dfs.getFileChecksum(file1), dfs.getFileChecksum(file2));
+
+ assertTrue(DistributedFileSystem.isHealthy(uri));
//make sure it won't retry on exceptions like FileNotFoundException
final Path nonExisting = new Path(dir, "nonExisting");
