/**
* Copyright The Apache Software Foundation
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hbase.master;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseTestingUtility;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.HRegionInfo;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.MediumTests;
import org.apache.hadoop.hbase.MiniHBaseCluster;
import org.apache.hadoop.hbase.ServerName;
import org.apache.hadoop.hbase.client.HBaseAdmin;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.zookeeper.ZKAssign;
import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
import org.apache.zookeeper.KeeperException;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.junit.experimental.categories.Category;
/**
* Test cases for master to recover from ZK session expiry.
*/
@Category(MediumTests.class)
public class TestMasterZKSessionRecovery {
private static final HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility();
/**
* The default timeout is 5 minutes.
* Shorten it so that the test won't wait for too long.
*/
static {
Configuration conf = TEST_UTIL.getConfiguration();
conf.setLong("hbase.master.zksession.recover.timeout", 50000);
conf.setClass(HConstants.HBASE_MASTER_LOADBALANCER_CLASS,
MockLoadBalancer.class, LoadBalancer.class);
}
@Before
public void setUp() throws Exception {
// Start a cluster of one regionserver.
TEST_UTIL.startMiniCluster(1);
}
@After
public void tearDown() throws Exception {
TEST_UTIL.shutdownMiniCluster();
}
/**
* Negative test of master recovery from zk session expiry.
* <p>
* Starts with one master. Fakes the master zk session expired.
* The master should be able to come up if he is able to create
* the node as active master.
* @throws Exception
*/
@Test(timeout=10000)
public void testMasterZKSessionRecoveryFailure() throws Exception {
MiniHBaseCluster cluster = TEST_UTIL.getHBaseCluster();
HMaster m = cluster.getMaster();
m.abort("Test recovery from zk session expired",
new KeeperException.SessionExpiredException());
assertFalse(m.isStopped());
}
/**
* Positive test of master recovery from zk session expiry.
* <p>
* Starts with one master. Closes the master zk session.
* Ensures the master can recover the expired zk session.
* @throws Exception
*/
@Test(timeout=60000)
public void testMasterZKSessionRecoverySuccess() throws Exception {
MiniHBaseCluster cluster = TEST_UTIL.getHBaseCluster();
HMaster m = cluster.getMaster();
m.getZooKeeperWatcher().close();
m.abort("Test recovery from zk session expired",
new KeeperException.SessionExpiredException());
assertFalse(m.isStopped());
}
/**
* Tests that the master does not call retainAssignment after recovery from
* expired zookeeper session. Without the HBASE-6046 fix master always tries
* to assign all the user regions by calling retainAssignment.
*/
@Test
public void testRegionAssignmentAfterMasterRecoveryDueToZKExpiry() throws Exception {
MiniHBaseCluster cluster = TEST_UTIL.getHBaseCluster();
cluster.startRegionServer();
HMaster m = cluster.getMaster();
// now the cluster is up. So assign some regions.
HBaseAdmin admin = new HBaseAdmin(TEST_UTIL.getConfiguration());
byte[][] SPLIT_KEYS = new byte[][] { Bytes.toBytes("a"), Bytes.toBytes("b"),
Bytes.toBytes("c"), Bytes.toBytes("d"), Bytes.toBytes("e"), Bytes.toBytes("f"),
Bytes.toBytes("g"), Bytes.toBytes("h"), Bytes.toBytes("i"), Bytes.toBytes("j") };
String tableName = "testRegionAssignmentAfterMasterRecoveryDueToZKExpiry";
admin.createTable(new HTableDescriptor(tableName), SPLIT_KEYS);
ZooKeeperWatcher zooKeeperWatcher = HBaseTestingUtility.getZooKeeperWatcher(TEST_UTIL);
ZKAssign.blockUntilNoRIT(zooKeeperWatcher);
m.getZooKeeperWatcher().close();
MockLoadBalancer.retainAssignCalled = false;
m.abort("Test recovery from zk session expired", new KeeperException.SessionExpiredException());
assertFalse(m.isStopped());
// The recovered master should not call retainAssignment, as it is not a
// clean startup.
assertFalse("Retain assignment should not be called", MockLoadBalancer.retainAssignCalled);
}
static class MockLoadBalancer extends DefaultLoadBalancer {
static boolean retainAssignCalled = false;
@Override
public Map<ServerName, List<HRegionInfo>> retainAssignment(
Map<HRegionInfo, ServerName> regions, List<ServerName> servers) {
retainAssignCalled = true;
return super.retainAssignment(regions, servers);
}
}
/**
* Tests whether the logs are split when master recovers from a expired
* zookeeper session and an RS goes down.
*/
@Test(timeout = 60000)
public void testLogSplittingAfterMasterRecoveryDueToZKExpiry() throws IOException,
KeeperException, InterruptedException {
MiniHBaseCluster cluster = TEST_UTIL.getHBaseCluster();
cluster.startRegionServer();
HMaster m = cluster.getMaster();
// now the cluster is up. So assign some regions.
HBaseAdmin admin = new HBaseAdmin(TEST_UTIL.getConfiguration());
byte[][] SPLIT_KEYS = new byte[][] { Bytes.toBytes("1"), Bytes.toBytes("2"),
Bytes.toBytes("3"), Bytes.toBytes("4"), Bytes.toBytes("5") };
String tableName = "testLogSplittingAfterMasterRecoveryDueToZKExpiry";
HTableDescriptor htd = new HTableDescriptor(tableName);
HColumnDescriptor hcd = new HColumnDescriptor("col");
htd.addFamily(hcd);
admin.createTable(htd, SPLIT_KEYS);
ZooKeeperWatcher zooKeeperWatcher = HBaseTestingUtility.getZooKeeperWatcher(TEST_UTIL);
ZKAssign.blockUntilNoRIT(zooKeeperWatcher);
HTable table = new HTable(TEST_UTIL.getConfiguration(), tableName);
Put p = null;
int numberOfPuts = 0;
for (numberOfPuts = 0; numberOfPuts < 6; numberOfPuts++) {
p = new Put(Bytes.toBytes(numberOfPuts));
p.add(Bytes.toBytes("col"), Bytes.toBytes("ql"), Bytes.toBytes("value" + numberOfPuts));
table.put(p);
}
m.getZooKeeperWatcher().close();
m.abort("Test recovery from zk session expired", new KeeperException.SessionExpiredException());
assertFalse(m.isStopped());
cluster.getRegionServer(0).abort("Aborting");
// Without patch for HBASE-6046 this test case will always timeout
// with patch the test case should pass.
Scan scan = new Scan();
int numberOfRows = 0;
ResultScanner scanner = table.getScanner(scan);
Result[] result = scanner.next(1);
while (result != null && result.length > 0) {
numberOfRows++;
result = scanner.next(1);
}
assertEquals("Number of rows should be equal to number of puts.", numberOfPuts, numberOfRows);
}
}