org.apache.hadoop.raid.TestBlockFixer.java Source code

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/**
 * 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.raid;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.lang.management.ManagementFactory;
import java.net.URI;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Random;
import java.util.Set;

import javax.management.MBeanServer;
import javax.management.ObjectName;

import junit.framework.TestCase;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.DFSUtil;
import org.apache.hadoop.hdfs.DistributedFileSystem;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.hdfs.RaidDFSUtil;
import org.apache.hadoop.hdfs.TestDatanodeBlockScanner;
import org.apache.hadoop.hdfs.TestRaidDfs;
import org.apache.hadoop.hdfs.protocol.LocatedBlock;
import org.apache.hadoop.hdfs.protocol.Block;
import org.apache.hadoop.hdfs.protocol.LocatedBlocks;
import org.apache.hadoop.hdfs.util.InjectionEvent;
import org.apache.hadoop.mapred.MiniMRCluster;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.JobID;
import org.apache.hadoop.metrics.util.MetricsTimeVaryingLong;
import org.apache.hadoop.raid.DistBlockIntegrityMonitor.Priority;
import org.apache.hadoop.raid.DistBlockIntegrityMonitor.Worker.LostFileInfo;
import org.apache.hadoop.raid.LogUtils.LOGRESULTS;
import org.apache.hadoop.raid.LogUtils.LOGTYPES;
import org.apache.hadoop.raid.RaidHistogram.Point;
import org.apache.hadoop.util.InjectionEventI;
import org.apache.hadoop.util.InjectionHandler;
import org.apache.hadoop.util.StringUtils;
import org.junit.Test;

public class TestBlockFixer extends TestCase {
    final static Log LOG = LogFactory.getLog("org.apache.hadoop.raid.TestBlockFixer");
    final static String TEST_DIR = new File(System.getProperty("test.build.data", "build/contrib/raid/test/data"))
            .getAbsolutePath();
    final static String CHECKSUM_STORE_DIR = new File(TEST_DIR, "ckm_store." + System.currentTimeMillis())
            .getAbsolutePath();
    final static String CONFIG_FILE = new File(TEST_DIR, "test-raid.xml").getAbsolutePath();
    final static long RELOAD_INTERVAL = 1000;
    final static int NUM_DATANODES = 4;
    Configuration conf;
    String namenode = null;
    MiniDFSCluster dfsCluster = null;
    String hftp = null;
    MiniMRCluster mr = null;
    FileSystem fileSys = null;
    RaidNode cnode = null;
    String jobTrackerName = null;
    Random rand = new Random();
    static {
        ParityFilePair.disableCacheUsedInTestOnly();
    }

    class TestSendRecoveryTimeInjectionHandler extends InjectionHandler {
        @Override
        public void _processEvent(InjectionEventI event, Object... args) {
            if (event == InjectionEvent.RAID_SEND_RECOVERY_TIME) {
                if (cnode == null) {
                    return;
                }
                RaidHistogram histogram = (RaidHistogram) args[0];
                String p = (String) args[1];
                Long value = (Long) args[2];
                ArrayList<Point> points = histogram.getPointsWithGivenRecoveryTime(value);
                boolean match = false;
                for (Point pt : points) {
                    if (pt.path.equals(p)) {
                        match = true;
                        assertEquals(value, (Long) pt.value);
                        String trackingUrl = CorruptFileCounterServlet.getTrackingUrl((String) args[3], cnode);
                        assertTrue("Should get a tracking url", trackingUrl.length() > 0);
                        break;
                    }
                }
                assertTrue("We should find path " + p + " in the histogram", match);
            }
        }
    }

    public static void verifyMetrics(FileSystem fileSys, RaidNode cnode, boolean local, long expectedFixedFiles,
            long expectedFixBlocks) {
        assertTrue("Fewer expected fixed files",
                cnode.blockIntegrityMonitor.getNumFilesFixed() >= expectedFixedFiles);
        if (!local) {
            verifyMetrics(fileSys, cnode, LOGTYPES.OFFLINE_RECONSTRUCTION_BLOCK, LOGRESULTS.SUCCESS, null,
                    expectedFixBlocks, true);
        }
    }

    public static void verifyMetrics(FileSystem fileSys, RaidNode cnode, LOGTYPES type, LOGRESULTS result,
            long expected, boolean greater) {
        verifyMetrics(fileSys, cnode, type, result, null, expected, greater);
    }

    public static void verifyMetrics(FileSystem fileSys, RaidNode cnode, LOGTYPES type, LOGRESULTS result,
            String tag, long expected, boolean greater) {
        String counterName = LogUtils.getCounterName(fileSys, type, result, tag);
        Map<String, MetricsTimeVaryingLong> logMetrics = RaidNodeMetrics
                .getInstance(RaidNodeMetrics.DEFAULT_NAMESPACE_ID).logMetrics;
        String message = "expect " + expected + (greater ? " >= " : " = ") + counterName;
        long actual = 0L;
        synchronized (logMetrics) {
            if (expected == 0L) {
                if (greater == false) {
                    assertTrue(message, !logMetrics.containsKey(counterName));
                } else {
                    actual = logMetrics.containsKey(counterName)
                            ? logMetrics.get(counterName).getCurrentIntervalValue()
                            : 0;
                    assertTrue(message + " but " + actual, actual >= 0L);
                }
            } else {
                actual = logMetrics.get(counterName).getCurrentIntervalValue();
                if (greater == false) {
                    assertEquals(message + " but " + actual, new Long(expected), new Long(actual));
                } else {
                    assertTrue(message + " but " + actual, actual >= expected);
                }
            }
        }
    }

    public static void setChecksumStoreConfig(Configuration conf) {
        conf.set(RaidNode.RAID_CHECKSUM_STORE_CLASS_KEY, "org.apache.hadoop.raid.LocalChecksumStore");
        conf.setBoolean(RaidNode.RAID_CHECKSUM_STORE_REQUIRED_KEY, true);
        conf.set(LocalChecksumStore.LOCAL_CHECK_STORE_DIR_KEY, CHECKSUM_STORE_DIR);
    }

    @Test
    public void testPriorityEnum() {
        // Verify proper ordering of in-place values 
        assertTrue(Priority.HIGH.higherThan(Priority.LOW));
        assertTrue(Priority.LOW.higherThan(Priority.LOWEST));

        // Verify ordering of higherThan (guards against bad additions)
        int i = 0;
        for (Priority p : Priority.values()) {
            int j = 0;
            for (Priority q : Priority.values()) {
                boolean gt = p.higherThan(q);

                if (i > j) {
                    assertTrue("Priority.gt() returned a bad value", gt);
                } else {
                    assertFalse("Priority.gt() returned a bad value", gt);
                }

                j--;
            }
            i--;
        }
    }

    @Test
    public void testFilterUnfixableFiles() throws Exception {
        conf = new Configuration();
        dfsCluster = new MiniDFSCluster(conf, NUM_DATANODES, true, null);
        dfsCluster.waitActive();
        FileSystem fs = dfsCluster.getFileSystem();

        Utils.loadTestCodecs(conf);
        try {
            Configuration testConf = fs.getConf();
            BlockIntegrityMonitor blockFixer = new LocalBlockIntegrityMonitor(testConf, false);

            String p1 = "/user/foo/f1";
            String p2 = "/user/foo/f2";
            String p3 = "/user/foo/bar/f1";
            String p4 = "/raid/user/foo";
            String p5 = "/raidrs/user/foo/bar";
            fs.mkdirs(new Path(p4));

            List<String> fileList = new ArrayList<String>();
            fileList.add(p1);
            fileList.add(p2);
            fileList.add(p3);

            blockFixer.filterUnreconstructableSourceFiles(fs, fileList.iterator());
            // p3 should be filtered out.
            assertEquals(2, fileList.size());

            Set<String> filtered = new HashSet<String>();
            for (String p : fileList)
                filtered.add(p);
            assertFalse("File not filtered", filtered.contains(p3));

            fileList.add(p3);
            fs.mkdirs(new Path(p5));
            blockFixer.filterUnreconstructableSourceFiles(fs, fileList.iterator());
            // Nothing is filtered.
            assertEquals(3, fileList.size());
        } finally {
            dfsCluster.shutdown();
        }
    }

    /**
     * Test the filtering of trash files from the list of corrupt files.
     */
    @Test
    public void testTrashFilter() {
        List<String> files = new LinkedList<String>();
        // Paths that do not match the trash pattern.
        String p1 = "/user/raid/raidtest/f1";
        String p2 = "/user/.Trash/";
        // Paths that match the trash pattern.
        String p3 = "/user/raid/.Trash/raidtest/f1";
        String p4 = "/user/raid/.Trash/";
        String p5 = "/tmp/foo";
        files.add(p1);
        files.add(p3);
        files.add(p4);
        files.add(p2);
        files.add(p5);

        Configuration conf = new Configuration();
        RaidUtils.filterTrash(conf, files);

        assertEquals("expected 2 non-trash files but got " + files.size(), 2, files.size());
        for (String p : files) {
            assertTrue("wrong file returned by filterTrash", p == p1 || p == p2);
        }
    }

    @Test
    public void testBlockFixDist() throws Exception {
        implBlockFix(false, false);
    }

    @Test
    public void testBlockFixLocal() throws Exception {
        implBlockFix(true, false);
    }

    private void verifyMXBean(RaidNode cnode) throws Exception {
        MBeanServer mbs = ManagementFactory.getPlatformMBeanServer();
        ObjectName mxbeanName = new ObjectName("hadoop:service=RaidNode,name=RaidNodeState");
        Long timeSinceLastSuccessfulFix = (Long) mbs.getAttribute(mxbeanName, "TimeSinceLastSuccessfulFix");
        assertNotNull(timeSinceLastSuccessfulFix);
        if (timeSinceLastSuccessfulFix == 0) {
            assertEquals("No files need to fix", 0, cnode.blockIntegrityMonitor.approximateNumRecoverableFiles);
        }
        LOG.info("timeSinceLastSuccessfulFix:" + timeSinceLastSuccessfulFix + "\t"
                + "approximateNumRecoverableFiles:" + cnode.blockIntegrityMonitor.approximateNumRecoverableFiles
                + "\t" + "lastSuccessfulFixTime:" + cnode.blockIntegrityMonitor.lastSuccessfulFixTime);
    }

    /**
     * Create a file with three stripes, corrupt a block each in two stripes,
     * and wait for the the file to be fixed.
     */
    public void implBlockFix(boolean local, boolean hasChecksumStore) throws Exception {
        LOG.info("Test testBlockFix started.");
        long blockSize = 8192L;
        int stripeLength = 3;
        mySetup(stripeLength, -1); // never har
        Path file1 = new Path("/user/dhruba/raidtest/file1");
        Path destPath = new Path("/destraid/user/dhruba/raidtest");
        long crc1 = TestRaidDfs.createTestFilePartialLastBlock(fileSys, file1, 1, 7, blockSize);
        long file1Len = fileSys.getFileStatus(file1).getLen();
        LOG.info("Test testBlockFix created test files");

        // create an instance of the RaidNode
        Configuration localConf = new Configuration(conf);
        localConf.setInt("raid.blockfix.interval", 1000);
        if (local) {
            localConf.set("raid.blockfix.classname", "org.apache.hadoop.raid.LocalBlockIntegrityMonitor");
        } else {
            localConf.set("raid.blockfix.classname", "org.apache.hadoop.raid.DistBlockIntegrityMonitor");
            InjectionHandler h = new TestSendRecoveryTimeInjectionHandler();
            InjectionHandler.set(h);
        }
        localConf.setLong("raid.blockfix.filespertask", 2L);
        if (hasChecksumStore) {
            TestBlockFixer.setChecksumStoreConfig(localConf);
        }

        try {
            cnode = RaidNode.createRaidNode(null, localConf);
            TestRaidDfs.waitForFileRaided(LOG, fileSys, file1, destPath);
            LOG.info("Startup raidnode");
            verifyMXBean(cnode);
            cnode.stop();
            cnode.join();

            FileStatus srcStat = fileSys.getFileStatus(file1);
            DistributedFileSystem dfs = (DistributedFileSystem) fileSys;
            LocatedBlocks locs = RaidDFSUtil.getBlockLocations(dfs, file1.toUri().getPath(), 0, srcStat.getLen());

            String[] corruptFiles = DFSUtil.getCorruptFiles(dfs);
            assertEquals("no corrupt files expected", 0, corruptFiles.length);
            assertEquals("filesFixed() should return 0 before fixing files", 0,
                    cnode.blockIntegrityMonitor.getNumFilesFixed());

            // Corrupt blocks in two different stripes. We can fix them.
            int[] corruptBlockIdxs = new int[] { 0, 4, 6 };
            for (int idx : corruptBlockIdxs)
                corruptBlock(locs.get(idx).getBlock(), dfsCluster);
            RaidDFSUtil.reportCorruptBlocks(dfs, file1, corruptBlockIdxs, blockSize);

            corruptFiles = DFSUtil.getCorruptFiles(dfs);
            assertEquals("file not corrupted", 1, corruptFiles.length);
            assertEquals("wrong file corrupted", corruptFiles[0], file1.toUri().getPath());
            assertEquals("wrong number of corrupt blocks", 3,
                    RaidDFSUtil.corruptBlocksInFile(dfs, file1.toUri().getPath(), 0, srcStat.getLen()).size());

            cnode = RaidNode.createRaidNode(null, localConf);
            long start = System.currentTimeMillis();
            while ((cnode.blockIntegrityMonitor.getNumFilesFixed() < 1
                    || cnode.blockIntegrityMonitor.getNumberOfPoints("/") < 1)
                    && System.currentTimeMillis() - start < 120000) {
                LOG.info("Test testBlockFix waiting for files to be fixed.");
                verifyMXBean(cnode);
                Thread.sleep(1000);
            }
            LOG.info("Files should be fixed");
            verifyMXBean(cnode);
            assertTrue("Raidnode should record more than 1 point",
                    cnode.blockIntegrityMonitor.getNumberOfPoints("/") >= 1);
            verifyMetrics(fileSys, cnode, local, 1L, corruptBlockIdxs.length);

            dfs = getDFS(conf, dfs);
            assertTrue("file not fixed", TestRaidDfs.validateFile(dfs, file1, file1Len, crc1));
            LOG.info("Finish checking");
            verifyMXBean(cnode);
        } catch (Exception e) {
            LOG.info("Test testBlockFix Exception " + e + StringUtils.stringifyException(e));
            throw e;
        } finally {
            myTearDown();
        }
        LOG.info("Test testBlockFix completed.");
    }

    /**
     * Tests integrity of generated block.
     * Create a file and delete a block entirely. Wait for the block to be
     * regenerated. Now stop RaidNode and corrupt the generated block.
     * Test that corruption in the generated block can be detected by clients.
     */
    public void generatedBlockTestCommon(String testName, int blockToCorrupt, boolean local,
            boolean hasChecksumStore) throws Exception {
        LOG.info("Test " + testName + " started.");
        long blockSize = 8192L;
        int stripeLength = 3;
        mySetup(stripeLength, -1); // never har
        Path file1 = new Path("/user/dhruba/raidtest/file1");
        Path destPath = new Path("/destraid/user/dhruba/raidtest");
        long crc1 = TestRaidDfs.createTestFile(fileSys, file1, 1, 7, blockSize);
        long file1Len = fileSys.getFileStatus(file1).getLen();
        LOG.info("Test " + testName + " created test files");

        // create an instance of the RaidNode
        Configuration localConf = new Configuration(conf);
        localConf.setInt("raid.blockfix.interval", 1000);
        if (local) {
            localConf.set("raid.blockfix.classname", "org.apache.hadoop.raid.LocalBlockIntegrityMonitor");
        } else {
            localConf.set("raid.blockfix.classname", "org.apache.hadoop.raid.DistBlockIntegrityMonitor");
        }
        if (hasChecksumStore) {
            TestBlockFixer.setChecksumStoreConfig(localConf);
        }
        localConf.setLong("raid.blockfix.filespertask", 2L);
        try {
            cnode = RaidNode.createRaidNode(null, localConf);
            TestRaidDfs.waitForFileRaided(LOG, fileSys, file1, destPath);
            cnode.stop();
            cnode.join();

            FileStatus srcStat = fileSys.getFileStatus(file1);
            DistributedFileSystem dfs = (DistributedFileSystem) fileSys;
            LocatedBlocks locs = RaidDFSUtil.getBlockLocations(dfs, file1.toUri().getPath(), 0, srcStat.getLen());

            String[] corruptFiles = DFSUtil.getCorruptFiles(dfs);
            assertEquals("no corrupt files expected", 0, corruptFiles.length);
            assertEquals("filesFixed() should return 0 before fixing files", 0,
                    cnode.blockIntegrityMonitor.getNumFilesFixed());

            corruptBlock(locs.get(0).getBlock(), dfsCluster);
            RaidDFSUtil.reportCorruptBlocks(dfs, file1, new int[] { 0 }, blockSize);

            corruptFiles = DFSUtil.getCorruptFiles(dfs);
            assertEquals("file not corrupted", 1, corruptFiles.length);
            assertEquals("wrong file corrupted", corruptFiles[0], file1.toUri().getPath());

            cnode = RaidNode.createRaidNode(null, localConf);
            long start = System.currentTimeMillis();
            while ((cnode.blockIntegrityMonitor.getNumFilesFixed() < 1
                    || cnode.blockIntegrityMonitor.getNumberOfPoints("/") < 1)
                    && System.currentTimeMillis() - start < 120000) {
                LOG.info("Test " + testName + " waiting for files to be fixed.");
                Thread.sleep(1000);
            }
            verifyMetrics(fileSys, cnode, local, 1L, 1L);
            assertTrue("Raidnode should record more than 1 point",
                    cnode.blockIntegrityMonitor.getNumberOfPoints("/") >= 1);

            // Stop RaidNode
            cnode.stop();
            cnode.join();
            cnode = null;

            // The block has successfully been reconstructed.
            dfs = getDFS(conf, dfs);
            assertTrue("file not fixed", TestRaidDfs.validateFile(dfs, file1, file1Len, crc1));

            // Now corrupt the generated block.
            locs = RaidDFSUtil.getBlockLocations(dfs, file1.toUri().getPath(), 0, srcStat.getLen());
            corruptBlock(locs.get(0).getBlock(), dfsCluster);
            RaidDFSUtil.reportCorruptBlocks(dfs, file1, new int[] { 0 }, blockSize);

            try {
                Thread.sleep(5 * 1000);
            } catch (InterruptedException ignore) {
            }
            try {
                TestRaidDfs.validateFile(dfs, file1, file1Len, crc1);
                fail("Expected exception not thrown");
            } catch (org.apache.hadoop.fs.ChecksumException ce) {
            } catch (org.apache.hadoop.fs.BlockMissingException bme) {
            }
        } catch (Exception e) {
            LOG.info("Test " + testName + " Exception " + e + StringUtils.stringifyException(e));
            throw e;
        } finally {
            myTearDown();
        }
        LOG.info("Test " + testName + " completed.");
    }

    /**
     * Tests integrity of generated block.
     * Create a file and delete a block entirely. Wait for the block to be
     * regenerated. Now stop RaidNode and corrupt the generated block.
     * Test that corruption in the generated block can be detected by clients.
     */
    @Test
    public void testGeneratedBlockDist() throws Exception {
        generatedBlockTestCommon("testGeneratedBlock", 3, false, false);
    }

    /**
     * Tests integrity of generated block.
     * Create a file and delete a block entirely. Wait for the block to be
     * regenerated. Now stop RaidNode and corrupt the generated block.
     * Test that corruption in the generated block can be detected by clients.
     */
    @Test
    public void testGeneratedBlockLocal() throws Exception {
        generatedBlockTestCommon("testGeneratedBlock", 3, true, false);
    }

    /**
     * Tests integrity of generated last block.
     * Create a file and delete a block entirely. Wait for the block to be
     * regenerated. Now stop RaidNode and corrupt the generated block.
     * Test that corruption in the generated block can be detected by clients.
     */
    @Test
    public void testGeneratedLastBlockDist() throws Exception {
        generatedBlockTestCommon("testGeneratedLastBlock", 6, false, false);
    }

    /**
     * Tests integrity of generated last block.
     * Create a file and delete a block entirely. Wait for the block to be
     * regenerated. Now stop RaidNode and corrupt the generated block.
     * Test that corruption in the generated block can be detected by clients.
     */
    @Test
    public void testGeneratedLastBlockLocal() throws Exception {
        generatedBlockTestCommon("testGeneratedLastBlock", 6, true, false);
    }

    @Test
    public void testParityBlockFixDist() throws Exception {
        implParityBlockFix("testParityBlockFixDist", false, false);
    }

    @Test
    public void testParityBlockFixLocal() throws Exception {
        implParityBlockFix("testParityBlockFixLocal", true, false);
    }

    /**
     * Corrupt a parity file and wait for it to get fixed.
     */
    public void implParityBlockFix(String testName, boolean local, boolean hasChecksumStore) throws Exception {
        LOG.info("Test " + testName + " started.");
        long blockSize = 8192L;
        int stripeLength = 3;
        mySetup(stripeLength, -1); // never har
        Path file1 = new Path("/user/dhruba/raidtest/file1");
        Path destPath = new Path("/destraid/user/dhruba/raidtest");
        Path parityFile = new Path("/destraid/user/dhruba/raidtest/file1");
        TestRaidDfs.createTestFilePartialLastBlock(fileSys, file1, 1, 7, blockSize);
        LOG.info("Test " + testName + " created test files");

        // create an instance of the RaidNode
        Configuration localConf = new Configuration(conf);
        localConf.setInt("raid.blockfix.interval", 1000);
        if (local) {
            localConf.set("raid.blockfix.classname", "org.apache.hadoop.raid.LocalBlockIntegrityMonitor");
        } else {
            localConf.set("raid.blockfix.classname", "org.apache.hadoop.raid.DistBlockIntegrityMonitor");
        }
        if (hasChecksumStore) {
            TestBlockFixer.setChecksumStoreConfig(localConf);
        }
        localConf.setLong("raid.blockfix.filespertask", 2L);

        try {
            cnode = RaidNode.createRaidNode(null, localConf);
            TestRaidDfs.waitForFileRaided(LOG, fileSys, file1, destPath);
            cnode.stop();
            cnode.join();

            long parityCRC = RaidDFSUtil.getCRC(fileSys, parityFile);

            FileStatus parityStat = fileSys.getFileStatus(parityFile);
            DistributedFileSystem dfs = (DistributedFileSystem) fileSys;
            LocatedBlocks locs = RaidDFSUtil.getBlockLocations(dfs, parityFile.toUri().getPath(), 0,
                    parityStat.getLen());

            String[] corruptFiles = DFSUtil.getCorruptFiles(dfs);
            assertEquals("no corrupt files expected", 0, corruptFiles.length);
            assertEquals("filesFixed() should return 0 before fixing files", 0,
                    cnode.blockIntegrityMonitor.getNumFilesFixed());

            // Corrupt parity blocks for different stripes.
            int[] corruptBlockIdxs = new int[] { 0, 1, 2 };
            for (int idx : corruptBlockIdxs)
                corruptBlock(locs.get(idx).getBlock(), dfsCluster);
            RaidDFSUtil.reportCorruptBlocks(dfs, parityFile, corruptBlockIdxs, blockSize);

            corruptFiles = DFSUtil.getCorruptFiles(dfs);
            assertEquals("file not corrupted", 1, corruptFiles.length);
            assertEquals("wrong file corrupted", corruptFiles[0], parityFile.toUri().getPath());
            if (!local) {
                assertFalse(dfs.exists(new Path("blockfixer")));
            }
            cnode = RaidNode.createRaidNode(null, localConf);
            long start = System.currentTimeMillis();
            while ((cnode.blockIntegrityMonitor.getNumFilesFixed() < 1
                    || cnode.blockIntegrityMonitor.getNumberOfPoints("/") < 1)
                    && System.currentTimeMillis() - start < 120000) {
                LOG.info("Test " + testName + " waiting for files to be fixed.");
                Thread.sleep(1000);
            }
            assertTrue("Raidnode should record more than 1 point",
                    cnode.blockIntegrityMonitor.getNumberOfPoints("/") >= 1);

            long checkCRC = RaidDFSUtil.getCRC(fileSys, parityFile);

            assertEquals("file not fixed", parityCRC, checkCRC);
            cnode.stop();
            cnode.join();
            if (!local) {
                assertTrue("blockfixer will create /user/username/blockfixer", dfs.exists(new Path("blockfixer")));
            }
            cnode = RaidNode.createRaidNode(null, localConf);
            if (!local) {
                assertFalse("Restarting raidnode will cleanup job dir", dfs.exists(new Path("blockfixer")));
            }
        } catch (Exception e) {
            LOG.info("Test " + testName + " Exception " + e + StringUtils.stringifyException(e));
            throw e;
        } finally {
            myTearDown();
        }
        LOG.info("Test " + testName + " completed.");
    }

    @Test
    public void testParityHarBlockFixDist() throws Exception {
        implParityHarBlockFix("testParityHarBlockFixDist", false);
    }

    @Test
    public void testParityHarBlockFixLocal() throws Exception {
        implParityHarBlockFix("testParityHarBlockFixLocal", true);
    }

    private void implParityHarBlockFix(String testName, boolean local) throws Exception {
        LOG.info("Test " + testName + " started.");
        long blockSize = 8192L;
        int stripeLength = 3;
        mySetup(stripeLength, 0); // Time before har = 0 days.
        Path file1 = new Path("/user/dhruba/raidtest/file1");
        // Parity file will have 7 blocks.
        TestRaidDfs.createTestFilePartialLastBlock(fileSys, file1, 1, 20, blockSize);
        LOG.info("Test " + testName + " created test files");

        // create an instance of the RaidNode
        Configuration localConf = new Configuration(conf);
        localConf.setInt("raid.blockfix.interval", 1000);
        localConf.setInt(RaidNode.RAID_PARITY_HAR_THRESHOLD_DAYS_KEY, 0);
        if (local) {
            localConf.set("raid.blockfix.classname", "org.apache.hadoop.raid.LocalBlockIntegrityMonitor");
        } else {
            localConf.set("raid.blockfix.classname", "org.apache.hadoop.raid.DistBlockIntegrityMonitor");
        }
        localConf.setLong("raid.blockfix.filespertask", 2L);

        try {
            cnode = RaidNode.createRaidNode(null, localConf);
            Path harDirectory = new Path("/destraid/user/dhruba/raidtest/raidtest" + RaidNode.HAR_SUFFIX);
            long start = System.currentTimeMillis();
            while (System.currentTimeMillis() - start < 1000 * 120) {
                if (fileSys.exists(harDirectory)) {
                    break;
                }
                LOG.info("Test " + testName + " waiting for har");
                Thread.sleep(1000);
            }
            assertEquals(true, fileSys.exists(harDirectory));

            Path partFile = new Path(harDirectory, "part-0");
            long partCRC = RaidDFSUtil.getCRC(fileSys, partFile);
            FileStatus partStat = fileSys.getFileStatus(partFile);
            DistributedFileSystem dfs = (DistributedFileSystem) fileSys;
            LocatedBlocks locs = RaidDFSUtil.getBlockLocations(dfs, partFile.toUri().getPath(), 0,
                    partStat.getLen());
            assertEquals("wrong number of har blocks", 7, locs.getLocatedBlocks().size());
            cnode.stop();
            cnode.join();

            String[] corruptFiles = DFSUtil.getCorruptFiles(dfs);
            assertEquals("no corrupt files expected", 0, corruptFiles.length);
            assertEquals("filesFixed() should return 0 before fixing files", 0,
                    cnode.blockIntegrityMonitor.getNumFilesFixed());

            // Corrupt parity blocks for different stripes.
            int[] corruptBlockIdxs = new int[] { 0, 1, 6 };
            for (int idx : corruptBlockIdxs)
                corruptBlock(locs.get(idx).getBlock(), dfsCluster);
            RaidDFSUtil.reportCorruptBlocks(dfs, partFile, corruptBlockIdxs, partStat.getBlockSize());

            corruptFiles = DFSUtil.getCorruptFiles(dfs);
            assertEquals("file not corrupted", 1, corruptFiles.length);
            assertEquals("wrong file corrupted", corruptFiles[0], partFile.toUri().getPath());

            cnode = RaidNode.createRaidNode(null, localConf);
            start = System.currentTimeMillis();
            while ((cnode.blockIntegrityMonitor.getNumFilesFixed() < 1
                    || cnode.blockIntegrityMonitor.getNumberOfPoints("/") < 1)
                    && System.currentTimeMillis() - start < 120000) {
                LOG.info("Test " + testName + " waiting for files to be fixed.");
                Thread.sleep(1000);
            }
            assertTrue("Raidnode should record more than 1 point",
                    cnode.blockIntegrityMonitor.getNumberOfPoints("/") >= 1);

            long checkCRC = RaidDFSUtil.getCRC(fileSys, partFile);

            assertEquals("file not fixed", partCRC, checkCRC);
        } catch (Exception e) {
            LOG.info("Test " + testName + " Exception " + e + StringUtils.stringifyException(e));
            throw e;
        } finally {
            myTearDown();
        }
        LOG.info("Test " + testName + " completed.");
    }

    /**
     * tests that we can have 2 concurrent jobs fixing files 
     * (dist block fixer)
     */
    @Test
    public void testConcurrentJobs() throws Exception {
        LOG.info("Test testConcurrentJobs started.");
        long blockSize = 8192L;
        int stripeLength = 3;
        mySetup(stripeLength, -1); // never har
        Path file1 = new Path("/user/dhruba/raidtest/concurrentjobfile1");
        Path file2 = new Path("/user/dhruba/raidtest/concurrentjobfile2");
        Path destPath = new Path("/destraid/user/dhruba/raidtest");
        long crc1 = TestRaidDfs.createTestFilePartialLastBlock(fileSys, file1, 1, 20, blockSize);
        long crc2 = TestRaidDfs.createTestFilePartialLastBlock(fileSys, file2, 1, 20, blockSize);
        long file1Len = fileSys.getFileStatus(file1).getLen();
        long file2Len = fileSys.getFileStatus(file2).getLen();
        LOG.info("Test testConcurrentJobs created test files");

        // create an instance of the RaidNode
        Configuration localConf = new Configuration(conf);
        localConf.setInt("raid.blockfix.interval", 1000);
        localConf.set("raid.blockfix.classname", "org.apache.hadoop.raid.DistBlockIntegrityMonitor");
        localConf.setLong("raid.blockfix.filespertask", 2L);
        TestBlockFixer.setChecksumStoreConfig(localConf);

        try {
            cnode = RaidNode.createRaidNode(null, localConf);
            TestRaidDfs.waitForFileRaided(LOG, fileSys, file1, destPath);
            TestRaidDfs.waitForFileRaided(LOG, fileSys, file2, destPath);
            cnode.stop();
            cnode.join();

            FileStatus file1Stat = fileSys.getFileStatus(file1);
            FileStatus file2Stat = fileSys.getFileStatus(file2);
            DistributedFileSystem dfs = (DistributedFileSystem) fileSys;
            LocatedBlocks file1Loc = RaidDFSUtil.getBlockLocations(dfs, file1.toUri().getPath(), 0,
                    file1Stat.getLen());
            LocatedBlocks file2Loc = RaidDFSUtil.getBlockLocations(dfs, file2.toUri().getPath(), 0,
                    file2Stat.getLen());

            String[] corruptFiles = DFSUtil.getCorruptFiles(dfs);
            assertEquals("no corrupt files expected", 0, corruptFiles.length);
            assertEquals("filesFixed() should return 0 before fixing files", 0,
                    cnode.blockIntegrityMonitor.getNumFilesFixed());

            // corrupt file1
            int[] corruptBlockIdxs = new int[] { 0, 4, 6 };
            for (int idx : corruptBlockIdxs) {
                corruptBlock(file1Loc.get(idx).getBlock(), dfsCluster);
                RaidDFSUtil.reportCorruptBlocksToNN(dfs, new LocatedBlock[] { file1Loc.get(idx) });
            }
            RaidDFSUtil.reportCorruptBlocks(dfs, file1, corruptBlockIdxs, blockSize);

            cnode = RaidNode.createRaidNode(null, localConf);
            DistBlockIntegrityMonitor blockFixer = (DistBlockIntegrityMonitor) cnode.blockIntegrityMonitor;
            long start = System.currentTimeMillis();

            while (blockFixer.jobsRunning() < 1 && System.currentTimeMillis() - start < 240000) {
                LOG.info("Test testBlockFix waiting for fixing job 1 to start");
                Thread.sleep(10);
            }
            assertEquals("job 1 not running", 1, blockFixer.jobsRunning());

            // corrupt file2
            for (int idx : corruptBlockIdxs) {
                corruptBlock(file2Loc.get(idx).getBlock(), dfsCluster);
                RaidDFSUtil.reportCorruptBlocksToNN(dfs, new LocatedBlock[] { file2Loc.get(idx) });
            }

            corruptFiles = DFSUtil.getCorruptFiles(dfs);
            assertEquals("2 corrupt files expected", 2, corruptFiles.length);

            while (blockFixer.jobsRunning() < 2 && System.currentTimeMillis() - start < 240000) {
                LOG.info("Test testBlockFix waiting for fixing job 2 to start");
                Thread.sleep(10);
            }
            assertTrue(blockFixer.jobsRunning() >= 2);

            while ((blockFixer.getNumFilesFixed() < 2 || blockFixer.getNumberOfPoints("/") < 2)
                    && System.currentTimeMillis() - start < 240000) {
                LOG.info("Test testBlockFix waiting for files to be fixed.");
                Thread.sleep(10);
            }

            // wait for all the jobs to finish
            while (blockFixer.jobsRunning() > 0 && System.currentTimeMillis() - start < 240000) {
                LOG.info("Test testBlockFix waiting for block fixer jobs to finish.");
                Thread.sleep(10);
            }
            dfs = getDFS(conf, dfs);

            try {
                Thread.sleep(5 * 1000);
            } catch (InterruptedException ignore) {
            }
            assertTrue("files not fixed", blockFixer.getNumFilesFixed() >= 2);
            assertTrue("fixed files not recorded", blockFixer.getNumberOfPoints("/") >= 2);
            verifyMetrics(fileSys, cnode, LOGTYPES.OFFLINE_RECONSTRUCTION_BLOCK, LOGRESULTS.SUCCESS,
                    corruptBlockIdxs.length * 2, true);
            assertTrue("file not fixed", TestRaidDfs.validateFile(dfs, file1, file1Len, crc1));
            assertTrue("file not fixed", TestRaidDfs.validateFile(dfs, file2, file2Len, crc2));
        } catch (Exception e) {
            LOG.info("Test testConcurrentJobs exception " + e + StringUtils.stringifyException(e));
            throw e;
        } finally {
            myTearDown();
        }

    }

    /**
     * tests that the distributed block fixer obeys
     * the limit on how many jobs to submit simultaneously.
     */
    @Test
    public void testMaxPendingJobs() throws Exception {
        LOG.info("Test testMaxPendingJobs started.");
        long blockSize = 8192L;
        int stripeLength = 3;
        mySetup(stripeLength, -1); // never har
        Path file1 = new Path("/user/dhruba/raidtest/file1");
        Path file2 = new Path("/user/dhruba/raidtest/file2");
        Path destPath = new Path("/destraid/user/dhruba/raidtest");
        long crc1 = TestRaidDfs.createTestFilePartialLastBlock(fileSys, file1, 1, 20, blockSize);
        long crc2 = TestRaidDfs.createTestFilePartialLastBlock(fileSys, file2, 1, 20, blockSize);
        long file1Len = fileSys.getFileStatus(file1).getLen();
        long file2Len = fileSys.getFileStatus(file2).getLen();
        LOG.info("Test testMaxPendingJobs created test files");

        // create an instance of the RaidNode
        Configuration localConf = new Configuration(conf);
        localConf.setInt("raid.blockfix.interval", 1000);
        localConf.set("raid.blockfix.classname", "org.apache.hadoop.raid.DistBlockIntegrityMonitor");
        localConf.setLong("raid.blockfix.filespertask", 2L);
        localConf.setLong("raid.blockfix.maxpendingjobs", 1L);
        TestBlockFixer.setChecksumStoreConfig(localConf);

        try {
            cnode = RaidNode.createRaidNode(null, localConf);
            TestRaidDfs.waitForFileRaided(LOG, fileSys, file1, destPath);
            TestRaidDfs.waitForFileRaided(LOG, fileSys, file2, destPath);
            cnode.stop();
            cnode.join();

            FileStatus file1Stat = fileSys.getFileStatus(file1);
            FileStatus file2Stat = fileSys.getFileStatus(file2);
            DistributedFileSystem dfs = (DistributedFileSystem) fileSys;
            LocatedBlocks file1Loc = RaidDFSUtil.getBlockLocations(dfs, file1.toUri().getPath(), 0,
                    file1Stat.getLen());
            LocatedBlocks file2Loc = RaidDFSUtil.getBlockLocations(dfs, file2.toUri().getPath(), 0,
                    file2Stat.getLen());

            String[] corruptFiles = DFSUtil.getCorruptFiles(dfs);
            assertEquals("no corrupt files expected", 0, corruptFiles.length);
            assertEquals("filesFixed() should return 0 before fixing files", 0,
                    cnode.blockIntegrityMonitor.getNumFilesFixed());

            // corrupt file1
            int[] corruptBlockIdxs = new int[] { 0, 4, 6 };
            for (int idx : corruptBlockIdxs)
                corruptBlock(file1Loc.get(idx).getBlock(), dfsCluster);
            RaidDFSUtil.reportCorruptBlocks(dfs, file1, corruptBlockIdxs, blockSize);
            corruptFiles = DFSUtil.getCorruptFiles(dfs);

            cnode = RaidNode.createRaidNode(null, localConf);
            DistBlockIntegrityMonitor blockFixer = (DistBlockIntegrityMonitor) cnode.blockIntegrityMonitor;
            long start = System.currentTimeMillis();

            while (blockFixer.jobsRunning() < 1 && System.currentTimeMillis() - start < 240000) {
                LOG.info("Test testBlockFix waiting for fixing job 1 to start");
                Thread.sleep(10);
            }
            assertEquals("job not running", 1, blockFixer.jobsRunning());

            // corrupt file2
            for (int idx : corruptBlockIdxs)
                corruptBlock(file2Loc.get(idx).getBlock(), dfsCluster);
            RaidDFSUtil.reportCorruptBlocks(dfs, file2, corruptBlockIdxs, blockSize);
            corruptFiles = DFSUtil.getCorruptFiles(dfs);

            // wait until both files are fixed
            while ((blockFixer.getNumFilesFixed() < 2 || blockFixer.getNumberOfPoints("/") < 2)
                    && System.currentTimeMillis() - start < 240000) {
                // make sure the block fixer does not start a second job while
                // the first one is still running
                assertTrue("too many jobs running", blockFixer.jobsRunning() <= 1);
                Thread.sleep(10);
            }
            assertTrue("files not fixed", blockFixer.getNumFilesFixed() >= 2);
            assertTrue("files fixed not record", blockFixer.getNumberOfPoints("/") >= 2);
            verifyMetrics(fileSys, cnode, LOGTYPES.OFFLINE_RECONSTRUCTION_BLOCK, LOGRESULTS.SUCCESS,
                    corruptBlockIdxs.length * 2, true);
            dfs = getDFS(conf, dfs);

            try {
                Thread.sleep(5 * 1000);
            } catch (InterruptedException ignore) {
            }
            assertTrue("file not fixed", TestRaidDfs.validateFile(dfs, file1, file1Len, crc1));
            assertTrue("file not fixed", TestRaidDfs.validateFile(dfs, file2, file2Len, crc2));
        } catch (Exception e) {
            LOG.info("Test testMaxPendingJobs exception " + e + StringUtils.stringifyException(e));
            throw e;
        } finally {
            myTearDown();
        }

    }

    static class FakeDistBlockIntegrityMonitor extends DistBlockIntegrityMonitor {
        Map<String, List<String>> submittedJobs = new HashMap<String, List<String>>();

        FakeDistBlockIntegrityMonitor(Configuration conf) throws Exception {
            super(conf);
        }

        @Override
        void submitJob(Job job, List<String> filesInJob, Priority priority, Map<Job, List<LostFileInfo>> jobIndex,
                Map<JobID, TrackingUrlInfo> idToTrackingUrlMap) {
            LOG.info("Job " + job.getJobName() + " was submitted ");
            submittedJobs.put(job.getJobName(), filesInJob);
        }
    }

    public void testMultiplePriorities() throws Exception {
        LOG.info("Test testMultiplePriorities started.");
        Path srcFile = new Path("/home/test/file1");
        int repl = 1;
        int numBlocks = 8;
        long blockSize = 16384;
        int stripeLength = 3;
        Path destPath = new Path("/destraidrs");
        mySetup(stripeLength, -1); // never har
        Codec codec = Codec.getCodec("rs");
        LOG.info("Starting testMultiplePriorities");
        try {
            // Create test file and raid it.
            TestRaidDfs.createTestFilePartialLastBlock(fileSys, srcFile, repl, numBlocks, blockSize);
            FileStatus stat = fileSys.getFileStatus(srcFile);
            RaidNode.doRaid(conf, stat, destPath, codec, new RaidNode.Statistics(), RaidUtils.NULL_PROGRESSABLE,
                    false, repl, repl);

            // Corrupt first block of file.
            int blockIdxToCorrupt = 1;
            LOG.info("Corrupt block " + blockIdxToCorrupt + " of file " + srcFile);
            LocatedBlocks locations = getBlockLocations(srcFile, stat.getLen());
            corruptBlock(locations.get(blockIdxToCorrupt).getBlock(), dfsCluster);
            RaidDFSUtil.reportCorruptBlocks(fileSys, srcFile, new int[] { 1 }, blockSize);

            // Create Block Fixer and fix.
            FakeDistBlockIntegrityMonitor distBlockFixer = new FakeDistBlockIntegrityMonitor(conf);
            assertEquals(0, distBlockFixer.submittedJobs.size());

            // waiting for one job to submit
            long startTime = System.currentTimeMillis();
            while (System.currentTimeMillis() - startTime < 120000 && distBlockFixer.submittedJobs.size() == 0) {
                distBlockFixer.getCorruptionMonitor().checkAndReconstructBlocks();
                LOG.info("Waiting for jobs to submit");
                Thread.sleep(10000);
            }
            int submittedJob = distBlockFixer.submittedJobs.size();
            LOG.info("Already Submitted " + submittedJob + " jobs");
            assertTrue("Should submit more than 1 jobs", submittedJob >= 1);

            // Corrupt one more block.
            blockIdxToCorrupt = 4;
            LOG.info("Corrupt block " + blockIdxToCorrupt + " of file " + srcFile);
            locations = getBlockLocations(srcFile, stat.getLen());
            corruptBlock(locations.get(blockIdxToCorrupt).getBlock(), dfsCluster);
            RaidDFSUtil.reportCorruptBlocks(fileSys, srcFile, new int[] { 4 }, blockSize);

            // A new job should be submitted since two blocks are corrupt.
            startTime = System.currentTimeMillis();
            while (System.currentTimeMillis() - startTime < 120000
                    && distBlockFixer.submittedJobs.size() == submittedJob) {
                distBlockFixer.getCorruptionMonitor().checkAndReconstructBlocks();
                LOG.info("Waiting for more jobs to submit");
                Thread.sleep(10000);
            }
            LOG.info("Already Submitted " + distBlockFixer.submittedJobs.size() + " jobs");
            assertTrue("Should submit more than 1 jobs", distBlockFixer.submittedJobs.size() - submittedJob >= 1);
        } finally {
            myTearDown();
        }
    }

    public static DistributedFileSystem getDFS(Configuration conf, FileSystem dfs) throws IOException {
        Configuration clientConf = new Configuration(conf);
        clientConf.set("fs.hdfs.impl", "org.apache.hadoop.hdfs.DistributedFileSystem");
        clientConf.setBoolean("fs.hdfs.impl.disable.cache", true);
        URI dfsUri = dfs.getUri();
        FileSystem.closeAll();
        return (DistributedFileSystem) FileSystem.get(dfsUri, clientConf);
    }

    private void mySetup(int stripeLength, int timeBeforeHar) throws Exception {
        if (System.getProperty("hadoop.log.dir") == null) {
            String base = new File(".").getAbsolutePath();
            System.setProperty("hadoop.log.dir", new Path(base).toString() + "/logs");
        }

        new File(TEST_DIR).mkdirs(); // Make sure data directory exists
        conf = new Configuration();

        conf.set("raid.config.file", CONFIG_FILE);
        conf.setBoolean("raid.config.reload", true);
        conf.setLong("raid.config.reload.interval", RELOAD_INTERVAL);

        // scan all policies once every 5 second
        conf.setLong("raid.policy.rescan.interval", 5000);

        // do not use map-reduce cluster for Raiding
        conf.set("raid.classname", "org.apache.hadoop.raid.LocalRaidNode");
        conf.set("raid.server.address", "localhost:" + MiniDFSCluster.getFreePort());
        conf.set("mapred.raid.http.address", "localhost:0");
        // Make sure initial repl is smaller than NUM_DATANODES
        conf.setInt(RaidNode.RAID_PARITY_INITIAL_REPL_KEY, 1);

        Utils.loadTestCodecs(conf, stripeLength, 1, 3, "/destraid", "/destraidrs");

        conf.setBoolean("dfs.permissions", false);

        dfsCluster = new MiniDFSCluster(conf, NUM_DATANODES, true, null);
        dfsCluster.waitActive();
        fileSys = dfsCluster.getFileSystem();
        namenode = fileSys.getUri().toString();

        FileSystem.setDefaultUri(conf, namenode);
        mr = new MiniMRCluster(4, namenode, 3);
        jobTrackerName = "localhost:" + mr.getJobTrackerPort();
        hftp = "hftp://localhost.localdomain:" + dfsCluster.getNameNodePort();

        FileSystem.setDefaultUri(conf, namenode);
        conf.set("mapred.job.tracker" + "." + DistBlockIntegrityMonitor.BLOCKFIXER, jobTrackerName);

        FileWriter fileWriter = new FileWriter(CONFIG_FILE);
        fileWriter.write("<?xml version=\"1.0\"?>\n");
        String str = "<configuration> " + "<policy name = \"RaidTest1\"> "
                + "<srcPath prefix=\"/user/dhruba/raidtest\"/> " + "<codecId>xor</codecId> "
                + "<destPath> /destraid</destPath> " + "<property> " + "<name>targetReplication</name> "
                + "<value>1</value> "
                + "<description>after RAIDing, decrease the replication factor of a file to this value."
                + "</description> " + "</property> " + "<property> " + "<name>metaReplication</name> "
                + "<value>1</value> " + "<description> replication factor of parity file" + "</description> "
                + "</property> " + "<property> " + "<name>modTimePeriod</name> " + "<value>2000</value> "
                + "<description> time (milliseconds) after a file is modified to make it "
                + "a candidate for RAIDing " + "</description> " + "</property> ";
        if (timeBeforeHar >= 0) {
            str += "<property> " + "<name>time_before_har</name> " + "<value>" + timeBeforeHar + "</value> "
                    + "<description> amount of time waited before har'ing parity files" + "</description> "
                    + "</property> ";
        }

        str += "</policy>" + "</configuration>";
        fileWriter.write(str);
        fileWriter.close();
    }

    private void myTearDown() throws Exception {
        if (cnode != null) {
            cnode.stop();
            cnode.join();
        }
        if (mr != null) {
            mr.shutdown();
        }
        if (dfsCluster != null) {
            dfsCluster.shutdown();
        }
        InjectionHandler.clear();
    }

    private LocatedBlocks getBlockLocations(Path file, long length) throws IOException {
        DistributedFileSystem dfs = (DistributedFileSystem) fileSys;
        return dfs.getClient().namenode.getBlockLocations(file.toString(), 0, length);
    }

    static void corruptBlock(Block block, MiniDFSCluster dfs) throws IOException {
        boolean corrupted = false;
        for (int i = 0; i < NUM_DATANODES; i++) {
            corrupted |= TestDatanodeBlockScanner.corruptReplica(block, i, dfs);
        }
        assertTrue("could not corrupt block", corrupted);
    }
}