diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/MiniDFSCluster.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/MiniDFSCluster.java index 3e13e600b5..d8d633f2c8 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/MiniDFSCluster.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/MiniDFSCluster.java @@ -203,6 +203,8 @@ public static class Builder { private int nameNodeHttpPort = 0; private final Configuration conf; private int numDataNodes = 1; + private int[] dnHttpPorts = null; + private int[] dnIpcPorts = null; private StorageType[][] storageTypes = null; private StorageType[] storageTypes1D = null; private int storagesPerDatanode = DEFAULT_STORAGES_PER_DATANODE; @@ -277,6 +279,16 @@ public Builder numDataNodes(int val) { return this; } + public Builder setDnHttpPorts(int... ports) { + this.dnHttpPorts = ports; + return this; + } + + public Builder setDnIpcPorts(int... ports) { + this.dnIpcPorts = ports; + return this; + } + /** * Default: DEFAULT_STORAGES_PER_DATANODE */ @@ -599,7 +611,9 @@ protected MiniDFSCluster(Builder builder) throws IOException { builder.checkDataNodeHostConfig, builder.dnConfOverlays, builder.skipFsyncForTesting, - builder.useConfiguredTopologyMappingClass); + builder.useConfiguredTopologyMappingClass, + builder.dnHttpPorts, + builder.dnIpcPorts); } public static class DataNodeProperties { @@ -873,7 +887,7 @@ public MiniDFSCluster(int nameNodePort, operation, null, racks, hosts, null, simulatedCapacities, null, true, false, MiniDFSNNTopology.simpleSingleNN(nameNodePort, 0), - true, false, false, null, true, false); + true, false, false, null, true, false, null, null); } private void initMiniDFSCluster( @@ -891,7 +905,9 @@ private void initMiniDFSCluster( boolean checkDataNodeHostConfig, Configuration[] dnConfOverlays, boolean skipFsyncForTesting, - boolean useConfiguredTopologyMappingClass) + boolean useConfiguredTopologyMappingClass, + int[] dnHttpPorts, + int[] dnIpcPorts) throws IOException { boolean success = false; try { @@ -974,9 +990,9 @@ private void initMiniDFSCluster( // Start the DataNodes startDataNodes(conf, numDataNodes, storageTypes, manageDataDfsDirs, - dnStartOpt != null ? dnStartOpt : startOpt, - racks, hosts, storageCapacities, simulatedCapacities, setupHostsFile, - checkDataNodeAddrConfig, checkDataNodeHostConfig, dnConfOverlays); + dnStartOpt != null ? dnStartOpt : startOpt, racks, hosts, storageCapacities, + simulatedCapacities, setupHostsFile, checkDataNodeAddrConfig, checkDataNodeHostConfig, + dnConfOverlays, dnHttpPorts, dnIpcPorts); waitClusterUp(); //make sure ProxyUsers uses the latest conf ProxyUsers.refreshSuperUserGroupsConfiguration(conf); @@ -1598,8 +1614,8 @@ public synchronized void startDataNodes(Configuration conf, int numDataNodes, String[] racks, String[] hosts, long[] simulatedCapacities, boolean setupHostsFile) throws IOException { - startDataNodes(conf, numDataNodes, null, manageDfsDirs, operation, racks, hosts, - null, simulatedCapacities, setupHostsFile, false, false, null); + startDataNodes(conf, numDataNodes, null, manageDfsDirs, operation, racks, hosts, null, + simulatedCapacities, setupHostsFile, false, false, null, null, null); } public synchronized void startDataNodes(Configuration conf, int numDataNodes, @@ -1608,14 +1624,14 @@ public synchronized void startDataNodes(Configuration conf, int numDataNodes, long[] simulatedCapacities, boolean setupHostsFile, boolean checkDataNodeAddrConfig) throws IOException { - startDataNodes(conf, numDataNodes, null, manageDfsDirs, operation, racks, hosts, - null, simulatedCapacities, setupHostsFile, checkDataNodeAddrConfig, false, null); + startDataNodes(conf, numDataNodes, null, manageDfsDirs, operation, racks, hosts, null, + simulatedCapacities, setupHostsFile, checkDataNodeAddrConfig, false, null, null, null); } /** * Modify the config and start up additional DataNodes. The info port for * DataNodes is guaranteed to use a free port. - * + * * Data nodes can run with the name node in the mini cluster or * a real name node. For example, running with a real name node is useful * when running simulated data nodes with a real name node. @@ -1625,6 +1641,7 @@ public synchronized void startDataNodes(Configuration conf, int numDataNodes, * @param conf the base configuration to use in starting the DataNodes. This * will be modified as necessary. * @param numDataNodes Number of DataNodes to start; may be zero + * @param storageTypes Storage Types for DataNodes. * @param manageDfsDirs if true, the data directories for DataNodes will be * created and {@link DFSConfigKeys#DFS_DATANODE_DATA_DIR_KEY} will be * set in the conf @@ -1632,13 +1649,16 @@ public synchronized void startDataNodes(Configuration conf, int numDataNodes, * or StartupOption.FORMAT, then StartupOption.REGULAR will be used. * @param racks array of strings indicating the rack that each DataNode is on * @param hosts array of strings indicating the hostnames for each DataNode + * @param storageCapacities array of Storage Capacities to be used while testing. * @param simulatedCapacities array of capacities of the simulated data nodes * @param setupHostsFile add new nodes to dfs hosts files * @param checkDataNodeAddrConfig if true, only set DataNode port addresses if not already set in config * @param checkDataNodeHostConfig if true, only set DataNode hostname key if not already set in config * @param dnConfOverlays An array of {@link Configuration} objects that will overlay the * global MiniDFSCluster Configuration for the corresponding DataNode. - * @throws IllegalStateException if NameNode has been shutdown + * @param dnHttpPorts An array of Http ports if present, to be used for DataNodes. + * @param dnIpcPorts An array of Ipc ports if present, to be used for DataNodes. + * @throws IOException If the DFS daemons experience some issues. */ public synchronized void startDataNodes(Configuration conf, int numDataNodes, StorageType[][] storageTypes, boolean manageDfsDirs, StartupOption operation, @@ -1648,7 +1668,9 @@ public synchronized void startDataNodes(Configuration conf, int numDataNodes, boolean setupHostsFile, boolean checkDataNodeAddrConfig, boolean checkDataNodeHostConfig, - Configuration[] dnConfOverlays) throws IOException { + Configuration[] dnConfOverlays, + int[] dnHttpPorts, + int[] dnIpcPorts) throws IOException { assert storageCapacities == null || simulatedCapacities == null; assert storageTypes == null || storageTypes.length == numDataNodes; assert storageCapacities == null || storageCapacities.length == numDataNodes; @@ -1656,6 +1678,19 @@ public synchronized void startDataNodes(Configuration conf, int numDataNodes, if (operation == StartupOption.RECOVER) { return; } + + if (dnHttpPorts != null && dnHttpPorts.length != numDataNodes) { + throw new IllegalArgumentException( + "Num of http ports (" + dnHttpPorts.length + ") should match num of DataNodes (" + + numDataNodes + ")"); + } + + if (dnIpcPorts != null && dnIpcPorts.length != numDataNodes) { + throw new IllegalArgumentException( + "Num of ipc ports (" + dnIpcPorts.length + ") should match num of DataNodes (" + + numDataNodes + ")"); + } + if (checkDataNodeHostConfig) { conf.setIfUnset(DFS_DATANODE_HOST_NAME_KEY, "127.0.0.1"); } else { @@ -1711,7 +1746,15 @@ public synchronized void startDataNodes(Configuration conf, int numDataNodes, dnConf.addResource(dnConfOverlays[i]); } // Set up datanode address - setupDatanodeAddress(dnConf, setupHostsFile, checkDataNodeAddrConfig); + int httpPort = 0; + int ipcPort = 0; + if(dnHttpPorts != null) { + httpPort = dnHttpPorts[i - curDatanodesNum]; + } + if(dnIpcPorts != null) { + ipcPort = dnIpcPorts[i - curDatanodesNum]; + } + setupDatanodeAddress(dnConf, setupHostsFile, checkDataNodeAddrConfig, httpPort, ipcPort); if (manageDfsDirs) { String dirs = makeDataNodeDirs(i, storageTypes == null ? null : storageTypes[i - curDatanodesNum]); @@ -3363,9 +3406,9 @@ public void setBlockRecoveryTimeout(long timeout) { timeout); } } - + protected void setupDatanodeAddress(Configuration conf, boolean setupHostsFile, - boolean checkDataNodeAddrConfig) throws IOException { + boolean checkDataNodeAddrConfig, int httpPort, int ipcPort) throws IOException { if (setupHostsFile) { String hostsFile = conf.get(DFS_HOSTS, "").trim(); if (hostsFile.length() == 0) { @@ -3388,11 +3431,11 @@ protected void setupDatanodeAddress(Configuration conf, boolean setupHostsFile, } } if (checkDataNodeAddrConfig) { - conf.setIfUnset(DFS_DATANODE_HTTP_ADDRESS_KEY, "127.0.0.1:0"); - conf.setIfUnset(DFS_DATANODE_IPC_ADDRESS_KEY, "127.0.0.1:0"); + conf.setIfUnset(DFS_DATANODE_HTTP_ADDRESS_KEY, "127.0.0.1:" + httpPort); + conf.setIfUnset(DFS_DATANODE_IPC_ADDRESS_KEY, "127.0.0.1:" + ipcPort); } else { - conf.set(DFS_DATANODE_HTTP_ADDRESS_KEY, "127.0.0.1:0"); - conf.set(DFS_DATANODE_IPC_ADDRESS_KEY, "127.0.0.1:0"); + conf.set(DFS_DATANODE_HTTP_ADDRESS_KEY, "127.0.0.1:" + httpPort); + conf.set(DFS_DATANODE_IPC_ADDRESS_KEY, "127.0.0.1:" + ipcPort); } } diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/MiniDFSClusterWithNodeGroup.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/MiniDFSClusterWithNodeGroup.java index 8b4e9e5ef7..f7d1cb10e8 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/MiniDFSClusterWithNodeGroup.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/MiniDFSClusterWithNodeGroup.java @@ -118,7 +118,7 @@ public synchronized void startDataNodes(Configuration conf, int numDataNodes, for (int i = curDatanodesNum; i < curDatanodesNum+numDataNodes; i++) { Configuration dnConf = new HdfsConfiguration(conf); // Set up datanode address - setupDatanodeAddress(dnConf, setupHostsFile, checkDataNodeAddrConfig); + setupDatanodeAddress(dnConf, setupHostsFile, checkDataNodeAddrConfig, 0, 0); if (manageDfsDirs) { String dirs = makeDataNodeDirs(i, storageTypes == null ? null : storageTypes[i]); dnConf.set(DFSConfigKeys.DFS_DATANODE_DATA_DIR_KEY, dirs); @@ -235,7 +235,9 @@ public synchronized void startDataNodes(Configuration conf, int numDataNodes, boolean setupHostsFile, boolean checkDataNodeAddrConfig, boolean checkDataNodeHostConfig, - Configuration[] dnConfOverlays) throws IOException { + Configuration[] dnConfOverlays, + int[] dnHttpPorts, + int[] dnIpcPorts) throws IOException { startDataNodes(conf, numDataNodes, storageTypes, manageDfsDirs, operation, racks, NODE_GROUPS, hosts, storageCapacities, simulatedCapacities, setupHostsFile, checkDataNodeAddrConfig, checkDataNodeHostConfig); diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestMiniDFSCluster.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestMiniDFSCluster.java index 737795b88d..0b6d07bc2f 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestMiniDFSCluster.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestMiniDFSCluster.java @@ -19,6 +19,7 @@ package org.apache.hadoop.hdfs; import static org.apache.hadoop.hdfs.DFSConfigKeys.DFS_NAMENODE_HTTP_ADDRESS_KEY; +import static org.assertj.core.api.Assertions.assertThat; import static org.junit.Assert.assertEquals; import static org.junit.Assume.assumeTrue; @@ -26,6 +27,7 @@ import java.io.IOException; import java.util.ArrayList; import java.util.Random; +import java.util.Set; import java.util.UUID; import java.util.concurrent.TimeoutException; @@ -38,9 +40,13 @@ import org.apache.hadoop.hdfs.server.datanode.DataNode; import org.apache.hadoop.hdfs.server.datanode.fsdataset.FsDatasetSpi; import org.apache.hadoop.hdfs.server.datanode.fsdataset.impl.FsVolumeImpl; +import org.apache.hadoop.net.NetUtils; +import org.apache.hadoop.test.LambdaTestUtils; import org.apache.hadoop.test.PathUtils; import org.junit.Before; import org.junit.Test; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; import org.apache.hadoop.util.Preconditions; @@ -52,6 +58,8 @@ */ public class TestMiniDFSCluster { + private static final Logger LOG = LoggerFactory.getLogger(TestMiniDFSCluster.class); + private static final String CLUSTER_1 = "cluster1"; private static final String CLUSTER_2 = "cluster2"; private static final String CLUSTER_3 = "cluster3"; @@ -319,4 +327,88 @@ public void testSetUpFederatedCluster() throws Exception { cluster.restartNameNode(1); } } + + // There is a possibility that this test might fail if any other concurrently running + // test could bind same port as one of the ports returned by NetUtils.getFreeSocketPorts(6) + // before datanodes are started. + @Test + public void testStartStopWithPorts() throws Exception { + Configuration conf = new Configuration(); + + LambdaTestUtils.intercept( + IllegalArgumentException.class, + "Num of http ports (1) should match num of DataNodes (3)", + "MiniJournalCluster port validation failed", + () -> { + new MiniDFSCluster.Builder(conf).numDataNodes(3).setDnHttpPorts(8481).build(); + }); + + LambdaTestUtils.intercept( + IllegalArgumentException.class, + "Num of ipc ports (2) should match num of DataNodes (1)", + "MiniJournalCluster port validation failed", + () -> { + new MiniDFSCluster.Builder(conf).setDnIpcPorts(8481, 8482).build(); + }); + + LambdaTestUtils.intercept( + IllegalArgumentException.class, + "Num of ipc ports (1) should match num of DataNodes (3)", + "MiniJournalCluster port validation failed", + () -> { + new MiniDFSCluster.Builder(conf).numDataNodes(3).setDnHttpPorts(800, 9000, 10000) + .setDnIpcPorts(8481).build(); + }); + + LambdaTestUtils.intercept( + IllegalArgumentException.class, + "Num of http ports (4) should match num of DataNodes (3)", + "MiniJournalCluster port validation failed", + () -> { + new MiniDFSCluster.Builder(conf).setDnHttpPorts(800, 9000, 1000, 2000) + .setDnIpcPorts(8481, 8482, 8483).numDataNodes(3).build(); + }); + + final Set httpAndIpcPorts = NetUtils.getFreeSocketPorts(6); + LOG.info("Free socket ports: {}", httpAndIpcPorts); + + assertThat(httpAndIpcPorts).doesNotContain(0); + + final int[] httpPorts = new int[3]; + final int[] ipcPorts = new int[3]; + int httpPortIdx = 0; + int ipcPortIdx = 0; + for (Integer httpAndIpcPort : httpAndIpcPorts) { + if (httpPortIdx < 3) { + httpPorts[httpPortIdx++] = httpAndIpcPort; + } else { + ipcPorts[ipcPortIdx++] = httpAndIpcPort; + } + } + + LOG.info("Http ports selected: {}", httpPorts); + LOG.info("Ipc ports selected: {}", ipcPorts); + + try (MiniDFSCluster miniDfsCluster = new MiniDFSCluster.Builder(conf) + .setDnHttpPorts(httpPorts) + .setDnIpcPorts(ipcPorts) + .numDataNodes(3).build()) { + miniDfsCluster.waitActive(); + + assertEquals(httpPorts[0], + miniDfsCluster.getDataNode(ipcPorts[0]).getInfoPort()); + assertEquals(httpPorts[1], + miniDfsCluster.getDataNode(ipcPorts[1]).getInfoPort()); + assertEquals(httpPorts[2], + miniDfsCluster.getDataNode(ipcPorts[2]).getInfoPort()); + + assertEquals(ipcPorts[0], + miniDfsCluster.getDataNode(ipcPorts[0]).getIpcPort()); + assertEquals(ipcPorts[1], + miniDfsCluster.getDataNode(ipcPorts[1]).getIpcPort()); + assertEquals(ipcPorts[2], + miniDfsCluster.getDataNode(ipcPorts[2]).getIpcPort()); + } + } + } diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/balancer/TestBalancerLongRunningTasks.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/balancer/TestBalancerLongRunningTasks.java index 0d6300cf05..ba36a42e0c 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/balancer/TestBalancerLongRunningTasks.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/balancer/TestBalancerLongRunningTasks.java @@ -262,7 +262,7 @@ public void testBalancerWithRamDisk() throws Exception { long[][] storageCapacities = new long[][]{{ramDiskStorageLimit, diskStorageLimit}}; cluster.startDataNodes(conf, replicationFactor, storageTypes, true, null, - null, null, storageCapacities, null, false, false, false, null); + null, null, storageCapacities, null, false, false, false, null, null, null); cluster.triggerHeartbeats(); Collection namenodes = DFSUtil.getInternalNsRpcUris(conf); diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/mover/TestMover.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/mover/TestMover.java index d78b598bd3..90353c352e 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/mover/TestMover.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/mover/TestMover.java @@ -949,7 +949,7 @@ public void testMoverWithStripedFile() throws Exception { {StorageType.ARCHIVE, StorageType.ARCHIVE}, {StorageType.ARCHIVE, StorageType.ARCHIVE}, {StorageType.ARCHIVE, StorageType.ARCHIVE}}, - true, null, null, null,capacities, null, false, false, false, null); + true, null, null, null, capacities, null, false, false, false, null, null, null); cluster.triggerHeartbeats(); // move file to ARCHIVE @@ -982,7 +982,7 @@ public void testMoverWithStripedFile() throws Exception { { StorageType.SSD, StorageType.DISK }, { StorageType.SSD, StorageType.DISK }, { StorageType.SSD, StorageType.DISK } }, - true, null, null, null, capacities, null, false, false, false, null); + true, null, null, null, capacities, null, false, false, false, null, null, null); cluster.triggerHeartbeats(); // move file blocks to ONE_SSD policy @@ -1372,7 +1372,7 @@ private void startAdditionalDNs(final Configuration conf, final MiniDFSCluster cluster) throws IOException { cluster.startDataNodes(conf, newNodesRequired, newTypes, true, null, null, - null, null, null, false, false, false, null); + null, null, null, false, false, false, null, null, null); cluster.triggerHeartbeats(); } } diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/sps/TestStoragePolicySatisfierWithStripedFile.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/sps/TestStoragePolicySatisfierWithStripedFile.java index 664f459eba..8e03640783 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/sps/TestStoragePolicySatisfierWithStripedFile.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/namenode/sps/TestStoragePolicySatisfierWithStripedFile.java @@ -186,7 +186,7 @@ public void testMoverWithFullStripe() throws Exception { {StorageType.ARCHIVE, StorageType.ARCHIVE}, {StorageType.ARCHIVE, StorageType.ARCHIVE}, {StorageType.ARCHIVE, StorageType.ARCHIVE}}, - true, null, null, null, capacities, null, false, false, false, null); + true, null, null, null, capacities, null, false, false, false, null, null, null); cluster.triggerHeartbeats(); // move file to ARCHIVE @@ -294,7 +294,7 @@ public void testWhenOnlyFewTargetNodesAreAvailableToSatisfyStoragePolicy() new StorageType[][]{ {StorageType.ARCHIVE, StorageType.ARCHIVE}, {StorageType.ARCHIVE, StorageType.ARCHIVE}}, - true, null, null, null, capacities, null, false, false, false, null); + true, null, null, null, capacities, null, false, false, false, null, null, null); cluster.triggerHeartbeats(); // Move file to ARCHIVE. Only 5 datanodes are available with ARCHIVE diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/sps/TestExternalStoragePolicySatisfier.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/sps/TestExternalStoragePolicySatisfier.java index 4c75cb3f29..7ef83c392e 100644 --- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/sps/TestExternalStoragePolicySatisfier.java +++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/server/sps/TestExternalStoragePolicySatisfier.java @@ -1712,7 +1712,7 @@ private void startAdditionalDNs(final Configuration conf, } cluster.startDataNodes(conf, newNodesRequired, newTypes, true, null, null, - null, capacities, null, false, false, false, null); + null, capacities, null, false, false, false, null, null, null); cluster.triggerHeartbeats(); } diff --git a/hadoop-tools/hadoop-dynamometer/hadoop-dynamometer-infra/src/main/java/org/apache/hadoop/tools/dynamometer/SimulatedDataNodes.java b/hadoop-tools/hadoop-dynamometer/hadoop-dynamometer-infra/src/main/java/org/apache/hadoop/tools/dynamometer/SimulatedDataNodes.java index 520077e082..0189d1fd1a 100644 --- a/hadoop-tools/hadoop-dynamometer/hadoop-dynamometer-infra/src/main/java/org/apache/hadoop/tools/dynamometer/SimulatedDataNodes.java +++ b/hadoop-tools/hadoop-dynamometer/hadoop-dynamometer-infra/src/main/java/org/apache/hadoop/tools/dynamometer/SimulatedDataNodes.java @@ -131,7 +131,7 @@ public int run(String[] args) throws Exception { + " block listing files; launching DataNodes accordingly."); mc.startDataNodes(getConf(), blockListFiles.size(), null, false, StartupOption.REGULAR, null, null, null, null, false, true, true, - null); + null, null, null); long startTime = Time.monotonicNow(); System.out.println("Waiting for DataNodes to connect to NameNode and " + "init storage directories.");