[java] Hadoop cluster setup - java.net.ConnectException: Connection refused

I want to setup a hadoop-cluster in pseudo-distributed mode. I managed to perform all the setup-steps, including startuping a Namenode, Datanode, Jobtracker and a Tasktracker on my machine.

Then I tried to run some exemplary programms and faced the java.net.ConnectException: Connection refused error. I stepped back to the very first steps of running some operations in standalone mode and faced the same problem.

I performed even triple-check of all the installation steps and have no idea how to fix it. (I am new to Hadoop and a beginner Ubuntu user thus I kindly ask you for "taking it into account" if providing any guide or tip).

This is the error output I keep receiving:

hduser@marta-komputer:/usr/local/hadoop$ bin/hadoop jar share/hadoop/mapreduce/hadoop-mapreduce-examples-2.6.0.jar grep input output 'dfs[a-z.]+'
15/02/22 18:23:04 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
15/02/22 18:23:04 INFO client.RMProxy: Connecting to ResourceManager at /0.0.0.0:8032
java.net.ConnectException: Call From marta-komputer/127.0.1.1 to localhost:9000 failed on connection exception: java.net.ConnectException: Connection refused; For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:408)
    at org.apache.hadoop.net.NetUtils.wrapWithMessage(NetUtils.java:791)
    at org.apache.hadoop.net.NetUtils.wrapException(NetUtils.java:731)
    at org.apache.hadoop.ipc.Client.call(Client.java:1472)
    at org.apache.hadoop.ipc.Client.call(Client.java:1399)
    at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:232)
    at com.sun.proxy.$Proxy9.delete(Unknown Source)
    at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.delete(ClientNamenodeProtocolTranslatorPB.java:521)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:187)
    at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:102)
    at com.sun.proxy.$Proxy10.delete(Unknown Source)
    at org.apache.hadoop.hdfs.DFSClient.delete(DFSClient.java:1929)
    at org.apache.hadoop.hdfs.DistributedFileSystem$12.doCall(DistributedFileSystem.java:638)
    at org.apache.hadoop.hdfs.DistributedFileSystem$12.doCall(DistributedFileSystem.java:634)
    at org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)
    at org.apache.hadoop.hdfs.DistributedFileSystem.delete(DistributedFileSystem.java:634)
    at org.apache.hadoop.examples.Grep.run(Grep.java:95)
    at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
    at org.apache.hadoop.examples.Grep.main(Grep.java:101)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:71)
    at org.apache.hadoop.util.ProgramDriver.run(ProgramDriver.java:144)
    at org.apache.hadoop.examples.ExampleDriver.main(ExampleDriver.java:74)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.apache.hadoop.util.RunJar.run(RunJar.java:221)
    at org.apache.hadoop.util.RunJar.main(RunJar.java:136)
Caused by: java.net.ConnectException: Connection refused
    at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
    at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:716)
    at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:206)
    at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:530)
    at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:494)
    at org.apache.hadoop.ipc.Client$Connection.setupConnection(Client.java:607)
    at org.apache.hadoop.ipc.Client$Connection.setupIOstreams(Client.java:705)
    at org.apache.hadoop.ipc.Client$Connection.access$2800(Client.java:368)
    at org.apache.hadoop.ipc.Client.getConnection(Client.java:1521)
    at org.apache.hadoop.ipc.Client.call(Client.java:1438)
    ... 32 more

etc/hadoop/hadoop-env.sh file:

# The java implementation to use.
export JAVA_HOME=/usr/lib/jvm/java-8-oracle

# The jsvc implementation to use. Jsvc is required to run secure datanodes
# that bind to privileged ports to provide authentication of data transfer
# protocol.  Jsvc is not required if SASL is configured for authentication of
# data transfer protocol using non-privileged ports.
#export JSVC_HOME=${JSVC_HOME}

export HADOOP_CONF_DIR=${HADOOP_CONF_DIR:-"/etc/hadoop"}

# Extra Java CLASSPATH elements.  Automatically insert capacity-scheduler.
for f in $HADOOP_HOME/contrib/capacity-scheduler/*.jar; do
  if [ "$HADOOP_CLASSPATH" ]; then
    export HADOOP_CLASSPATH=$HADOOP_CLASSPATH:$f
  else
    export HADOOP_CLASSPATH=$f
  fi
done

# The maximum amount of heap to use, in MB. Default is 1000.
#export HADOOP_HEAPSIZE=
#export HADOOP_NAMENODE_INIT_HEAPSIZE=""

# Extra Java runtime options.  Empty by default.
export HADOOP_OPTS="$HADOOP_OPTS -Djava.net.preferIPv4Stack=true"

# Command specific options appended to HADOOP_OPTS when specified
export HADOOP_NAMENODE_OPTS="-Dhadoop.security.logger=${HADOOP_SECURITY_LOGGER:-INFO,RFAS} -Dhdfs.audit.logger=${HDFS_AUDIT_LOGGER:-INFO,NullAppender} $HADOOP_NAMENODE_OPTS"
export HADOOP_DATANODE_OPTS="-Dhadoop.security.logger=ERROR,RFAS $HADOOP_DATANODE_OPTS"

export HADOOP_SECONDARYNAMENODE_OPTS="-Dhadoop.security.logger=${HADOOP_SECURITY_LOGGER:-INFO,RFAS} -Dhdfs.audit.logger=${HDFS_AUDIT_LOGGER:-INFO,NullAppender} $HADOOP_SECONDARYNAMENODE_OPTS"

export HADOOP_NFS3_OPTS="$HADOOP_NFS3_OPTS"
export HADOOP_PORTMAP_OPTS="-Xmx512m $HADOOP_PORTMAP_OPTS"

# The following applies to multiple commands (fs, dfs, fsck, distcp etc)
export HADOOP_CLIENT_OPTS="-Xmx512m $HADOOP_CLIENT_OPTS"
#HADOOP_JAVA_PLATFORM_OPTS="-XX:-UsePerfData $HADOOP_JAVA_PLATFORM_OPTS"

# On secure datanodes, user to run the datanode as after dropping privileges.
# This **MUST** be uncommented to enable secure HDFS if using privileged ports
# to provide authentication of data transfer protocol.  This **MUST NOT** be
# defined if SASL is configured for authentication of data transfer protocol
# using non-privileged ports.
export HADOOP_SECURE_DN_USER=${HADOOP_SECURE_DN_USER}

# Where log files are stored.  $HADOOP_HOME/logs by default.
#export HADOOP_LOG_DIR=${HADOOP_LOG_DIR}/$USER

# Where log files are stored in the secure data environment.
export HADOOP_SECURE_DN_LOG_DIR=${HADOOP_LOG_DIR}/${HADOOP_HDFS_USER}

# HDFS Mover specific parameters
###
# Specify the JVM options to be used when starting the HDFS Mover.
# These options will be appended to the options specified as HADOOP_OPTS
# and therefore may override any similar flags set in HADOOP_OPTS
#
# export HADOOP_MOVER_OPTS=""

###
# Advanced Users Only!
###

# The directory where pid files are stored. /tmp by default.
# NOTE: this should be set to a directory that can only be written to by 
#       the user that will run the hadoop daemons.  Otherwise there is the
#       potential for a symlink attack.
export HADOOP_PID_DIR=${HADOOP_PID_DIR}
export HADOOP_SECURE_DN_PID_DIR=${HADOOP_PID_DIR}

# A string representing this instance of hadoop. $USER by default.
export HADOOP_IDENT_STRING=$USER

.bashrc file Hadoop-related fragment:

# -- HADOOP ENVIRONMENT VARIABLES START -- #
export JAVA_HOME=/usr/lib/jvm/java-8-oracle
export HADOOP_HOME=/usr/local/hadoop
export PATH=$PATH:$HADOOP_HOME/bin
export PATH=$PATH:$HADOOP_HOME/sbin
export HADOOP_MAPRED_HOME=$HADOOP_HOME
export HADOOP_COMMON_HOME=$HADOOP_HOME
export HADOOP_HDFS_HOME=$HADOOP_HOME
export YARN_HOME=$HADOOP_HOME
export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_HOME/lib/native
export HADOOP_OPTS="-Djava.library.path=$HADOOP_HOME/lib"
# -- HADOOP ENVIRONMENT VARIABLES END -- #

/usr/local/hadoop/etc/hadoop/core-site.xml file:

<configuration>

<property>
  <name>hadoop.tmp.dir</name>
  <value>/usr/local/hadoop_tmp</value>
  <description>A base for other temporary directories.</description>
</property>

<property>
<name>fs.default.name</name>
<value>hdfs://localhost:9000</value>
</property>

</configuration>

/usr/local/hadoop/etc/hadoop/hdfs-site.xml file:

<configuration>
<property>
      <name>dfs.replication</name>
      <value>1</value>
 </property>
 <property>
      <name>dfs.namenode.name.dir</name>
      <value>file:/usr/local/hadoop_tmp/hdfs/namenode</value>
 </property>
 <property>
      <name>dfs.datanode.data.dir</name>
      <value>file:/usr/local/hadoop_tmp/hdfs/datanode</value>
 </property>
</configuration>

/usr/local/hadoop/etc/hadoop/yarn-site.xml file:

<configuration> 
<property>
      <name>yarn.nodemanager.aux-services</name>
      <value>mapreduce_shuffle</value>
</property>
<property>
      <name>yarn.nodemanager.aux-services.mapreduce.shuffle.class</name>
      <value>org.apache.hadoop.mapred.ShuffleHandler</value>
</property>
</configuration>

/usr/local/hadoop/etc/hadoop/mapred-site.xml file:

<configuration>
<property>
      <name>mapreduce.framework.name</name>
      <value>yarn</value>
</property>
<configuration>

Running hduser@marta-komputer:/usr/local/hadoop$ bin/hdfs namenode -format results in an output as follows (I substitiute some of its part with (...)):

hduser@marta-komputer:/usr/local/hadoop$ bin/hdfs namenode -format
15/02/22 18:50:47 INFO namenode.NameNode: STARTUP_MSG: 
/************************************************************
STARTUP_MSG: Starting NameNode
STARTUP_MSG:   host = marta-komputer/127.0.1.1
STARTUP_MSG:   args = [-format]
STARTUP_MSG:   version = 2.6.0
STARTUP_MSG:   classpath = /usr/local/hadoop/etc/hadoop:/usr/local/hadoop/share/hadoop/common/lib/htrace-core-3.0.4.jar:/usr/local/hadoop/share/hadoop/common/lib/commons-cli (...)2.6.0.jar:/usr/local/hadoop/share/hadoop/mapreduce/hadoop-mapreduce-client-common-2.6.0.jar:/usr/local/hadoop/share/hadoop/mapreduce/hadoop-mapreduce-client-hs-2.6.0.jar:/usr/local/hadoop/share/hadoop/mapreduce/hadoop-mapreduce-client-app-2.6.0.jar:/usr/local/hadoop/share/hadoop/mapreduce/hadoop-mapreduce-client-shuffle-2.6.0.jar:/usr/local/hadoop/contrib/capacity-scheduler/*.jar
STARTUP_MSG:   build = https://git-wip-us.apache.org/repos/asf/hadoop.git -r e3496499ecb8d220fba99dc5ed4c99c8f9e33bb1; compiled by 'jenkins' on 2014-11-13T21:10Z
STARTUP_MSG:   java = 1.8.0_31
************************************************************/
15/02/22 18:50:47 INFO namenode.NameNode: registered UNIX signal handlers for [TERM, HUP, INT]
15/02/22 18:50:47 INFO namenode.NameNode: createNameNode [-format]
15/02/22 18:50:47 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Formatting using clusterid: CID-0b65621a-eab3-47a4-bfd0-62b5596a940c
15/02/22 18:50:48 INFO namenode.FSNamesystem: No KeyProvider found.
15/02/22 18:50:48 INFO namenode.FSNamesystem: fsLock is fair:true
15/02/22 18:50:48 INFO blockmanagement.DatanodeManager: dfs.block.invalidate.limit=1000
15/02/22 18:50:48 INFO blockmanagement.DatanodeManager: dfs.namenode.datanode.registration.ip-hostname-check=true
15/02/22 18:50:48 INFO blockmanagement.BlockManager: dfs.namenode.startup.delay.block.deletion.sec is set to 000:00:00:00.000
15/02/22 18:50:48 INFO blockmanagement.BlockManager: The block deletion will start around 2015 Feb 22 18:50:48
15/02/22 18:50:48 INFO util.GSet: Computing capacity for map BlocksMap
15/02/22 18:50:48 INFO util.GSet: VM type       = 64-bit
15/02/22 18:50:48 INFO util.GSet: 2.0% max memory 889 MB = 17.8 MB
15/02/22 18:50:48 INFO util.GSet: capacity      = 2^21 = 2097152 entries
15/02/22 18:50:48 INFO blockmanagement.BlockManager: dfs.block.access.token.enable=false
15/02/22 18:50:48 INFO blockmanagement.BlockManager: defaultReplication         = 1
15/02/22 18:50:48 INFO blockmanagement.BlockManager: maxReplication             = 512
15/02/22 18:50:48 INFO blockmanagement.BlockManager: minReplication             = 1
15/02/22 18:50:48 INFO blockmanagement.BlockManager: maxReplicationStreams      = 2
15/02/22 18:50:48 INFO blockmanagement.BlockManager: shouldCheckForEnoughRacks  = false
15/02/22 18:50:48 INFO blockmanagement.BlockManager: replicationRecheckInterval = 3000
15/02/22 18:50:48 INFO blockmanagement.BlockManager: encryptDataTransfer        = false
15/02/22 18:50:48 INFO blockmanagement.BlockManager: maxNumBlocksToLog          = 1000
15/02/22 18:50:48 INFO namenode.FSNamesystem: fsOwner             = hduser (auth:SIMPLE)
15/02/22 18:50:48 INFO namenode.FSNamesystem: supergroup          = supergroup
15/02/22 18:50:48 INFO namenode.FSNamesystem: isPermissionEnabled = true
15/02/22 18:50:48 INFO namenode.FSNamesystem: HA Enabled: false
15/02/22 18:50:48 INFO namenode.FSNamesystem: Append Enabled: true
15/02/22 18:50:48 INFO util.GSet: Computing capacity for map INodeMap
15/02/22 18:50:48 INFO util.GSet: VM type       = 64-bit
15/02/22 18:50:48 INFO util.GSet: 1.0% max memory 889 MB = 8.9 MB
15/02/22 18:50:48 INFO util.GSet: capacity      = 2^20 = 1048576 entries
15/02/22 18:50:48 INFO namenode.NameNode: Caching file names occuring more than 10 times
15/02/22 18:50:48 INFO util.GSet: Computing capacity for map cachedBlocks
15/02/22 18:50:48 INFO util.GSet: VM type       = 64-bit
15/02/22 18:50:48 INFO util.GSet: 0.25% max memory 889 MB = 2.2 MB
15/02/22 18:50:48 INFO util.GSet: capacity      = 2^18 = 262144 entries
15/02/22 18:50:48 INFO namenode.FSNamesystem: dfs.namenode.safemode.threshold-pct = 0.9990000128746033
15/02/22 18:50:48 INFO namenode.FSNamesystem: dfs.namenode.safemode.min.datanodes = 0
15/02/22 18:50:48 INFO namenode.FSNamesystem: dfs.namenode.safemode.extension     = 30000
15/02/22 18:50:48 INFO namenode.FSNamesystem: Retry cache on namenode is enabled
15/02/22 18:50:48 INFO namenode.FSNamesystem: Retry cache will use 0.03 of total heap and retry cache entry expiry time is 600000 millis
15/02/22 18:50:48 INFO util.GSet: Computing capacity for map NameNodeRetryCache
15/02/22 18:50:48 INFO util.GSet: VM type       = 64-bit
15/02/22 18:50:48 INFO util.GSet: 0.029999999329447746% max memory 889 MB = 273.1 KB
15/02/22 18:50:48 INFO util.GSet: capacity      = 2^15 = 32768 entries
15/02/22 18:50:48 INFO namenode.NNConf: ACLs enabled? false
15/02/22 18:50:48 INFO namenode.NNConf: XAttrs enabled? true
15/02/22 18:50:48 INFO namenode.NNConf: Maximum size of an xattr: 16384
Re-format filesystem in Storage Directory /usr/local/hadoop_tmp/hdfs/namenode ? (Y or N) Y
15/02/22 18:50:50 INFO namenode.FSImage: Allocated new BlockPoolId: BP-948369552-127.0.1.1-1424627450316
15/02/22 18:50:50 INFO common.Storage: Storage directory /usr/local/hadoop_tmp/hdfs/namenode has been successfully formatted.
15/02/22 18:50:50 INFO namenode.NNStorageRetentionManager: Going to retain 1 images with txid >= 0
15/02/22 18:50:50 INFO util.ExitUtil: Exiting with status 0
15/02/22 18:50:50 INFO namenode.NameNode: SHUTDOWN_MSG: 
/************************************************************
SHUTDOWN_MSG: Shutting down NameNode at marta-komputer/127.0.1.1
************************************************************/

Starting dfs and yarn results in the following output:

hduser@marta-komputer:/usr/local/hadoop$ start-dfs.sh
15/02/22 18:53:05 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Starting namenodes on [localhost]
localhost: starting namenode, logging to /usr/local/hadoop/logs/hadoop-hduser-namenode-marta-komputer.out
localhost: starting datanode, logging to /usr/local/hadoop/logs/hadoop-hduser-datanode-marta-komputer.out
Starting secondary namenodes [0.0.0.0]
0.0.0.0: starting secondarynamenode, logging to /usr/local/hadoop/logs/hadoop-hduser-secondarynamenode-marta-komputer.out
15/02/22 18:53:20 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
hduser@marta-komputer:/usr/local/hadoop$ start-yarn.sh
starting yarn daemons
starting resourcemanager, logging to /usr/local/hadoop/logs/yarn-hduser-resourcemanager-marta-komputer.out
localhost: starting nodemanager, logging to /usr/local/hadoop/logs/yarn-hduser-nodemanager-marta-komputer.out

Calling jps shortly after that gives:

hduser@marta-komputer:/usr/local/hadoop$ jps
11696 ResourceManager
11842 NodeManager
11171 NameNode
11523 SecondaryNameNode
12167 Jps

netstat output:

hduser@marta-komputer:/usr/local/hadoop$ sudo netstat -lpten | grep java
tcp        0      0 0.0.0.0:8088            0.0.0.0:*               LISTEN      1001       690283      11696/java      
tcp        0      0 0.0.0.0:42745           0.0.0.0:*               LISTEN      1001       684574      11842/java      
tcp        0      0 0.0.0.0:13562           0.0.0.0:*               LISTEN      1001       680955      11842/java      
tcp        0      0 0.0.0.0:8030            0.0.0.0:*               LISTEN      1001       684531      11696/java      
tcp        0      0 0.0.0.0:8031            0.0.0.0:*               LISTEN      1001       684524      11696/java      
tcp        0      0 0.0.0.0:8032            0.0.0.0:*               LISTEN      1001       680879      11696/java      
tcp        0      0 0.0.0.0:8033            0.0.0.0:*               LISTEN      1001       687392      11696/java      
tcp        0      0 0.0.0.0:8040            0.0.0.0:*               LISTEN      1001       680951      11842/java      
tcp        0      0 127.0.0.1:9000          0.0.0.0:*               LISTEN      1001       687242      11171/java      
tcp        0      0 0.0.0.0:8042            0.0.0.0:*               LISTEN      1001       680956      11842/java      
tcp        0      0 0.0.0.0:50090           0.0.0.0:*               LISTEN      1001       690252      11523/java      
tcp        0      0 0.0.0.0:50070           0.0.0.0:*               LISTEN      1001       687239      11171/java  

/etc/hosts file:

127.0.0.1       localhost
127.0.1.1       marta-komputer

# The following lines are desirable for IPv6 capable hosts
::1     ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

====================================================

UPDATE 1.

I updated the core-site.xml and now I have:

<property>
<name>fs.default.name</name>
<value>hdfs://marta-komputer:9000</value>
</property>

but I keep receiving the error - now starting as:

15/03/01 00:59:34 INFO client.RMProxy: Connecting to ResourceManager at /0.0.0.0:8032
java.net.ConnectException: Call From marta-komputer.home/192.168.1.8 to marta-komputer:9000 failed on connection exception:     java.net.ConnectException: Connection refused; For more details see:    http://wiki.apache.org/hadoop/ConnectionRefused

I also notice that telnet localhost 9000 is not working:

hduser@marta-komputer:~$ telnet localhost 9000
Trying 127.0.0.1...
telnet: Unable to connect to remote host: Connection refused

This question is related to java hadoop configuration connectexception

The answer is


  • Stop it by-: stop-all.sh

  • format the namenode-: hadoop namenode -format

  • again start-: start-all.sh


I had the similar prolem with OP. As the terminal output suggested, I went to http://wiki.apache.org/hadoop/ConnectionRefused

I tried to change my /etc/hosts file as suggested here, i.e. remove 127.0.1.1 as OP suggested it will create another error.

So in the end, I leave it as is. The following is my /etc/hosts

127.0.0.1       localhost.localdomain   localhost
127.0.1.1       linux
# The following lines are desirable for IPv6 capable hosts
::1     ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

In the end, I found that my namenode did not started correctly, i.e. When you type sudo netstat -lpten | grep java in the terminal, there will not be any JVM process running(listening) on port 9000.

So I made two directories for namenode and datanode respectively(if you have not done so). You don't have to put where I put it, please replace it based on your hadoop directory. i.e.

mkdir -p /home/hadoopuser/hadoop-2.6.2/hdfs/namenode
mkdir -p /home/hadoopuser/hadoop-2.6.2/hdfs/datanode

I reconfigured my hdfs-site.xml.

<configuration>
    <property>
        <name>dfs.replication</name>
        <value>1</value>
    </property>
   <property>
        <name>dfs.namenode.name.dir</name>
        <value>file:/home/hadoopuser/hadoop-2.6.2/hdfs/namenode</value>
    </property>
    <property>
        <name>dfs.datanode.data.dir</name>
        <value>file:/home/hadoopuser/hadoop-2.6.2/hdfs/datanode</value>
    </property>
</configuration>

In terminal, stop your hdfs and yarn with script stop-dfs.sh and stop-yarn.sh. They are located in your hadoop directory/sbin. In my case, it's /home/hadoopuser/hadoop-2.6.2/sbin/.

Then start your hdfs and yarn with script start-dfs.sh and start-yarn.sh After it is started, type jps in your terminal to see if your JVM processes are running correctly. It should show the following.

15678 NodeManager
14982 NameNode
15347 SecondaryNameNode
23814 Jps
15119 DataNode
15548 ResourceManager

Then try to use netstat again to see if your namenode is listening to port 9000

sudo netstat -lpten | grep java

If you successfully set up the namenode, you should see the following in your terminal output.

tcp 0 0 127.0.0.1:9000 0.0.0.0:* LISTEN 1001 175157 14982/java

Then try to type the command hdfs dfs -mkdir /user/hadoopuser If this command executes sucessfully, now you can list your directory in the HDFS user directory by hdfs dfs -ls /user


For me it was that I could not cluster my zookeeper.

hdfs haadmin -getServiceState 1
active

hdfs haadmin -getServiceState 2
active

My hadoop-hdfs-zkfc-[hostname].log showed:

2017-04-14 11:46:55,351 WARN org.apache.hadoop.ha.HealthMonitor: Transport-level exception trying to monitor health of NameNode at HOST/192.168.1.55:9000: java.net.ConnectException: Connection refused Call From HOST/192.168.1.55 to HOST:9000 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused

solution:

hdfs-site.xml
  <property>
    <name>dfs.namenode.rpc-bind-host</name>
      <value>0.0.0.0</value>
  </property>

before

netstat -plunt

tcp        0      0 192.168.1.55:9000        0.0.0.0:*               LISTEN      13133/java

nmap localhost -p 9000

Starting Nmap 6.40 ( http://nmap.org ) at 2017-04-14 12:15 EDT
Nmap scan report for localhost (127.0.0.1)
Host is up (0.000047s latency).
Other addresses for localhost (not scanned): 127.0.0.1
PORT     STATE  SERVICE
9000/tcp closed cslistener

after

netstat -plunt
tcp        0      0 0.0.0.0:9000            0.0.0.0:*               LISTEN      14372/java

nmap localhost -p 9000

Starting Nmap 6.40 ( http://nmap.org ) at 2017-04-14 12:28 EDT
Nmap scan report for localhost (127.0.0.1)
Host is up (0.000039s latency).
Other addresses for localhost (not scanned): 127.0.0.1
PORT     STATE SERVICE
9000/tcp open  cslistener

Check your firewall setting and set

  <property>
  <name>fs.default.name</name>
  <value>hdfs://MachineName:9000</value>
  </property>

replace localhost to machine name


I was getting the same issue and found that OpenSSH service was not running and it was causing the issue. After starting the SSH service it worked.

To check if SSH service is running or not:

ssh localhost

To start the service, if OpenSSH is already installed:

sudo /etc/init.d/ssh start

In /etc/hosts:

  1. Add this line:

your-ip-address your-host-name

example: 192.168.1.8 master

In /etc/hosts:

  1. Delete the line with 127.0.1.1 (This will cause loopback)

  2. In your core-site, change localhost to your-ip or your-hostname

Now, restart the cluster.


Your issue is a very interesting one. Hadoop setup could be frustrating some time due to the complexity of the system and many moving parts involved. I think the issue you faced is definitely a firewall one. My hadoop cluster has similar setup. With a firewall rule added with command:

 sudo iptables -A INPUT -p tcp --dport 9000 -j REJECT

I'm able to see the exact issue:

15/03/02 23:46:10 INFO client.RMProxy: Connecting to ResourceManager at  /0.0.0.0:8032
java.net.ConnectException: Call From mybox/127.0.1.1 to localhost:9000 failed on connection exception: java.net.ConnectException: Connection refused; For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused
     at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

You can verify your firewall settings with command:

/usr/local/hadoop/etc$ sudo iptables -L
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         
REJECT     tcp  --  anywhere             anywhere             tcp dpt:9000 reject-with icmp-port-unreachable

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination   

Once the suspicious rule is identified, it could be deleted with a command like:

 sudo iptables -D INPUT -p tcp --dport 9000 -j REJECT 

Now, the connection should go through.


Hi Edit your conf/core-site.xml and change localhost to 0.0.0.0. Use the conf below. That should work.

<configuration>
  <property>
 <name>fs.default.name</name>
 <value>hdfs://0.0.0.0:9000</value>
</property>

For me these steps worked

  1. stop-all.sh
  2. hadoop namenode -format
  3. start-all.sh

I resolved the same issue by adding this property to hdfs-site.xml

<property>
  <name>fs.default.name</name>
  <value>hdfs://localhost:9000</value>
  </property>

get in $SPARK_HOME/conf, then open file spark-env.sh and add:

SPARK_MASTER_HOST= your-IP

SPARK_LOCAL_IP=127.0.0.1

Make sure HDFS is online. Start it by $HADOOP_HOME/sbin/start-dfs.sh Once you do that, your test with telnet localhost 9001should work.


hduser@marta-komputer:/usr/local/hadoop$ jps

11696 ResourceManager

11842 NodeManager

11171 NameNode

11523 SecondaryNameNode

12167 Jps

Where is your DataNode? Connection refused problem might also be due to no active DataNode. Check datanode logs for issues.

UPDATED:

For this error:

15/03/01 00:59:34 INFO client.RMProxy: Connecting to ResourceManager at /0.0.0.0:8032 java.net.ConnectException: Call From marta-komputer.home/192.168.1.8 to marta-komputer:9000 failed on connection exception: java.net.ConnectException: Connection refused; For more details see: http://wiki.apache.org/hadoop/ConnectionRefused

Add these lines in yarn-site.xml:

<property>
<name>yarn.resourcemanager.address</name>
<value>192.168.1.8:8032</value>
</property>
<property>
<name>yarn.resourcemanager.scheduler.address</name>
<value>192.168.1.8:8030</value>
</property>
<property>
<name>yarn.resourcemanager.resource-tracker.address</name>
<value>192.168.1.8:8031</value>
</property>

Restart the hadoop processes.


I am also facing same issue in Hortonworks

At the time I restart the Ambari agents and servers then the issue has been resolved.

 systemctl stop ambari-agent 

systemctl stop ambari-server

Source :Full Article With Resolution

 systemctl start ambari-agent

systemctl start ambari-server

From the netstat output you can see the process is listening on address 127.0.0.1

tcp        0      0 127.0.0.1:9000          0.0.0.0:*  ...

from the exception message you can see that it tries to connect to address 127.0.1.1

java.net.ConnectException: Call From marta-komputer/127.0.1.1 to localhost:9000 failed ...

further in the exception it's mentionend

For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused

on this page you find

Check that there isn't an entry for your hostname mapped to 127.0.0.1 or 127.0.1.1 in /etc/hosts (Ubuntu is notorious for this)

so the conclusion is to remove this line in your /etc/hosts

127.0.1.1       marta-komputer

In my experaince

15/02/22 18:23:04 WARN util.NativeCodeLoader: Unable to load native-hadoop
library for your platform... using builtin-java classes where applicable

You may have 64 bit version OS, and hadoop installation 32bit. refer this

java.net.ConnectException: Call From marta-komputer/127.0.1.1 to
localhost:9000 failed on connection exception: java.net.ConnectException: 
connection refused; For more details see:   
http://wiki.apache.org/hadoop/ConnectionRefused

this problem refers to your ssh public key authorization. please provide details about your ssh set up.

Please refer this link to check the complete steps.

also provide info if

cat $HOME/.ssh/authorized_keys

returns any result or not.


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