While running a wordcount program i am getting the following error. cloudera@localhost ~]$ hadoop jar WordCount.jar WordCount /inputnew2/inputfile.txt /output_new 18/06/09 00:29:06 INFO ipc.Client: Retrying connect to server: localhost.localdomain/127.0.0.1:8021. Already tried 0 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) 18/06/09 00:29:07 INFO ipc.Client: Retrying connect to server: localhost.localdomain/127.0.0.1:8021. Already tried 1 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) 18/06/09 00:29:08 INFO ipc.Client: Retrying connect to server: localhost.localdomain/127.0.0.1:8021. Already tried 2 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) 18/06/09 00:29:09 INFO ipc.Client: Retrying connect to server: localhost.localdomain/127.0.0.1:8021. Already tried 3 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) 18/06/09 00:29:10 INFO ipc.Client: Retrying connect to server: localhost.localdomain/127.0.0.1:8021. Already tried 4 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) 18/06/09 00:29:11 INFO ipc.Client: Retrying connect to server: localhost.localdomain/127.0.0.1:8021. Already tried 5 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) 18/06/09 00:29:12 INFO ipc.Client: Retrying connect to server: localhost.localdomain/127.0.0.1:8021. Already tried 6 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) 18/06/09 00:29:13 INFO ipc.Client: Retrying connect to server: localhost.localdomain/127.0.0.1:8021. Already tried 7 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) 18/06/09 00:29:14 INFO ipc.Client: Retrying connect to server: localhost.localdomain/127.0.0.1:8021. Already tried 8 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) 18/06/09 00:29:15 INFO ipc.Client: Retrying connect to server: localhost.localdomain/127.0.0.1:8021. Already tried 9 time(s); retry policy is RetryUpToMaximumCountWithFixedSleep(maxRetries=10, sleepTime=1 SECONDS) 18/06/09 00:29:15 ERROR security.UserGroupInformation: PriviledgedActionException as:cloudera (auth:SIMPLE) cause:java.net.ConnectException: Call From localhost.localdomain/127.0.0.1 to localhost.localdomain:8021 failed on connection exception: java.net.ConnectException: Connection refused; For more details see:  http://wiki.apache.org/hadoop/ConnectionRefused Exception in thread "main" java.net.ConnectException: Call From localhost.localdomain/127.0.0.1 to localhost.localdomain:8021 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:39)           at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)           at java.lang.reflect.Constructor.newInstance(Constructor.java:513)           at org.apache.hadoop.net.NetUtils.wrapWithMessage(NetUtils.java:782)           at org.apache.hadoop.net.NetUtils.wrapException(NetUtils.java:729)           at org.apache.hadoop.ipc.Client.call(Client.java:1241)           at org.apache.hadoop.ipc.WritableRpcEngine$Invoker.invoke(WritableRpcEngine.java:225)           at org.apache.hadoop.mapred.$Proxy10.getStagingAreaDir(Unknown Source)           at org.apache.hadoop.mapred.JobClient.getStagingAreaDir(JobClient.java:1324)           at org.apache.hadoop.mapreduce.JobSubmissionFiles.getStagingDir(JobSubmissionFiles.java:102)           at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:951)           at org.apache.hadoop.mapred.JobClient$2.run(JobClient.java:945)           at java.security.AccessController.doPrivileged(Native Method)           at javax.security.auth.Subject.doAs(Subject.java:396)           at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1408)           at org.apache.hadoop.mapred.JobClient.submitJobInternal(JobClient.java:945)           at org.apache.hadoop.mapreduce.Job.submit(Job.java:566)           at org.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:596)           at WordCount.main(WordCount.java:132)           at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)           at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)           at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)           at java.lang.reflect.Method.invoke(Method.java:597)           at org.apache.hadoop.util.RunJar.main(RunJar.java:208) Caused by: java.net.ConnectException: Connection refused           at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)           at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:599)           at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:207)           at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:528)           at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:492)           at org.apache.hadoop.ipc.Client$Connection.setupConnection(Client.java:509)           at org.apache.hadoop.ipc.Client$Connection.setupIOstreams(Client.java:603)           at org.apache.hadoop.ipc.Client$Connection.access$2100(Client.java:252)           at org.apache.hadoop.ipc.Client.getConnection(Client.java:1290)           at org.apache.hadoop.ipc.Client.call(Client.java:1208)           ... 18 more ... 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Hi, I have similiar requirement where we cannot get AD admin account due to security policy. We are using CDH 5.11.2 Express version.    Could you please help me providing steps for this approach.   Thanks in Advance.   Reards, Dinu ... View more

Thanks all and specially @GeKas < just to update that i was able to solve the issue, it was some of the lefover of enabling keberos on the cluster, i was install the oracle JDK which installed java1.7_cloudera, once i removed this package from the node, the LZO error gone. ... View more

Could you please mark it as answered so the community will be benifited ?  ... View more

Awesome ..you are right , i have successfully enabled TLS/SSL with Level -3 encryption Thank you @GeKas for all your inputs ... View more

@dpugazhe Generally the / monut in the linux servers are small.   Could you share the df -h command output of you linux box?   I would  suggest you to change the location for the parcels and logs for example if you have larger mount in your linux box called /xxxxx, change the /var/lib and /var/log to /xxxx/hadoop/lib and /xxxx/hadoop/log and the same for the parcels, as you are using cloudera manager, these changes can be done quickly. so to do that.   1- Stop cloudera manager services. 2- Move the old logs to the new partition. 3- Delete the old logs. 4- Start cloudera manager services ... View more