Runing gridmix2 in hadoop 2.0.0 cannot initialize Cluster - hadoop

It's my first time using hadoop and try to run gridmix2 with it. I had installed hadoop 2.2.0 but when I try to generate data with gridmix i had the following error:
**
java.io.IOException: Cannot initialize Cluster. Please check your configuration for mapreduce.framework.name and the correspond server addresses.**
at org.apache.hadoop.mapreduce.Cluster.initialize(Cluster.java:120)
at org.apache.hadoop.mapreduce.Cluster.<init>(Cluster.java:82)
at org.apache.hadoop.mapreduce.Cluster.<init>(Cluster.java:75)
at org.apache.hadoop.mapred.JobClient.init(JobClient.java:470)
at org.apache.hadoop.mapred.JobClient.<init>(JobClient.java:460)
at org.apache.hadoop.examples.RandomTextWriter.run(RandomTextWriter.java:180)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.hadoop.examples.RandomTextWriter.main(RandomTextWriter.java:248)
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:498)
at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:72)
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:498)
at org.apache.hadoop.util.RunJar.main(RunJar.java:212)
But in my file hadoop-env.sh i found that:
**
# 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
**
and the problem is that the contrib/capacity-scheduler doesn't exist in my system.
Thanks for your help!

Related

TDCH with oozie is failing while connecting to Hive

I am trying to execute data import from Teradata to Hive using TDCH 0.15. The import is working fine while issuing a CLI command on namenode but failing with below error when integrated with oozie (using Java node). Is it because of missing library?
2016-10-10 16:36:02,743 WARN [main] org.apache.hadoop.hive.metastore.ObjectStore: Failed to get database d0_edw1_ato, returning NoSuchObjectException
2016-10-10 16:36:02,750 ERROR [main] org.apache.hadoop.hive.metastore.RetryingHMSHandler: InvalidObjectException(message:d0_edw1_ato)
at org.apache.hadoop.hive.metastore.HiveMetaStore$HMSHandler.create_table_with_environment_context(HiveMetaStore.java:1451)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.apache.hadoop.hive.metastore.RetryingHMSHandler.invoke(RetryingHMSHandler.java:107)
at com.sun.proxy.$Proxy22.create_table_with_environment_context(Unknown Source)
at org.apache.hadoop.hive.metastore.HiveMetaStoreClient.create_table_with_environment_context(HiveMetaStoreClient.java:2056)
at org.apache.hadoop.hive.metastore.HiveMetaStoreClient.createTable(HiveMetaStoreClient.java:675)
at org.apache.hadoop.hive.metastore.HiveMetaStoreClient.createTable(HiveMetaStoreClient.java:663)
at com.teradata.connector.hive.utils.HiveUtils.createHiveTable(HiveUtils.java:979)
at com.teradata.connector.hive.processor.HiveOutputProcessor.outputPostProcessor(HiveOutputProcessor.java:258)
at com.teradata.connector.common.tool.ConnectorJobRunner.runJob(ConnectorJobRunner.java:162)
at com.teradata.connector.common.tool.ConnectorImportTool.run(ConnectorImportTool.java:74)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:76)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:90)
at com.teradata.connector.common.tool.ConnectorImportTool.main(ConnectorImportTool.java:813)
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:498)
at org.apache.oozie.action.hadoop.JavaMain.run(JavaMain.java:56)
at org.apache.oozie.action.hadoop.LauncherMain.run(LauncherMain.java:47)
at org.apache.oozie.action.hadoop.JavaMain.main(JavaMain.java:35)
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:498)
at org.apache.oozie.action.hadoop.LauncherMapper.map(LauncherMapper.java:241)
at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:54)
at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:453)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:343)
at org.apache.hadoop.mapred.YarnChild$2.run(YarnChild.java:168)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1657)
at org.apache.hadoop.mapred.YarnChild.main(YarnChild.java:162)

Gobblin Kafka to HDFS pull job error

I'm trying to pull data from Kafka to HDFS using Gobblin.
Gobblin version (compiled from github source code with command sudo ./gradlew clean build -PuseHadoop2 -PhadoopVersion=2.7.1 -x test):
0.6.2-546-g431188b
Hadoop version:
Hadoop 2.7.1.2.4.2.0-258
Subversion git#github.com:hortonworks/hadoop.git -r 13debf893a605e8a88df18a7d8d214f571e05289
Compiled by jenkins on 2016-04-24T16:02Z
Compiled with protoc 2.5.0
From source with checksum 2a2d95f05ec6c3ac547ed58cab713ac
This command was run using /usr/hdp/2.4.2.0-258/hadoop/hadoop-common-2.7.1.2.4.2.0-258.jar
Gobblin job:
job.name=GobblinKafkaQuickStart
job.group=GobblinKafka
job.description=Gobblin quick start job for Kafka
job.lock.enabled=false
job.schedule=0 0/2 * * * ?
kafka.brokers=hd-mgt03:6667,hd-mgt02:6667,hd-mgt04:6667
source.class=gobblin.source.extractor.extract.kafka.KafkaSimpleSource
extract.namespace=gobblin.extract.kafka
writer.builder.class=gobblin.writer.AvroHdfsDataWriter
writer.file.path.type=tablename
writer.destination.type=HDFS
writer.output.format=AVRO
data.publisher.type=gobblin.publisher.BaseDataPublisher
mr.job.max.mappers=1
metrics.reporting.file.enabled=true
metrics.log.dir=/gobblin-kafka/metrics
metrics.reporting.file.suffix=txt
bootstrap.with.offset=earliest
fs.uri=hdfs://hdfs:8020
writer.fs.uri=hdfs://hdfs:8020
state.store.fs.uri=hdfs://hdfs:8020
mr.job.root.dir=/kafka/working
state.store.dir=/kafka/state-store
task.data.root.dir=/kafka/task-data
data.publisher.final.dir=/kafka/job-output
I'm trying to run gobblin-mapreduce.sh from gobblin-dist/bin folder, but getting error:
Exception in thread "main" gobblin.runtime.JobException: Job job_GobblinKafkaQuickStart_1464962113982 failed
at gobblin.runtime.AbstractJobLauncher.launchJob(AbstractJobLauncher.java:363)
at gobblin.runtime.mapreduce.CliMRJobLauncher.launchJob(CliMRJobLauncher.java:84)
at gobblin.runtime.mapreduce.CliMRJobLauncher.run(CliMRJobLauncher.java:61)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:84)
at gobblin.runtime.mapreduce.CliMRJobLauncher.main(CliMRJobLauncher.java:106)
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:497)
at org.apache.hadoop.util.RunJar.run(RunJar.java:221)
at org.apache.hadoop.util.RunJar.main(RunJar.java:136)
Log file contains error:
2016-06-03 16:55:17 MSK ERROR [main] gobblin.runtime.AbstractJobLauncher 321 - Failed to launch and run job job_GobblinKafkaQuickStart_1464962113982: java.lang.NoSuchFieldError: DEFAULT_MR_AM_ADMIN_USER_ENV
java.lang.NoSuchFieldError: DEFAULT_MR_AM_ADMIN_USER_ENV
at org.apache.hadoop.mapred.YARNRunner.createApplicationSubmissionContext(YARNRunner.java:470)
at org.apache.hadoop.mapred.YARNRunner.submitJob(YARNRunner.java:285)
at org.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:240)
at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1290)
at org.apache.hadoop.mapreduce.Job$10.run(Job.java:1287)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:422)
at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1657)
at org.apache.hadoop.mapreduce.Job.submit(Job.java:1287)
at gobblin.runtime.mapreduce.MRJobLauncher.runWorkUnits(MRJobLauncher.java:198)
at gobblin.runtime.AbstractJobLauncher.launchJob(AbstractJobLauncher.java:296)
at gobblin.runtime.mapreduce.CliMRJobLauncher.launchJob(CliMRJobLauncher.java:84)
at gobblin.runtime.mapreduce.CliMRJobLauncher.run(CliMRJobLauncher.java:61)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:84)
at gobblin.runtime.mapreduce.CliMRJobLauncher.main(CliMRJobLauncher.java:106)
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:497)
at org.apache.hadoop.util.RunJar.run(RunJar.java:221)
at org.apache.hadoop.util.RunJar.main(RunJar.java:136)
What could be the reason for this error? How can I fix it?
From you error I can tell it might be the problem of JAR.
Usually, this error (java.lang.NoSuchFieldError: DEFAULT_MR_AM_ADMIN_USER_ENV) is caused by jar conflicts. You can check your class path to see if there are any version conflicts.

Failing oozie launcher on yarn-cluster mode

so I'm trying to run a spark job on yarn-cluster mode (succeeded running it in local mode and yarn-client), but I am running into a problem where oozie launcher fails. Below is the error message from stderr.
Failing Oozie Launcher, Main class [org.apache.oozie.action.hadoop.JavaMain], main() threw exception, java.lang.NoSuchMethodError: org.apache.spark.network.util.JavaUtils.byteStringAsBytes(Ljava/lang/String;)J
org.apache.oozie.action.hadoop.JavaMainException: java.lang.NoSuchMethodError: org.apache.spark.network.util.JavaUtils.byteStringAsBytes(Ljava/lang/String;)J
at org.apache.oozie.action.hadoop.JavaMain.run(JavaMain.java:60)
at org.apache.oozie.action.hadoop.LauncherMain.run(LauncherMain.java:46)
at org.apache.oozie.action.hadoop.JavaMain.main(JavaMain.java:38)
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:497)
at org.apache.oozie.action.hadoop.LauncherMapper.map(LauncherMapper.java:228)
at org.apache.hadoop.mapred.MapRunner.run(MapRunner.java:54)
at org.apache.hadoop.mapred.MapTask.runOldMapper(MapTask.java:453)
at org.apache.hadoop.mapred.MapTask.run(MapTask.java:343)
at org.apache.hadoop.mapred.LocalContainerLauncher$EventHandler.runSubtask(LocalContainerLauncher.java:370)
at org.apache.hadoop.mapred.LocalContainerLauncher$EventHandler.runTask(LocalContainerLauncher.java:295)
at org.apache.hadoop.mapred.LocalContainerLauncher$EventHandler.access$200(LocalContainerLauncher.java:181)
at org.apache.hadoop.mapred.LocalContainerLauncher$EventHandler$1.run(LocalContainerLauncher.java:224)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NoSuchMethodError: org.apache.spark.network.util.JavaUtils.byteStringAsBytes(Ljava/lang/String;)J
at org.apache.spark.util.Utils$.memoryStringToMb(Utils.scala:993)
at org.apache.spark.util.MemoryParam$.unapply(MemoryParam.scala:27)
at org.apache.spark.deploy.yarn.ClientArguments.parseArgs(ClientArguments.scala:168)
at org.apache.spark.deploy.yarn.ClientArguments.<init>(ClientArguments.scala:58)
at org.apache.spark.deploy.yarn.Client$.main(Client.scala:966)
at org.apache.spark.deploy.yarn.Client.main(Client.scala)
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:497)
at org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:674)
at org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:180)
at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:205)
at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:120)
at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
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:497)
at org.apache.oozie.action.hadoop.JavaMain.run(JavaMain.java:57)
... 19 more
The job runs on spark 1.5.2, so I downloaded and put the spark-assembly-1.5.2-hadoop2.6.0.jar file onto HDFS, and set the spark.yarn.jar field in my spark config file to point to the jar path, and set the oozie.libpath field in my job.properties file to point to the directory in which the jar resides.
I searched for other possible versions of Spark in the classpath section in the stdout log, and found two instances where spark-1.3.0-cdh5.4.5-yarn-shuffle.jar was being picked up (fortunately, spark-assembly-1.5.2-hadoop2.6.0.jar is being picked up elsewhere too so I am setting the path correctly).
So, the problem seems to be that oozie, or oozie launcher is defaulting to use spark 1.3 for some reason (which is installed on the system that the job is trying to run on). I tried setting the oozie.use.system.libpath field to false in the job.properties file, but it doesn't seem to have helped. Any ideas on what I can to do prevent spark 1.3 from being picked up, or any other solutions that can solve the NoSuchMethodError I am facing?
Any help would be greatly appreciated, thanks.

HDFS delete command results in: ArrayIndexOutOfBoundsException and "RemoteException in offerService"

I notice that HDFS delete commands will randomly fail. For example, in a MapReduce job I delete a directory at startup. Occasionally it fails with the error below, but will succeed on the second try.
org.apache.hadoop.ipc.RemoteException(java.lang.ArrayIndexOutOfBoundsException): java.lang.ArrayIndexOutOfBoundsException
at org.apache.hadoop.ipc.Client.call(Client.java:1364)
at org.apache.hadoop.ipc.Client.call(Client.java:1411)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:206)
at com.sun.proxy.$Proxy14.delete(Unknown Source)
at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.delete(ClientNamenodeProtocolTranslatorPB.java:513)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
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.$Proxy15.delete(Unknown Source)
at org.apache.hadoop.hdfs.DFSClient.delete(DFSClient.java:1862)
at org.apache.hadoop.hdfs.DistributedFileSystem$11.doCall(DistributedFileSystem.java:599)
at org.apache.hadoop.hdfs.DistributedFileSystem$11.doCall(DistributedFileSystem.java:595)
at org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)
at org.apache.hadoop.hdfs.DistributedFileSystem.delete(DistributedFileSystem.java:595)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.util.RunJar.main(RunJar.java:212)
Digging into the datanode logs I see this exception:
RemoteException in offerService
org.apache.hadoop.ipc.RemoteException(java.lang.NullPointerException): java.lang.NullPointerException
at org.apache.hadoop.ipc.Client.call(Client.java:1411)
at org.apache.hadoop.ipc.Client.call(Client.java:1364)
at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:206)
at com.sun.proxy.$Proxy17.blockReport(Unknown Source)
at org.apache.hadoop.hdfs.protocolPB.DatanodeProtocolClientSideTranslatorPB.blockReport(DatanodeProtocolClientSideTranslatorPB.java:175)
at org.apache.hadoop.hdfs.server.datanode.BPServiceActor.blockReport(BPServiceActor.java:493)
at org.apache.hadoop.hdfs.server.datanode.BPServiceActor.offerService(BPServiceActor.java:716)
at org.apache.hadoop.hdfs.server.datanode.BPServiceActor.run(BPServiceActor.java:851)
at java.lang.Thread.run(Thread.java:745)
I can't find any help on that, and I'm not sure where else to look. Does anyone know what that issue is?
I'm running Ubuntu 14.04.1 LTS and hadoop version prints out:
Hadoop 2.5.0-cdh5.3.1
Subversion http://github.com/cloudera/hadoop -r 4cda8416c73034b59cc8baafbe3666b074472846
Compiled by jenkins on 2015-01-28T00:41Z
Compiled with protoc 2.5.0
From source with checksum 6a018149a764de4b8992755df9a2a1b
This command was run using /opt/cloudera/parcels/CDH-5.3.1-1.cdh5.3.1.p0.5/jars/hadoop-common-2.5.0-cdh5.3.1.jar
Thanks for your help!
I haven't tried it yet, but Cloudera suggested upgrading to 5.3.3:
http://community.cloudera.com/t5/Storage-Random-Access-HDFS/HDFS-delete-command-results-in-ArrayIndexOutOfBoundsException/m-p/31817#U31817

NoSuchMethodError using Guava 15 on Hadoop (2.3.0)

I have a compiled jar for Hadoop including this library:
com.google.guava:guava:jar:15.0:compile
When I submit it into my Hadoop CDH5.0.1 cluster I have this error:
java.lang.NoSuchMethodError: com.google.common.base.Stopwatch.createStarted()Lcom/google/common/base/Stopwatch;
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.util.ProgramDriver$ProgramDescription.invoke(ProgramDriver.java:72)
at org.apache.hadoop.util.ProgramDriver.run(ProgramDriver.java:144)
at org.apache.hadoop.util.ProgramDriver.driver(ProgramDriver.java:152)
at com.trovit.pipeline.AdsPipelineDriver.main(AdsPipelineDriver.java:17)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.util.RunJar.main(RunJar.java:212)
The main thing is that Hadoop has an older version of guava into its classpath, loads it before mine and crashes because the used function doesn't exist.
I've tried configuration parameters such as mapreduce.task.classpath.user.precedence, mapreduce.task.classpath.first or mapreduce.job.user.classpath.first but none of them worked.
Any guess for solving this problem?

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