1. Hadoop中的NullWritable

NullWritable是Writable的一个特殊类，实现方法为空实现，不从数据流中读数据，也不写入数据，只充当占位符，如在MapReduce中，如果你不需要使用键或值，你就可以将键或值声明为NullWritable,NullWritable是一个不可变的单实例类型。

比如，我设置map的输出为，这样做：

 @Override

 protected void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {

 String line = value.toString();

 WebLogBean webLogBean = WebLogParser.parser(line);

 WebLogParser.filtStaticResource(webLogBean, pages); // 过滤js/图片/css等静态资源

 k.set(webLogBean.toString());

 context.write(k, NullWritable.get(););

 }

不能使用new NullWritable()来定义，获取空值只能NullWritable.get()来获取

来自https://www.cnblogs.com/Skyar/p/5815486.html

2. Yarn上的各种Id

  • jobId

描述：出自MapReduce，对作业的唯一标识。
格式：job_${clusterStartTime}_${jobid}
例子：job_1498552288473_2742

  • applicationId

描述：在yarn中对作业的唯一标识。
格式：application_${clusterStartTime}_${applicationId}
例子：application_1498552288473_2742

  • taskId

描述：作业中的任务的唯一标识
格式：task_${clusterStartTime}_${applicationId}_[m|r]_${taskId}
例子：task_1498552288473_2742_m_000000、task_1498552288473_2742_r_000000

  • attempId

描述：任务尝试执行的一次id
格式：attempt_${clusterStartTime}_${applicationId}_[m|r]_${taskId}_${attempId}
例子：attempt_1498552288473_2742_m_000000_0

  • appAttempId

描述：ApplicationMaster的尝试执行的一次id。
格式：appattempt_${clusterStartTime}_${applicationId}_${appAttempId}
例子：appattempt_1498552288473_2742_000001

  • containerId

描述：container的id
格式：container_e*epoch*_${clusterStartTime}_${applicationId}_${appAttempId}_${containerId}
例子：container_e20_1498552288473_2742_01_000032、container_1498552288473_2742_01_000032

参考：Yarn之日志分析

3. Yarn的运行日志存放目录以及备份目录

Yarn上任务的运行日志存在哪呢？你有没有疑问过，今天终于明白了，以Flink on yarn上的任务为例(其他任务类似，不一定完全相同)，看JobManager.log的截图

 2019-08-05 09:51:55,826 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         - --------------------------------------------------------------------------------

 2019-08-05 09:51:55,827 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -  Starting YarnSessionClusterEntrypoint (Version: 1.7.1, Rev:<unknown>, Date:<unknown>)

 2019-08-05 09:51:55,827 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -  OS current user: yarn

 2019-08-05 09:51:56,255 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -  Current Hadoop/Kerberos user: worker

 2019-08-05 09:51:56,255 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -  JVM: Java HotSpot(TM) 64-Bit Server VM - Oracle Corporation - 1.8/25.65-b01

 2019-08-05 09:51:56,255 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -  Maximum heap size: 1388 MiBytes

 2019-08-05 09:51:56,255 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -  JAVA_HOME: /usr/local/jdk/

 2019-08-05 09:51:56,258 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -  Hadoop version: 2.6.0-cdh5.5.0

 2019-08-05 09:51:56,258 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -  JVM Options:

 2019-08-05 09:51:56,258 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -     -Xmx1448m

 2019-08-05 09:51:56,258 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -     -Dlog.file=/var/log/hadoop/container/application_1564969910131_0252/container_e05_1564969910131_0252_01_000001/jobmanager.log

 2019-08-05 09:51:56,258 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -     -Dlogback.configurationFile=file:logback.xml

 2019-08-05 09:51:56,258 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -     -Dlog4j.configuration=file:log4j.properties

 2019-08-05 09:51:56,258 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -  Program Arguments: (none)

 2019-08-05 09:51:56,259 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         -  Classpath: lib/flink-python_2.11-1.7.1.jar:lib/flink-shaded-hadoop2-uber-1.7.1.jar:lib/log4j-1.2.17.jar:lib/slf4j-log4j12-1.7.15.jar:log4j.properties:logback.xml:flink.jar:flink-conf.yaml::/etc/hadoop/conf.cloudera.yarn4:/run/cloudera-scm-agent/process/47188-yarn-NODEMANAGER:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-annotations.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-auth.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-aws.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-common-tests.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-common.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-nfs.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-nfs-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-common-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-common-2.6.0-cdh5.5.0-tests.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-aws-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-auth-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/hadoop-annotations-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-format.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-format-sources.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-format-javadoc.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-tools.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-thrift.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-test-hadoop2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-scrooge_2.10.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-scala_2.10.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-protobuf.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-pig.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-pig-bundle.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-jackson.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-hadoop.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-hadoop-bundle.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-generator.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-encoding.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-common.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-column.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-cascading.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/parquet-avro.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/hue-plugins-3.9.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-httpclient-3.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-math3-3.1.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-digester-1.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/curator-recipes-2.7.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-net-3.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-configuration-1.6.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/httpclient-4.2.5.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/gson-2.2.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-el-1.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jackson-xc-1.8.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/httpcore-4.2.5.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/curator-framework-2.7.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jersey-core-1.9.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jaxb-impl-2.2.3-1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jasper-compiler-5.5.23.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/htrace-core4-4.0.1-incubating.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-lang-2.6.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jsp-api-2.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jetty-util-6.1.26.cloudera.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jets3t-0.9.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jaxb-api-2.2.2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jackson-mapper-asl-1.8.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/hamcrest-core-1.3.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-logging-1.1.3.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/apacheds-i18n-2.0.0-M15.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/zookeeper.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/avro.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/stax-api-1.0-2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/protobuf-java-2.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/mockito-all-1.8.5.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/log4j-1.2.17.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jsr305-3.0.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jetty-6.1.26.cloudera.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jersey-server-1.9.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/java-xmlbuilder-0.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jackson-jaxrs-1.8.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/guava-11.0.2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-io-2.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/xmlenc-0.52.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/snappy-java-1.0.4.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/servlet-api-2.5.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/paranamer-2.3.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-compress-1.4.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-collections-3.2.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-codec-1.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-cli-1.2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-beanutils-core-1.8.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/commons-beanutils-1.7.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/aws-java-sdk-1.7.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/asm-3.2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/api-util-1.0.0-M20.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/api-asn1-api-1.0.0-M20.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/apacheds-kerberos-codec-2.0.0-M15.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/activation-1.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/slf4j-log4j12.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/xz-1.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/slf4j-api-1.7.5.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/netty-3.6.2.Final.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/logredactor-1.0.3.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/junit-4.11.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jsch-0.1.42.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jettison-1.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jersey-json-1.9.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jasper-runtime-5.5.23.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/jackson-core-asl-1.8.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop/lib/curator-client-2.7.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/hadoop-hdfs-nfs.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/hadoop-hdfs-tests.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/hadoop-hdfs.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/hadoop-hdfs-nfs-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/hadoop-hdfs-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/hadoop-hdfs-2.6.0-cdh5.5.0-tests.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/xmlenc-0.52.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/xml-apis-1.3.04.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/xercesImpl-2.9.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/servlet-api-2.5.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/protobuf-java-2.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/netty-3.6.2.Final.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/log4j-1.2.17.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/leveldbjni-all-1.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/jsr305-3.0.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/jsp-api-2.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/jetty-util-6.1.26.cloudera.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/jetty-6.1.26.cloudera.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/jersey-server-1.9.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/jersey-core-1.9.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/jasper-runtime-5.5.23.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/jackson-mapper-asl-1.8.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/jackson-core-asl-1.8.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/htrace-core4-4.0.1-incubating.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/guava-11.0.2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/commons-logging-1.1.3.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/commons-lang-2.6.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/commons-io-2.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/commons-el-1.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/commons-daemon-1.0.13.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/commons-codec-1.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/commons-cli-1.2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-hdfs/lib/asm-3.2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-api.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-applications-distributedshell.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-applications-unmanaged-am-launcher.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-client.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-common.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-registry.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-applicationhistoryservice.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-common.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-nodemanager.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-resourcemanager.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-tests.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-web-proxy.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-web-proxy-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-tests-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-resourcemanager-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-nodemanager-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-common-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-server-applicationhistoryservice-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-registry-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-common-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-client-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-applications-unmanaged-am-launcher-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-applications-distributedshell-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/hadoop-yarn-api-2.6.0-cdh5.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/spark-yarn-shuffle.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/xz-1.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/servlet-api-2.5.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/protobuf-java-2.5.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/log4j-1.2.17.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/leveldbjni-all-1.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jsr305-3.0.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jline-2.11.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jetty-util-6.1.26.cloudera.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jetty-6.1.26.cloudera.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jettison-1.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jersey-server-1.9.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jersey-json-1.9.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jersey-guice-1.9.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jersey-core-1.9.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jersey-client-1.9.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jaxb-impl-2.2.3-1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jaxb-api-2.2.2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/javax.inject-1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jackson-xc-1.8.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jackson-mapper-asl-1.8.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jackson-jaxrs-1.8.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/jackson-core-asl-1.8.8.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/guice-servlet-3.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/guice-3.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/guava-11.0.2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/commons-logging-1.1.3.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/commons-lang-2.6.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/commons-io-2.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/commons-httpclient-3.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/commons-compress-1.4.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/commons-collections-3.2.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/commons-codec-1.4.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/commons-cli-1.2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/asm-3.2.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/aopalliance-1.0.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/activation-1.1.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/zookeeper.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/spark-1.5.0-cdh5.5.0-yarn-shuffle.jar:/opt/cloudera/parcels/CDH-5.5.0-1.cdh5.5.0.p0.8/lib/hadoop-yarn/lib/stax-api-1.0-2.jar

 2019-08-05 09:51:56,260 INFO  org.apache.flink.runtime.entrypoint.ClusterEntrypoint         - --------------------------------------------------------------------------------

看见了吧，去JobManager那台机器上对应目录下去找，可以看到日志所在文件夹

 总用量 16K

 drwx--x---  3 yarn yarn   63 7月  25 17:58 application_1564048714696_0300

 drwx--x---  3 yarn yarn   63 7月  28 13:39 application_1564110901389_0235

 drwx--x---  4 yarn yarn  116 8月   5 09:52 application_1564969910131_0252

 drwx--x---  3 yarn yarn   63 8月   5 20:35 application_1564998210570_0394

这个是运行时日志，如果任务停止了呢，Yarn一般会有备份的，比如我这边用的Cloudera，有个配置

然后你用

 hadoop fs -ls /tmp/logs/用户名/logs

发现日志都在。

4. Hadoop中的主要配置文件

core-site.xml：hadoop全局配置：HDFS路径 ，临时数据的公共目录，ZooKeeper集群的地址和端口。

<configuration>

    <property>

        <name>hadoop.tmp.dir</name>

        <value>/usr/local/data/hadoop/tmp</value>

        <!-- 其他临时目录的父目录 -->

    </property>

    <property>

        <name>fs.defaultFS</name>

        <value>hdfs://hadoop-alone:9000</value>

        <!--

            hdfs://host:port/

            默认的文件系统的名称。通常指定namenode的URI地址，包括主机和端口

        -->

    </property>

    <property>

        <name>io.file.buffer.size</name>

        <value>4096</value>

        <!--

            在序列文件中使用的缓冲区大小，这个缓冲区的大小应该是页大小（英特尔x86上为4096）的倍数

            他决定读写操作中缓冲了多少数据（单位kb）

        -->

    </property>

    <!--ZooKeeper集群的地址和端口。注意，数量一定是奇数，且不少于三个节点-->

    <property>

        <name>ha.zookeeper.quorum</name>

        <value>hadoop1:2181,hadoop2:2181,hadoop3:2181,hadoop4:2181,hadoop5:2181</value>

    </property>

</configuration>

hdfs-site.xml：HDFS文件系统属性：dfs.replication（文件块的数据备份数）， dfs.data.dir（datanode节点存储在文件系统的目录） ， dfs.name.dir（namenode节点存储在文件系统的目录） 。

<configuration>

    <property>

        <name>dfs.replication</name>

        <value>3</value>

        <!--指定dataNode存储block的副本数量，默认值是3个，该值应该不大于4-->

    </property>

    <property>

        <name>dfs.blocksize</name>

        <value>268435456</value>

        <!--大型的文件系统HDFS块大小为256MB，先默认是128MB-->

    </property>

    <property>

        <name>dfs.namenode.name.dir</name>

        <value>file://${hadoop.tmp.dir}/dfs/name</value>

        <!--

            存放namenode的名称表（fsimage）的目录，如果这是一个逗号分隔的目录列表，

            那么在所有目录中复制名称表，用于冗余。

         -->

    </property>

    <property>

        <name>dfs.datanode.data.dir</name>

        <value>file://${hadoop.tmp.dir}/dfs/data</value>

        <!--

            存放datanode块的目录。如果这是一个逗号分隔的目录列表，

            那么数据将存储在所有命名的目录中，通常存储在不同的设备上。

        -->

    </property>

    <property>

        <name>dfs.namenode.http-address</name>

        <value>0.0.0.0:50070</value>

        <!---->

    </property>

    <property>

        <name>dfs.namenode.secondary.http-address</name>

        <value>0.0.0.0:50090</value>

        <!--secondary namenode HTTP服务器地址和端口。-->

    </property>

    <property>

        <name>dfs.permissions</name>

        <value>false</value>

    </property>

    <property>

        <name>dfs.permissions.enabled</name>

        <value>false</value>

        <!-- 当为true时，则允许HDFS的检测，当为false时，则关闭HDFS的检测，但不影响其它HDFS的其它功能。-->

    </property>

    <property>

        <name>dfs.nameservices</name>

        <value>hadoop-cluster1</value>

        <!--给hdfs集群起名字 -->

    </property>

    <property>

        <name>dfs.namenode.handler.count</name>

        <value>100</value>

        <!-- RPC服务器的监听client线程数，如果dfs.namenode.servicerpc-address属性没有配置，则线程会监听所有节点的请求。-->

    </property>

</configuration>

yarn-site.xml：设置Yarn的参数，NodeManager、ResourceManager等

<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>

    <property>

        <name>yarn.resourcemanager.admin.address</name>

        <value>hadoop-alone:8033</value>

    </property>

    <property>

        <name>yarn.resourcemanager.resource-tracker.address</name>

        <value>hadoop-alone:8025</value>

    </property>

    <property>

        <name>yarn.resourcemanager.scheduler.address</name>

        <value>hadoop-alone:8030</value>

    </property>

    <property>

        <name>yarn.resourcemanager.address</name>

        <value>hadoop-alone:8050</value>

    </property>

    <property>

        <name>yarn.resourcemanager.scheduler.address</name>

        <value>hadoop-alone:8030</value>

    </property>

</configuration>

mapred-site.xml：指明MapReduce的运行框架为YARN；

<configuration>

    <property>

        <name>mapreduce.framework.name</name>

        <value>yarn</value>

        <!--执行框架设置为 Hadoop YARN.-->

    </property>

</configuration>

hadoop-env.sh：设置jdk的安装路径

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