Cloudera Manager介绍

    Cloudera Manager(简称CM)是Cloudera公司开发的一款大数据集群安装部署利器，这款利器具有集群自动化安装、中心化管理、集群监控、报警等功能，使得安装集群从几天的时间缩短在几小时以内，运维人员从数十人降低到几人以内，极大的提高集群管理的效率。

CM技术架构

　　Agent：安装在每台主机上。该代理负责启动和停止的过程，拆包配置，触发装置和监控主机。
　　Management Service：由一组执行各种监控，警报和报告功能角色的服务。
　　Database：存储配置和监视信息。通常情况下，多个逻辑数据库在一个或多个数据库服务器上运行。例如，Cloudera的管理服务器和监控角色使用不同的逻辑数据库。
　　Cloudera Repository：软件由Cloudera 管理分布存储库。
　　Clients：是用于与服务器进行交互的接口：
　　Admin Console ：基于Web的用户界面与管理员管理集群和Cloudera管理。
　　API ：与开发人员创建自定义的Cloudera Manager应用程序的API。

CM四大功能

　　管理：对集群进行管理，如添加、删除节点等操作。
　　监控：监控集群的健康情况，对设置的各种指标和系统运行情况进行全面监控。
　　诊断：对集群出现的问题进行诊断，对出现的问题给出建议解决方案。
　　集成：对hadoop的多组件进行整合。

需要安装的组件

Cloudera Manager

CDH

JDK

Mysql（主节点）  + JDBC

需要注意的是CDH的版本需要等于或者小于CM的版本

相关的设置

主机名和hosts文件

关闭防火墙

ssh无密码登陆

配置NTP服务

关闭SElinux状态

配置集群

配置数据库

一些安装过程

主节点安装cloudera manager

把我们下载好的cloudera-manager-*.tar.gz包和mysql驱动包mysql-connector-java-*-bin.jar放到主节点cm0的/opt中。

Cloudera Manager建立数据库 

使用命令 cp mysql-connector-java-5.1.40-bin.jar   /opt/cm-5.8.2/share/cmf/lib/ 把mysql-connector-java-5.1.40-bin.jar放到/opt/cm-5.8.2/share/cmf/lib/中。

使用命令 /opt/cm-5.8.2/share/cmf/schema/scm_prepare_database.sh mysql cm  -h cm0  -u  root  -p  123456  --scm-host  cm0  scm scm scm  在主节点初始化CM5的数据库。

实际位置：/usr/share/cmf/schema/scm_prepare_database.sh

Agent配置 

使用命令 vim  /opt/cm-5.8.2/etc/cloudera-scm-agent/config.ini 主节点修改agent配置文件。

在主节点cm0用命令 scp -r   /opt/cm-5.8.2     root@cm1:/opt/ 同步Agent到其他所有节点。

实际位置：/etc/cloudera-scm-agent/config.ini

在所有节点创建cloudera-scm用户

使用命令 useradd --system --home=/opt/cm-5.8.2/run/cloudera-scm-server/  --no-create-home  --shell=/bin/false --comment "Cloudera SCM User" cloudera-scm

启动cm和agent 

主节点cm0通过命令 /opt/cm-5.8.2/etc/init.d/cloudera-scm-server start 启动服务端。

所有节点通过命令 /opt/cm-5.8.2/etc/init.d/cloudera-scm-agent start 启动Agent服务。（所有节点都要启动Agent服务，包括服务端）

Cloudera Manager Server和Agent都启动以后，就可以进行尝试访问了。http://master:7180/cmf/login

实际位置：/etc/rc.d/init.d/cloudera-scm-server 和 /etc/rc.d/init.d/cloudera-scm-agent

补充：/etc/init.d 是 /etc/rc.d/init.d 的软链接(soft link)。/etc/init.d里的shell脚本能够响应start，stop，restart，reload命令来管理某个具体的应用。比如经常看到的命令： /etc/init.d/networking start 这些脚本也可被其他trigger直接激活执行，这些trigger被软连接在/etc/rcN.d/中。这些原理似乎可以用来写daemon程序，让某些程序在开关机时运行。

CDH的安装和集群配置

新建目录为 /opt/cloudera/parcel-repo ，把之前下载的安装文件放到主节点的这个目录下。

安装parcel，安装过程中有什么问题，可以用 /opt/cm-5.8.2/etc/init.d/cloudera-scm-agent status ， /opt/cm-5.8.2/etc/init.d/cloudera-scm-server status 查看服务器客户端状态。

也可以通过 /var/log/cloudera-scm-server/cloudera-scm-server.log ， /var/log/cloudera-scm-agent/cloudera-scm-agent.log 查看日志。

如果上面的路径找不到则在日志文件夹＂/opt/cm-5.8.2/log＂查看日志，里面包含server和agent的log，使用命令如下:

tail -f /opt/cm-5.8.2/log/cloudera-scm-server/cloudera-scm-server.log

tail -f /opt/cm-5.8.2/log/cloudera-scm-agent/cloudera-scm-agent.log

实际位置： /var/log/cloudera-scm-server/cloudera-scm-server.log 和 /var/log/cloudera-scm-agent/cloudera-scm-agent.log

遇到的一些问题

问题一：

[root@node1 ~]# spark-shell
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/fs/FSDataInputStream
        at org.apache.spark.deploy.SparkSubmitArguments$$anonfun$mergeDefaultSparkProperties$.apply(SparkSubmitArguments.scala:)
        at org.apache.spark.deploy.SparkSubmitArguments$$anonfun$mergeDefaultSparkProperties$.apply(SparkSubmitArguments.scala:)
        at scala.Option.getOrElse(Option.scala:)
        at org.apache.spark.deploy.SparkSubmitArguments.mergeDefaultSparkProperties(SparkSubmitArguments.scala:)
        at org.apache.spark.deploy.SparkSubmitArguments.<init>(SparkSubmitArguments.scala:)
        at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:)
        at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
Caused by: java.lang.ClassNotFoundException: org.apache.hadoop.fs.FSDataInputStream
        at java.net.URLClassLoader.findClass(URLClassLoader.java:)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:)
        ...  more

查找spark-env.sh文件的位置：

[root@node1 /]# find / -name spark-env.sh
’: No such file or directory
/run/cloudera-scm-agent/process/-spark2_on_yarn-SPARK2_YARN_HISTORY_SERVER/aux/client/spark-env.sh
/run/cloudera-scm-agent/process/-spark2_on_yarn-SPARK2_YARN_HISTORY_SERVER/spark2-conf/spark-env.sh
……
/run/cloudera-scm-agent/process/-spark_on_yarn-SPARK_YARN_HISTORY_SERVER-SparkUploadJarCommand/aux/client/spark-env.sh
/run/cloudera-scm-agent/process/-spark_on_yarn-SPARK_YARN_HISTORY_SERVER-SparkUploadJarCommand/spark-conf/spark-env.sh
/gvfs’: Permission denied
/etc/spark/conf.cloudera.spark_on_yarn/spark-env.sh
/etc/spark2/conf.cloudera.spark2_on_yarn/spark-env.sh
/opt/cloudera/parcels/CDH--.cdh5./etc/spark/conf.dist/spark-env.sh

打开 /etc/spark2/conf.cloudera.spark2_on_yarn/spark-env.sh ，查看到一些内容：

export SPARK_HOME=/opt/cloudera/parcels/SPARK2-.cloudera4-.cdh5./lib/spark2

export HADOOP_HOME=/opt/cloudera/parcels/CDH--.cdh5./lib/hadoop

export SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:$(paste -sd: "$SELF/classpath.txt")"

并在文件的最后追加内容：

export SPARK_DIST_CLASSPATH=$(hadoop classpath)

问题没有解决！

打开 /opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/etc/spark/conf.dist/spark-env.sh ，查看到一些内容：

export STANDALONE_SPARK_MASTER_HOST=`hostname`
export SPARK_MASTER_IP=$STANDALONE_SPARK_MASTER_HOST
export SPARK_MASTER_PORT=
export SPARK_WORKER_PORT=
export SPARK_WORKER_DIR=/var/run/spark/work
export SPARK_LOG_DIR=/var/log/spark
export SPARK_PID_DIR='/var/run/spark/'
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:$SPARK_LIBRARY_PATH/spark-assembly.jar"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/hadoop/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/hadoop/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/hadoop-hdfs/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/hadoop-hdfs/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/hadoop-mapreduce/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/hadoop-mapreduce/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/hadoop-yarn/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/hadoop-yarn/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/hive/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/flume-ng/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/parquet/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/usr/lib/avro/*"
在 /etc/spark2/conf.cloudera.spark2_on_yarn/spark-env.sh 文件的末尾追加以下内容：
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/spark/lib/spark-assembly.jar"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-hdfs/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-hdfs/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-mapreduce/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-mapreduce/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-yarn/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-yarn/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hive/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/flume-ng/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/parquet/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/avro/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/jars/*"
export SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/jars/*"

问题依然没有解决！

在 /opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/etc/spark/conf.dist/spark-env.sh 文件的末尾追加以下内容：

SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/spark/lib/spark-assembly.jar"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-hdfs/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-hdfs/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-mapreduce/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-mapreduce/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-yarn/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hadoop-yarn/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/hive/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/flume-ng/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/parquet/lib/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/lib/avro/*"
SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/jars/*"
export SPARK_DIST_CLASSPATH="$SPARK_DIST_CLASSPATH:/opt/cloudera/parcels/CDH-5.14.2-1.cdh5.14.2.p0.3/jars/*"
问题解决！执行命令 spark-shell ，返回信息如下：
[root@node1 ~]# spark-shell
Setting default log level to "WARN".
To adjust logging level use sc.setLogLevel(newLevel).
SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding -.cdh5./jars/slf4j-log4j12-.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding -.cdh5./jars/avro-tools--cdh5.14.2.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding -.cdh5./jars/pig--cdh5.14.2.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding -.cdh5./jars/slf4j-simple-.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
SLF4J: Actual binding is of type [org.slf4j.impl.Log4jLoggerFactory]
Welcome to
      ____              __
     / __/__  ___ _____/ /__
    _\ \/ _ \/ _ `/ __/  '_/
   /___/ .__/\_,_/_/ /_/\_\   version
      /_/

Using Scala version  (Java HotSpot(TM) -Bit Server VM, Java 1.8.0_131)
Type in expressions to have them evaluated.
Type :help for more information.
Spark context available as sc (master = local[*], app ).
// :: WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
SQL context available as sqlContext.

scala>
执行Spark自带的案例程序：
spark-submit --class org.apache.spark.examples.SparkPi --executor-memory 500m --total-executor-cores  /opt/cloudera/parcels/SPARK2-.cloudera4-.cdh5./lib/spark2/examples/jars/spark-examples_2.-.cloudera4.jar

返回信息如下：

[root@node1 ~]# spark-submit --class org.apache.spark.examples.SparkPi --executor-memory 500m --total-executor-cores  /opt/cloudera/parcels/SPARK2-.cloudera4-.cdh5./lib/spark2/examples/jars/spark-examples_2.-.cloudera4.jar
SLF4J: Class path contains multiple SLF4J bindings.
……
// :: INFO Remoting: Remoting started; listening on addresses :[akka.tcp://sparkDriverActorSystem@10.200.101.131:38370]
// :: INFO ui.SparkUI: Started SparkUI at http://10.200.101.131:4040
// :: INFO spark.SparkContext: Added JAR .cloudera4-.cdh5./lib/spark2/examples/jars/spark-examples_2.-.cloudera4.jar at spark://10.200.101.131:37025/jars/spark-examples_2.11-2.1.0.cloudera4.jar with timestamp 1556186427964
// :: INFO scheduler.DAGScheduler: Got job  (reduce at SparkPi.scala:) with  output partitions
// :: INFO scheduler.DAGScheduler: Final stage: ResultStage  (reduce at SparkPi.scala:)
// :: INFO executor.Executor: Fetching spark://10.200.101.131:37025/jars/spark-examples_2.11-2.1.0.cloudera4.jar with timestamp 1556186427964
// :: INFO util.Utils: Fetching spark://10.200.101.131:37025/jars/spark-examples_2.11-2.1.0.cloudera4.jar to /tmp/spark-c8bb0344-ce1a-4acc-98d8-dfdebd6b95d6/userFiles-c39c4a70-c9b0-40f7-b48f-cf0f4d46042e/fetchFileTemp8308576688554785370.tmp
// :: INFO executor.Executor: Adding -.cloudera4.jar to class loader
……
Pi is roughly 3.134555672778364
……
// :: INFO ui.SparkUI: Stopped Spark web UI at http://10.200.101.131:4040
// :: INFO spark.MapOutputTrackerMasterEndpoint: MapOutputTrackerMasterEndpoint stopped!
// :: INFO storage.MemoryStore: MemoryStore cleared
// :: INFO storage.BlockManager: BlockManager stopped
// :: INFO storage.BlockManagerMaster: BlockManagerMaster stopped
// :: INFO scheduler.OutputCommitCoordinator$OutputCommitCoordinatorEndpoint: OutputCommitCoordinator stopped!
// :: INFO spark.SparkContext: Successfully stopped SparkContext
// :: INFO util.ShutdownHookManager: Shutdown hook called
// :: INFO util.ShutdownHookManager: Deleting directory /tmp/spark-c8bb0344-ce1a-4acc-98d8-dfdebd6b95d6

从上面的信息可以看出，案例程序的运算结果为“Pi is roughly 3.134555672778364”

参考：

https://www.jianshu.com/p/1ed522c1ad1e

https://www.cnblogs.com/felixzh/p/9082344.html

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