Flume 1.7.0安装与实例

Flume安装

系统要求：
需安装JDK 1.7及以上版本

1、 下载二进制包
下载页面：http://flume.apache.org/download.html
1.7.0下载地址：http://www.apache.org/dyn/closer.lua/flume/1.7.0/apache-flume-1.7.0-bin.tar.gz

2、解压

$ cp ~/Downloads/apache-flume-1.7.0-bin.tar.gz ~$ cd $ tar -zxvf apache-flume-1.7.0-bin.tar.gz$ cd apache-flume-1.7.0-bin

3、创建flume-env.sh文件

$ cp conf/flume-env.sh.template conf/flume-env.sh

简单实例－传输指定文件

场景：两台机器，一台为client，一台为agent，在client上将指定文件传输到agent机器上。

1、创建配置文件

根据flume自身提供的模板，创建flume.conf配置文件。

$ cp conf/flume-conf.properties.template conf/flume.conf

编辑文件flume.conf：

$ vi conf/flume.conf

在文件末尾加入以下配置：

# Define a memory channel called ch1 on agent1agent1.channels.ch1.type = memory# Define an Avro source called avro-source1 on agent1 and tell it# to bind to 0.0.0.0:41414. Connect it to channel ch1.agent1.sources.avro-source1.channels = ch1agent1.sources.avro-source1.type = avroagent1.sources.avro-source1.bind = 0.0.0.0agent1.sources.avro-source1.port = 41414# Define a logger sink that simply logs all events it receives# and connect it to the other end of the same channel.agent1.sinks.log-sink1.channel = ch1agent1.sinks.log-sink1.type = logger# Finally, now that we've defined all of our components, tell# agent1 which ones we want to activate.agent1.channels = ch1agent1.sources = avro-source1agent1.sinks = log-sink1

保存，并且退出：

2、启动flume server
在作为agent的机器上执行以下：

bin/flume-ng agent --conf ./conf/ -f conf/flume.conf -Dflume.root.logger=DEBUG,console -n agent1

3、在新的窗口开启client
在作为client的机器上执行以下：
（由于当前环境是在单机上模拟两台机器，所以，直接在新的终端中输入以下命令）

$ bin/flume-ng avro-client --conf conf -H localhost -p 41414 -F /etc/passwd -Dflume.root.logger=DEBUG,console

4、结果
这个时候，你可以看到以下消息：

2012-03-16 16:39:17,124 (main) [DEBUG - org.apache.flume.client.avro.AvroCLIClient.run(AvroCLIClient.java:175)] Finished2012-03-16 16:39:17,127 (main) [DEBUG - org.apache.flume.client.avro.AvroCLIClient.run(AvroCLIClient.java:178)] Closing reader2012-03-16 16:39:17,127 (main) [DEBUG - org.apache.flume.client.avro.AvroCLIClient.run(AvroCLIClient.java:183)] Closing transceiver2012-03-16 16:39:17,129 (main) [DEBUG - org.apache.flume.client.avro.AvroCLIClient.main(AvroCLIClient.java:73)] Exiting

在前面那个开启flume server的窗口，可以看到如下消息：

2012-03-16 16:39:16,738 (New I/O server boss #1 ([id: 0x49e808ca, /0:0:0:0:0:0:0:0:41414])) [INFO - org.apache.avro.ipc.NettyServer$NettyServerAvroHandler.handleUpstream(NettyServer.java:123)] [id: 0x0b92a848, /127.0.0.1:39577 => /127.0.0.1:41414] OPEN2012-03-16 16:39:16,742 (New I/O server worker #1-1) [INFO - org.apache.avro.ipc.NettyServer$NettyServerAvroHandler.handleUpstream(NettyServer.java:123)] [id: 0x0b92a848, /127.0.0.1:39577 => /127.0.0.1:41414] BOUND: /127.0.0.1:414142012-03-16 16:39:16,742 (New I/O server worker #1-1) [INFO - org.apache.avro.ipc.NettyServer$NettyServerAvroHandler.handleUpstream(NettyServer.java:123)] [id: 0x0b92a848, /127.0.0.1:39577 => /127.0.0.1:41414] CONNECTED: /127.0.0.1:395772012-03-16 16:39:17,129 (New I/O server worker #1-1) [INFO - org.apache.avro.ipc.NettyServer$NettyServerAvroHandler.handleUpstream(NettyServer.java:123)] [id: 0x0b92a848, /127.0.0.1:39577 :> /127.0.0.1:41414] DISCONNECTED2012-03-16 16:39:17,129 (New I/O server worker #1-1) [INFO - org.apache.avro.ipc.NettyServer$NettyServerAvroHandler.handleUpstream(NettyServer.java:123)] [id: 0x0b92a848, /127.0.0.1:39577 :> /127.0.0.1:41414] UNBOUND2012-03-16 16:39:17,129 (New I/O server worker #1-1) [INFO - org.apache.avro.ipc.NettyServer$NettyServerAvroHandler.handleUpstream(NettyServer.java:123)] [id: 0x0b92a848, /127.0.0.1:39577 :> /127.0.0.1:41414] CLOSED2012-03-16 16:39:17,302 (Thread-1) [INFO - org.apache.flume.sink.LoggerSink.process(LoggerSink.java:68)] Event: { headers:{} body:[B@5c1ae90c }2012-03-16 16:39:17,302 (Thread-1) [INFO - org.apache.flume.sink.LoggerSink.process(LoggerSink.java:68)] Event: { headers:{} body:[B@6aba4211 }2012-03-16 16:39:17,302 (Thread-1) [INFO - org.apache.flume.sink.LoggerSink.process(LoggerSink.java:68)] Event: { headers:{} body:[B@6a47a0d4 }2012-03-16 16:39:17,302 (Thread-1) [INFO - org.apache.flume.sink.LoggerSink.process(LoggerSink.java:68)] Event: { headers:{} body:[B@48ff4cf }...

简单实例－将目录文件上传到HDFS

场景：将机器上的某个文件夹下的文件上传到HDFS上。

1、配置conf/flume.conf

# Define a memory channel called ch1 on agent1agent1.channels.ch1.type = memory# Define an Avro source called avro-source1 on agent1 and tell it# to bind to 0.0.0.0:41414. Connect it to channel ch1.agent1.sources.spooldir-source1.channels = ch1agent1.sources.spooldir-source1.type = spooldiragent1.sources.spooldir-source1.spoolDir=/home/hadoop/flume-1.7.0/tmpDataagent1.sources.spooldir-source1.bind = 0.0.0.0agent1.sources.spooldir-source1.port = 41414# Define a logger sink that simply logs all events it receives# and connect it to the other end of the same channel.agent1.sinks.hdfs-sink1.channel = ch1agent1.sinks.hdfs-sink1.type = hdfsagent1.sinks.hdfs-sink1.hdfs.path = hdfs://master:9000/testagent1.sinks.hdfs-sink1.hdfs.filePrefix = events-agent1.sinks.hdfs-sink1.hdfs.useLocalTimeStamp = trueagent1.sinks.hdfs-sink1.hdfs.round = trueagent1.sinks.hdfs-sink1.hdfs.roundValue = 10# Finally, now that we've defined all of our components, tell# agent1 which ones we want to activate.agent1.channels = ch1agent1.sources = spooldir-source1agent1.sinks = hdfs-sink1

其中，/home/hadoop/flume-1.7.0/tmpData是我要上传的文件所在目录，也就是，我要将此文件夹下的文件都上传到HDFS上的hdfs://master:9000/test目录。

注意：

• 这样的配置会产生许多小文件，因为默认情况下，一个文件存储10个event，这个配置由rollCount控制，默认为10，此外还有一个参数为rollSize，这个是控制一个文件的大小，如果文件大于这个数值，就是另起一文件。
• 此时的文件名都是以event开头，如果想保留原来文件的名字，可以使用以下配置（其中，basenameHeader是相对source而言，filePrefix是相对sink而言，分别这样设置之后，上传到hdfs上的文件名就会变成“原始文件名.时间戳”）：

agent1.sources.spooldir-source1.basenameHeader = trueagent1.sinks.hdfs-sink1.hdfs.filePrefix = %{basename}agent1.sinks.hdfs-sink1.hdfs.rollSize = 0  agent1.sinks.hdfs-sink1.hdfs.rollCount = 0

2、启动agent
使用以下命令启动agent：

bin/flume-ng agent --conf ./conf/ -f ./conf/flume.conf --name agent1 -Dflume.root.logger=DEBUG,console

3、查看结果
到Hadoop提供的WEB GUI界面可以看到刚刚上传的文件是否成功。
GUI界面地址为：http://master:50070/explorer.html#/test
其中，master为Hadoop的Namenode所在的机器名。

4、总结
在这个场景，需要将文件上传到HDFS上，会使用到几个Hadoop的jar包，分别是：

${HADOOP_HOME}share/hadoop/common/hadoop-common-2.4.0.jar${HADOOP_HOME}share/hadoop/common/lib/commons-configuration-1.6.jar${HADOOP_HOME}share/hadoop/common/lib/hadoop-auth-2.4.0.jar${HADOOP_HOME}share/hadoop/hdfs/hadoop-hdfs-2.4.0.jar

当我使用HDP的Hadoop2.7时，还会用到以下jar包：

common-io-2.4.jarhtrace-core-3.1.0-incubating.jar

以上包都可以在hadoop相关的lib目录下找到

异常

Failed to start agent because dependencies were not found in classpath. Error follows. java.lang.NoClassDefFoundError org/apache/hadoop/io/SequenceFile$CompressionType

2016-11-03 14:49:35,278 (conf-file-poller-0) [ERROR - org.apache.flume.node.PollingPropertiesFileConfigurationProvider$FileWatcherRunnable.run(PollingPropertiesFileConfigurationProvider.java:146)] Failed to start agent because dependencies were not found in classpath. Error follows.java.lang.NoClassDefFoundError: org/apache/hadoop/io/SequenceFile$CompressionType

问题原因：缺少依赖包，这个依赖包是以下jar文件：

${HADOOP_HOME}share/hadoop/common/hadoop-common-2.4.0.jar

解决方法：找到这个jar文件，copy到flume安装目录下的lib目录下就ok了。

java.lang.NullPointerException: Expected timestamp in the Flume event headers, but it was null

2016-11-03 16:32:06,741 (SinkRunner-PollingRunner-DefaultSinkProcessor) [ERROR - org.apache.flume.sink.hdfs.HDFSEventSink.process(HDFSEventSink.java:447)] process failedjava.lang.NullPointerException: Expected timestamp in the Flume event headers, but it was null    at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:204)    at org.apache.flume.formatter.output.BucketPath.replaceShorthand(BucketPath.java:256)    at org.apache.flume.formatter.output.BucketPath.escapeString(BucketPath.java:465)    at org.apache.flume.sink.hdfs.HDFSEventSink.process(HDFSEventSink.java:368)    at org.apache.flume.sink.DefaultSinkProcessor.process(DefaultSinkProcessor.java:67)    at org.apache.flume.SinkRunner$PollingRunner.run(SinkRunner.java:145)    at java.lang.Thread.run(Thread.java:745)

解决方法：
编辑conf/flume.conf文件，其中agent1，sink1替换成你自己的agent和sink

agent1.sinks.sink1.hdfs.useLocalTimeStamp = true

java.lang.NoClassDefFoundError: org/apache/commons/configuration/Configuration

2016-11-03 16:32:55,594 (SinkRunner-PollingRunner-DefaultSinkProcessor) [ERROR - org.apache.flume.sink.hdfs.HDFSEventSink.process(HDFSEventSink.java:447)] process failedjava.lang.NoClassDefFoundError: org/apache/commons/configuration/Configuration    at org.apache.hadoop.metrics2.lib.DefaultMetricsSystem.<init>(DefaultMetricsSystem.java:38)    at org.apache.hadoop.metrics2.lib.DefaultMetricsSystem.<clinit>(DefaultMetricsSystem.java:36)    at org.apache.hadoop.security.UserGroupInformation$UgiMetrics.create(UserGroupInformation.java:106)    at org.apache.hadoop.security.UserGroupInformation.<clinit>(UserGroupInformation.java:208)    at org.apache.hadoop.fs.FileSystem$Cache$Key.<init>(FileSystem.java:2554)    at org.apache.hadoop.fs.FileSystem$Cache$Key.<init>(FileSystem.java:2546)    at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2412)    at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:368)    at org.apache.hadoop.fs.Path.getFileSystem(Path.java:296)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:240)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:232)    at org.apache.flume.sink.hdfs.BucketWriter$9$1.run(BucketWriter.java:668)    at org.apache.flume.auth.SimpleAuthenticator.execute(SimpleAuthenticator.java:50)    at org.apache.flume.sink.hdfs.BucketWriter$9.call(BucketWriter.java:665)    at java.util.concurrent.FutureTask.run(FutureTask.java:266)    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)    at java.lang.Thread.run(Thread.java:745)Caused by: java.lang.ClassNotFoundException: org.apache.commons.configuration.Configuration    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)    ... 18 more

解决方法：
缺少的依赖在commons-configuration-1.6.jar包里，这个包在${HADOOP_HOME}share/hadoop/common/lib/下，将其拷贝到flume的lib目录下。

cp ${HADOOP_HOME}share/hadoop/common/lib/commons-configuration-1.6.jar ${FLUME_HOME}/lib/

java.lang.NoClassDefFoundError: org/apache/hadoop/util/PlatformName

2016-11-03 16:41:54,629 (SinkRunner-PollingRunner-DefaultSinkProcessor) [ERROR - org.apache.flume.sink.hdfs.HDFSEventSink.process(HDFSEventSink.java:447)] process failedjava.lang.NoClassDefFoundError: org/apache/hadoop/util/PlatformName

解决方法：
缺少hadoop-auth-2.4.0.jar依赖，同样将其拷贝到flume的lib目录下：

cp ${HADOOP_HOME}share/hadoop/common/lib/hadoop-auth-2.4.0.jar ${FLUME_HOME}/lib/

HDFS IO error java.io.IOException: No FileSystem for scheme: hdfs

2016-11-03 16:49:26,638 (SinkRunner-PollingRunner-DefaultSinkProcessor) [WARN - org.apache.flume.sink.hdfs.HDFSEventSink.process(HDFSEventSink.java:443)] HDFS IO errorjava.io.IOException: No FileSystem for scheme: hdfs

缺少依赖：hadoop-hdfs-2.4.0.jar

cp ${HADOOP_HOME}share/hadoop/hdfs/hadoop-hdfs-2.4.0.jar ${FLUME_HOME}/lib/

java.lang.NoClassDefFoundError: org/apache/htrace/SamplerBuilder

2016-12-26 09:49:07,854 (SinkRunner-PollingRunner-DefaultSinkProcessor) [ERROR - org.apache.flume.sink.hdfs.HDFSEventSink.process(HDFSEventSink.java:447)] process failedjava.lang.NoClassDefFoundError: org/apache/htrace/SamplerBuilder    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:645)    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:629)    at org.apache.hadoop.hdfs.DistributedFileSystem.initialize(DistributedFileSystem.java:159)    at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:2761)    at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:99)    at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:2795)    at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2777)    at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:386)    at org.apache.hadoop.fs.Path.getFileSystem(Path.java:295)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:240)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:232)    at org.apache.flume.sink.hdfs.BucketWriter$9$1.run(BucketWriter.java:668)    at org.apache.flume.auth.SimpleAuthenticator.execute(SimpleAuthenticator.java:50)    at org.apache.flume.sink.hdfs.BucketWriter$9.call(BucketWriter.java:665)    at java.util.concurrent.FutureTask.run(FutureTask.java:266)    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)    at java.lang.Thread.run(Thread.java:745)Caused by: java.lang.ClassNotFoundException: org.apache.htrace.SamplerBuilder    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)    ... 18 moreException in thread "SinkRunner-PollingRunner-DefaultSinkProcessor" java.lang.NoClassDefFoundError: org/apache/htrace/SamplerBuilder    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:645)    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:629)    at org.apache.hadoop.hdfs.DistributedFileSystem.initialize(DistributedFileSystem.java:159)    at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:2761)    at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:99)    at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:2795)    at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2777)    at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:386)    at org.apache.hadoop.fs.Path.getFileSystem(Path.java:295)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:240)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:232)    at org.apache.flume.sink.hdfs.BucketWriter$9$1.run(BucketWriter.java:668)    at org.apache.flume.auth.SimpleAuthenticator.execute(SimpleAuthenticator.java:50)    at org.apache.flume.sink.hdfs.BucketWriter$9.call(BucketWriter.java:665)    at java.util.concurrent.FutureTask.run(FutureTask.java:266)    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)    at java.lang.Thread.run(Thread.java:745)Caused by: java.lang.ClassNotFoundException: org.apache.htrace.SamplerBuilder    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)    ... 18 more

解决方法：将htrace-core-3.1.0-incubating.jarjar包（这个jar包也可以在Hadoop的安装目录下找到，我的是有lib目录下）拷贝到${FLUME_HOME}/lib/目录下。

java.lang.NoClassDefFoundError: org/apache/commons/io/Charsets

2016-12-26 10:15:36,190 (SinkRunner-PollingRunner-DefaultSinkProcessor) [ERROR - org.apache.flume.sink.hdfs.HDFSEventSink.process(HDFSEventSink.java:447)] process failedjava.lang.NoClassDefFoundError: org/apache/commons/io/Charsets    at org.apache.hadoop.ipc.Server.<clinit>(Server.java:221)    at org.apache.hadoop.ipc.ProtobufRpcEngine.<clinit>(ProtobufRpcEngine.java:71)    at java.lang.Class.forName0(Native Method)    at java.lang.Class.forName(Class.java:348)    at org.apache.hadoop.conf.Configuration.getClassByNameOrNull(Configuration.java:2147)    at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:2112)    at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:2206)    at org.apache.hadoop.ipc.RPC.getProtocolEngine(RPC.java:205)    at org.apache.hadoop.ipc.RPC.getProtocolProxy(RPC.java:579)    at org.apache.hadoop.hdfs.NameNodeProxies.createNNProxyWithClientProtocol(NameNodeProxies.java:419)    at org.apache.hadoop.hdfs.NameNodeProxies.createNonHAProxy(NameNodeProxies.java:315)    at org.apache.hadoop.hdfs.NameNodeProxies.createProxy(NameNodeProxies.java:176)    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:688)    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:629)    at org.apache.hadoop.hdfs.DistributedFileSystem.initialize(DistributedFileSystem.java:159)    at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:2761)    at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:99)    at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:2795)    at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2777)    at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:386)    at org.apache.hadoop.fs.Path.getFileSystem(Path.java:295)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:240)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:232)    at org.apache.flume.sink.hdfs.BucketWriter$9$1.run(BucketWriter.java:668)    at org.apache.flume.auth.SimpleAuthenticator.execute(SimpleAuthenticator.java:50)    at org.apache.flume.sink.hdfs.BucketWriter$9.call(BucketWriter.java:665)    at java.util.concurrent.FutureTask.run(FutureTask.java:266)    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)    at java.lang.Thread.run(Thread.java:745)Caused by: java.lang.ClassNotFoundException: org.apache.commons.io.Charsets    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)    ... 30 moreException in thread "SinkRunner-PollingRunner-DefaultSinkProcessor" java.lang.NoClassDefFoundError: org/apache/commons/io/Charsets    at org.apache.hadoop.ipc.Server.<clinit>(Server.java:221)    at org.apache.hadoop.ipc.ProtobufRpcEngine.<clinit>(ProtobufRpcEngine.java:71)    at java.lang.Class.forName0(Native Method)    at java.lang.Class.forName(Class.java:348)    at org.apache.hadoop.conf.Configuration.getClassByNameOrNull(Configuration.java:2147)    at org.apache.hadoop.conf.Configuration.getClassByName(Configuration.java:2112)    at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:2206)    at org.apache.hadoop.ipc.RPC.getProtocolEngine(RPC.java:205)    at org.apache.hadoop.ipc.RPC.getProtocolProxy(RPC.java:579)    at org.apache.hadoop.hdfs.NameNodeProxies.createNNProxyWithClientProtocol(NameNodeProxies.java:419)    at org.apache.hadoop.hdfs.NameNodeProxies.createNonHAProxy(NameNodeProxies.java:315)    at org.apache.hadoop.hdfs.NameNodeProxies.createProxy(NameNodeProxies.java:176)    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:688)    at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:629)    at org.apache.hadoop.hdfs.DistributedFileSystem.initialize(DistributedFileSystem.java:159)    at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:2761)    at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:99)    at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:2795)    at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2777)    at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:386)    at org.apache.hadoop.fs.Path.getFileSystem(Path.java:295)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:240)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:232)    at org.apache.flume.sink.hdfs.BucketWriter$9$1.run(BucketWriter.java:668)    at org.apache.flume.auth.SimpleAuthenticator.execute(SimpleAuthenticator.java:50)    at org.apache.flume.sink.hdfs.BucketWriter$9.call(BucketWriter.java:665)    at java.util.concurrent.FutureTask.run(FutureTask.java:266)    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)    at java.lang.Thread.run(Thread.java:745)Caused by: java.lang.ClassNotFoundException: org.apache.commons.io.Charsets    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)    ... 30 more

解决方法：将jar包common-io-2.1.jar换成common-io-2.4.jar，此包仍然可以在Hadoop目录下的lib下找到。

Failed to connect to server: node1/172.16.41.54:9000: try once and fail

2016-12-26 10:30:11,538 (hdfs-hdfs-sink1-call-runner-3) [WARN - org.apache.hadoop.ipc.Client$Connection.handleConnectionFailure(Client.java:886)] Failed to connect to server: node1/172.16.41.54:9000: try once and fail.java.net.ConnectException: Connection refused    at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)    at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:717)    at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:206)    at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:531)    at org.apache.hadoop.net.NetUtils.connect(NetUtils.java:495)    at org.apache.hadoop.ipc.Client$Connection.setupConnection(Client.java:650)    at org.apache.hadoop.ipc.Client$Connection.setupIOstreams(Client.java:745)    at org.apache.hadoop.ipc.Client$Connection.access$3200(Client.java:397)    at org.apache.hadoop.ipc.Client.getConnection(Client.java:1618)    at org.apache.hadoop.ipc.Client.call(Client.java:1449)    at org.apache.hadoop.ipc.Client.call(Client.java:1396)    at org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:233)    at com.sun.proxy.$Proxy11.create(Unknown Source)    at org.apache.hadoop.hdfs.protocolPB.ClientNamenodeProtocolTranslatorPB.create(ClientNamenodeProtocolTranslatorPB.java:311)    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)    at java.lang.reflect.Method.invoke(Method.java:498)    at org.apache.hadoop.io.retry.RetryInvocationHandler.invokeMethod(RetryInvocationHandler.java:278)    at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:194)    at org.apache.hadoop.io.retry.RetryInvocationHandler.invoke(RetryInvocationHandler.java:176)    at com.sun.proxy.$Proxy12.create(Unknown Source)    at org.apache.hadoop.hdfs.DFSOutputStream.newStreamForCreate(DFSOutputStream.java:1719)    at org.apache.hadoop.hdfs.DFSClient.create(DFSClient.java:1699)    at org.apache.hadoop.hdfs.DFSClient.create(DFSClient.java:1634)    at org.apache.hadoop.hdfs.DistributedFileSystem$8.doCall(DistributedFileSystem.java:479)    at org.apache.hadoop.hdfs.DistributedFileSystem$8.doCall(DistributedFileSystem.java:475)    at org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)    at org.apache.hadoop.hdfs.DistributedFileSystem.create(DistributedFileSystem.java:475)    at org.apache.hadoop.hdfs.DistributedFileSystem.create(DistributedFileSystem.java:416)    at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:926)    at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:907)    at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:803)    at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:792)    at org.apache.flume.sink.hdfs.HDFSSequenceFile.open(HDFSSequenceFile.java:95)    at org.apache.flume.sink.hdfs.HDFSSequenceFile.open(HDFSSequenceFile.java:78)    at org.apache.flume.sink.hdfs.HDFSSequenceFile.open(HDFSSequenceFile.java:69)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:242)    at org.apache.flume.sink.hdfs.BucketWriter$1.call(BucketWriter.java:232)    at org.apache.flume.sink.hdfs.BucketWriter$9$1.run(BucketWriter.java:668)    at org.apache.flume.auth.SimpleAuthenticator.execute(SimpleAuthenticator.java:50)    at org.apache.flume.sink.hdfs.BucketWriter$9.call(BucketWriter.java:665)    at java.util.concurrent.FutureTask.run(FutureTask.java:266)    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)    at java.lang.Thread.run(Thread.java:745)

解决方法：
连接被拒绝的原因其实挺简单，比如如下：
1、服务进程没开，比如nodenode没开，如果开了，检验IP地址和端口号，apache默认文件系统的端口是9000，而HDP的hadoop的文件系统的端口是8020，而我之前配置的一直是9000，因此会连接不上，所以，只要修改一下conf/flume.conf文件里的配置就好了，把hdfs的那个地址改成8020。
2、防火墙，如果没关防火墙，可能会导致连接不上。

MalformedInputException

2016-12-27 15:53:45,467 (pool-4-thread-1) [ERROR - org.apache.flume.source.SpoolDirectorySource$SpoolDirectoryRunnable.run(SpoolDirectorySource.java:280)] FATAL: Spool Directory source spooldir-source1: { spoolDir: /home/yang/Data/flumeSpoolDir }: Uncaught exception in SpoolDirectorySource thread. Restart or reconfigure Flume to continue processing.java.nio.charset.MalformedInputException: Input length = 1

问题原因：
由于我用的source是spooldir，这个source默认的deserializer是line，而我这里需要传输的文件是avro文件，因此，才出现了这个输入格式异常的情况，因此，解决方法就是修改这个deserializer为avro就可以了，如下：

agent1.sources.spooldir-source1.deserializer = AVRO

参考文献
[1] https://cwiki.apache.org/confluence/display/FLUME/Getting+Started
[2] http://flume.apache.org/FlumeUserGuide.html
[3] http://stackoverflow.com/questions/30645569/expected-timestamp-in-the-flume-event-headers-but-it-was-null
相关资源
[1] https://yq.aliyun.com/articles/33873
[2] https://yq.aliyun.com/articles/50487