flume处理事务的流程分为两个部分(两个事件),数据输入端(Source–Channel端)和数据输出端(Channel—Sink端)。
数据输入端:Source将数据从web服务器抓取过来,然后进行doput到putList临时缓冲区,putList是一个队列形式的缓冲区,然后doCommit将putList提交到Channel中,doCommit检查Channel中的内存队列是否能够合并,如果能够合并,将一组数据放到一个事务中进行传递,当putList内存缓冲区中的空间不够使用时才会发生doRollback,进行事务回滚。
数据输出端:发生再channel与sink之间的事务,doTake将数据抓取到takeList缓冲区中,并进行写入HDFS中。doCommit将一组数据发送到Sink中,并判断数据是否全部发送成功,发送成功后,清空缓冲区。如果这一组数据中,有任何一个没有发送成功,doRollback就会将tabkeList中的数据回滚到channel中。
FlumeAgent内部原理
Source接收到Web服务器发送的数据后交给Channel中的事件处理器Channel Processor,时间处理器内部进行将数据传递给拦截器,对事件进行分类,加标记等一系列自定义拦截器处理,接着将每个事件交给Channe Selector(Channel选择器),进行选择相对应的Channel(传输通道),经过channel后,交给SinkProcessor,进行分配Sink(下沉组件),输出到目的地。
重要组件
ChannelSelector 的作用就是选出 Event 将要被发往哪个 Channel。其共有两种类型,分别是 Replicating(复制)和 Multiplexing(多路复用)。
ReplicatingSelector 会将同一个发往所有的,会根据相应的原则,将不同的发往不同的。
SinkProcessor
SinkProcessor共有三种类型,分别是:
DefaultSinkProcessor:对应的是单个的 Sink。
LoadBalancingSinkProcessor:对应的是 Sink Group,可以实现负载均衡的功能。
FailoverSinkProcessor: Sink Group
Flume的拓扑结构
简单串联:将多个flume线性串联起来。此模式不建议桥接过多的flume,flume数量过多会影响传输效率,一旦某个节点flume宕机,整个传输系统将会崩溃。
复制和多路复用
Flume支持将事件流向一个或者多个目的地。这种模式可以将相同数据复制到多个channel中,或者将不同数据分发到不同的channel中,sink可以选择传送到不同的目的地。
这种模式是我们最常见的,也非常实用,日常 web 应用通常分布在上百个服务器,大者甚至上千个、上万个服务器。产生的日志,处理起来也非常麻烦。用 flume 的这种组合方式能很好的解决这一问题,每台服务器部署一个 flume 采集日志,传送到一个集中收集日志的flume,再由此 flume 上传到 hdfs、hive、hbase 等,进行日志分析。
企业开发
复制和多路复用
1 案例需求
使用 Flume-1 监控文件变动,Flume-1 将变动内容传递给 Flume-2,Flume-2 负责存储到 HDFS。同时 Flume-1 将变动内容传递给Flume-3,Flume-3 负责输出到Local FileSystem。
2 需求分析
flume-1:Exec Source -- Memory Channel --Avro、 Sink
flume-2:Avro Source -- Memory Channel --HDFS Sink
flume-3:Avro Source -- Memory Channel -- File_roll Sink
3 实现步骤
1. 准备工作
在/opt/module/flume/job 目录下创建 group1 文件夹
[ityouxin@hadoop102 job]$ mkdir group1
在/opt/module/datas/目录下创建 flume3 文件夹
[ityouxin@hadoop102 datas]$ mkdir flume3
2. 创建 flume-file-flume.conf
配置 1 个接收日志文件的 source 和两个 channel、两个 sink,分别输送给 flume-flume- hdfs 和 flume-flume-dir。
编辑配置文件:
[ityouxin@hadoop102 group1]$ vim flume-file-flume.conf
添加如下内容:
# Name the components on this agent
a1.sources = r1
a1.sinks = k1 k2
a1.channels = c1 c2
# 将数据流复制给所有 channel
a1.sources.r1.selector.type = replicating
# Describe/configure the source
a1.sources.r1.type = exec
a1.sources.r1.command = tail -F /opt/module/hive/logs/hive.log a1.sources.r1.shell = /bin/bash -c
# Describe the sink
# sink 端的 avro 是一个数据发送者
a1.sinks.k1.type = avro
a1.sinks.k1.hostname = hadoop102
a1.sinks.k1.port = 4141
a1.sinks.k2.type = avro
a1.sinks.k2.hostname = hadoop102
a1.sinks.k2.port = 4142
# Describe the channel
a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100
a1.channels.c2.type = memory
a1.channels.c2.capacity = 1000
a1.channels.c2.transactionCapacity = 100
# Bind the source and sink to the channel
a1.sources.r1.channels = c1 c2
a1.sinks.k1.channel = c1
a1.sinks.k2.channel = c2
3. 创建 flume-flume-hdfs.conf
配置上级 Flume 输出的 Source,输出是到 HDFS 的Sink。
编辑配置文件:
[ityouxin@hadoop102 group1]$ vim flume-flume-hdfs.conf
添加如下内容:
# Name the components on this agent
a2.sources = r1
a2.sinks = k1
a2.channels = c1
# Describe/configure the source
# source 端的 avro 是一个数据接收服务
a2.sources.r1.type = avro
a2.sources.r1.bind = hadoop102
a2.sources.r1.port = 4141
# Describe the sink
a2.sinks.k1.type = hdfs
a2.sinks.k1.hdfs.path = hdfs://hadoop102:9000/flume2/%Y%m%d/%H
#上传文件的前缀
a2.sinks.k1.hdfs.filePrefix = flume2-
#是否按照时间滚动文件夹
a2.sinks.k1.hdfs.round = true
#多少时间单位创建一个新的文件夹
a2.sinks.k1.hdfs.roundValue = 1
#重新定义时间单位
a2.sinks.k1.hdfs.roundUnit = hour
#是否使用本地时间戳
a2.sinks.k1.hdfs.useLocalTimeStamp = true
#积攒多少个 Event 才 flush 到 HDFS 一次
a2.sinks.k1.hdfs.batchSize = 100
#设置文件类型,可支持压缩
a2.sinks.k1.hdfs.fileType = DataStream
#多久生成一个新的文件
a2.sinks.k1.hdfs.rollInterval = 600
#设置每个文件的滚动大小大概是 128M
a2.sinks.k1.hdfs.rollSize = 134217700
#文件的滚动与 Event 数量无关
a2.sinks.k1.hdfs.rollCount = 0
# Describe the channel
a2.channels.c1.type = memory
a2.channels.c1.capacity = 1000
a2.channels.c1.transactionCapacity =100
# Bind the source and sink to the channel
a2.sources.r1.channels = c1
a2.sinks.k1.channel = c1
4. 创建 flume-flume-dir.conf
配置上级 Flume 输出的 Source,输出是到本地目录的 Sink。
编辑配置文件:
[ityouxin@hadoop102 group1]$ vim flume-flume-dir.conf
添加如下内容:
# Name the components on this agent
a3.sources = r1
a3.sinks = k1
a3.channels =c2
# Describe/configure the source
a3.sources.r1.type = avro
a3.sources.r1.bind = hadoop102
a3.sources.r1.port = 4142
# Describe the sink
a3.sinks.k1.type =file_roll
a3.sinks.k1.sink.directory = /opt/module/data/flume3
# Describe the channel
a3.channels.c2.type = memory
a3.channels.c2.capacity =1000
a3.channels.c2.transactionCapacity = 100
# Bind the source and sink to the channel
a3.sources.r1.channels = c2
a3.sinks.k1.channel = c2
提示:输出的本地目录必须是已经存在的目录,如果该目录不存在,并不会创建新的目录。
5. 执行配置文件
分别启动对应的 flume 进程:
flume-flume-dir,flume-flume-hdfs,flume-file-flume。
[ityouxin@hadoop102 flume]$ bin/flume-ng agent --conf a3 --conf-file job/group1/flume-flume-dir.conf
[ityouxin@hadoop102 flume]$ bin/flume-ng agent --conf a2 --conf-file job/group1/flume-flume-hdfs.conf
[ityouxin@hadoop102 flume]$ bin/flume-ng agent --conf a1 --conf-file job/group1/flume-file-flume.conf
6. 启动 Hadoop 和 Hive
[ityouxin@hadoop102 hadoop-2.7.2]$ sbin/start-dfs.sh
[ityouxin@hadoop103 hadoop-2.7.2]$ sbin/start-yarn.sh
[ityouxin@hadoop102 hive]$ bin/hive
hive (default)>insert into student values(1,"lhx");
故障转移
1 案例需求
使用 Flume1 监控一个端口,其 sink 组中的 sink 分别对接 Flume2 和Flume3,采用FailoverSinkProcessor,实现故障转移的功能。
2 需求分析
flume-1:netcat Source -- Memory Channel -- avro Sink
flume-2:avro Source -- Memory Channel -- logger Sink
flume-3:avro Source -- Memory Channel -- logger Sink
3 实现步骤
1. 准备工作
在/opt/module/flume/job 目录下创建 group2 文件夹
[ityouxin@hadoop102 job]$ cd group2/
2. 创建 flume-netcat-flume.conf
配置 1 个 netcat source 和 1 个 channel、1 个 sink group(2 个 sink),分别输送给 flume- flume-console1 和 flume-flume-console2。
编辑配置文件:
[ityouxin@hadoop102 group2]$ vim flume-netcat-flume.conf
添加如下内容:
# Name the components on this agent
a1.sources = r1
a1.channels = c1
a1.sinkgroups = g1
a1.sinks = k1 k2
# Describe/configure the source
a1.sources.r1.type = netcat
a1.sources.r1.bind = localhost
a1.sources.r1.port = 44444
a1.sinkgroups.g1.processor.type = failover a1.sinkgroups.g1.processor.priority.k1 = 5
a1.sinkgroups.g1.processor.priority.k2 = 10
# 退避期是10秒
a1.sinkgroups.g1.processor.maxpenalty = 10000
# Describe the sink
a1.sinks.k1.type = avro
a1.sinks.k1.hostname = hadoop102
a1.sinks.k1.port = 4141
a1.sinks.k2.type = avro
a1.sinks.k2.hostname = hadoop102
a1.sinks.k2.port = 4142
# Describe the channel
a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100
# Bind the source and sink to the channel
a1.sources.r1.channels = c1
a1.sinkgroups.g1.sinks = k1 k2
a1.sinks.k1.channel = c1
a1.sinks.k2.channel = c1
3. 创建 flume-flume-console1.conf
配置上级 Flume 输出的 Source,输出是到本地控制台。
编辑配置文件:
[ityouxin@hadoop102 group2]$ vim flume-flume-console1.conf
添加如下内容:
# Name the components on this agent
a2.sources = r1
a2.sinks = k1
a2.channels = c1
# Describe/configure the source
a2.sources.r1.type = avro
a2.sources.r1.bind = hadoop102
a2.sources.r1.port = 4141
# Describe the sink
a2.sinks.k1.type = logger
# Describe the channel
a2.channels.c1.type = memory
a2.channels.c1.capacity = 1000
a2.channels.c1.transactionCapacity = 100
# Bind the source and sink to the channel
a2.sources.r1.channels = c1
a2.sinks.k1.channel = c1
4. 创建 flume-flume-console2.conf
配置上级 Flume 输出的 Source,输出是到本地控制台。
编辑配置文件:
[ityouxin@hadoop102 group2]$ vim flume-flume-console2.conf
添加如下内容:
# Name the components on this agent a3.sources = r1
a3.sinks = k1
a3.channels = c2
# Describe/configure the source
a3.sources.r1.type = avro
a3.sources.r1.bind = hadoop102
a3.sources.r1.port = 4142
# Describe the sink
a3.sinks.k1.type = logger
# Describe the channel
a3.channels.c2.type = memory
a3.channels.c2.capacity = 1000
a3.channels.c2.transactionCapacity = 100
# Bind the source and sink to the channel
a3.sources.r1.channels = c2
a3.sinks.k1.channel = c2
5. 执行配置文件
分别开启对应配置文件:flume-flume-console2,flume-flume-console1,flume-netcat-flume。
[ityouxin@hadoop102 flume]$ bin/flume-ng agent --conf conf/ --name a3 --conf-file job/group2/flume-flume-console2.conf -Dflume.root.logger=INFO,console
[ityouxin@hadoop102 flume]$ bin/flume-ng agent --conf conf/ --name a2 --conf-file job/group2/flume-flume-console1.conf -Dflume.root.logger=INFO,console
[ityouxin@hadoop102 flume]$ bin/flume-ng agent --conf conf/ --name a1 --conf-file job/group2/flume-netcat-flume.conf
6. 使用 netcat 工具向本机的 44444 端口发送内容
$ nc localhost 44444
7. 查看 Flume2 及 Flume3 的控制台打印日志
8. 将 Flume2 kill,观察 Flume3 的控制台打印情况。
注:使用 jps -ml 查看 Flume 进程。
负载均衡
1 案例需求
使用 Flume1 监控一个端口,其 sink 组中的 sink 分别对接 Flume2 和Flume3,采用LoadBalancingSinkProcessor,实现负载均衡的功能。
2 需求分析
flume-1:netcat Source -- Memory Channel -- avro Sink
flume-2:avro Source -- Memory Channel -- logger Sink
flume-3:avro Source -- Memory channel -- logger Sink
3 实现步骤
1. 准备工作
在/opt/module/flume/job 目录下创建 group2 文件夹
[ityouxin@hadoop102 job]$ cd group2/
2. 创建 flume-netcat-flume.conf
配置 1 个 netcat source 和 1 个 channel、1 个 sink group(2 个 sink),分别输送给 flume- flume-console1 和 flume-flume-console2。
编辑配置文件:
[ityouxin@hadoop102 group2]$ vim flume-netcat-flume.conf
添加如下内容:
# Name the components on this agent
a1.sources = r1
a1.channels = c1
a1.sinkgroups = g1
a1.sinks = k1 k2
# Describe/configure the source
a1.sources.r1.type = netcat
a1.sources.r1.bind = localhost
a1.sources.r1.port = 44444
# 配置负载均衡
a1.sinkgroups.g1.sinks = k1 k2
a1.sinkgroups.g1.processor.type = load_balance
a1.sinkgroups.g1.processor.backoff = true
a1.sinkgroups.g1.processor.selector = random
# Describe the sink
a1.sinks.k1.type = avro
a1.sinks.k1.hostname = hadoop102
a1.sinks.k1.port = 4141
a1.sinks.k2.type = avro
a1.sinks.k2.hostname = hadoop102
a1.sinks.k2.port = 4142
# Describe the channel
a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100
# Bind the source and sink to the channel
a1.sources.r1.channels = c1
a1.sinkgroups.g1.sinks = k1 k2
a1.sinks.k1.channel = c1
a1.sinks.k2.channel = c1
3. 创建 flume-flume-console1.conf
配置上级 Flume 输出的 Source,输出是到本地控制台。
编辑配置文件:
[ityouxin@hadoop102 group2]$ vim flume-flume-console1.conf
添加如下内容:
# Name the components on this agent
a2.sources = r1
a2.sinks = k1
a2.channels = c1
# Describe/configure the source
a2.sources.r1.type = avro
a2.sources.r1.bind = hadoop102
a2.sources.r1.port = 4141
# Describe the sink
a2.sinks.k1.type = logger
# Describe the channel
a2.channels.c1.type = memory
a2.channels.c1.capacity = 1000
a2.channels.c1.transactionCapacity = 100
# Bind the source and sink to the channel
a2.sources.r1.channels = c1
a2.sinks.k1.channel = c1
4. 创建 flume-flume-console2.conf
配置上级 Flume 输出的 Source,输出是到本地控制台。
编辑配置文件:
[ityouxin@hadoop102 group2]$ vim flume-flume-console2.conf
添加如下内容:
# Name the components on this agent a3.sources = r1
a3.sinks = k1
a3.channels = c2
# Describe/configure the source
a3.sources.r1.type = avro
a3.sources.r1.bind = hadoop102
a3.sources.r1.port = 4142
# Describe the sink
a3.sinks.k1.type = logger
# Describe the channel
a3.channels.c2.type = memory
a3.channels.c2.capacity = 1000
a3.channels.c2.transactionCapacity = 100
# Bind the source and sink to the channel
a3.sources.r1.channels = c2
a3.sinks.k1.channel = c2
5. 执行配置文件
分别开启对应配置文件:flume-flume-console2,flume-flume-console1,flume-netcat-flume。
[ityouxin@hadoop102 flume]$ bin/flume-ng agent --conf conf/ --name a3 --conf-file job/group2/flume-flume-console2.conf -Dflume.root.logger=INFO,console
[ityouxin@hadoop102 flume]$ bin/flume-ng agent --conf conf/ --name a2 --conf-file job/group2/flume-flume-console1.conf -Dflume.root.logger=INFO,console
[ityouxin@hadoop102 flume]$ bin/flume-ng agent --conf conf/ --name a1 --conf-file job/group2/flume-netcat-flume.conf
6. 使用 netcat 工具向本机的 44444 端口发送内容
$ nc localhost 44444
7. 查看 Flume2 及 Flume3 的控制台打印日志
8. 将 Flume2 kill,观察 Flume3 的控制台打印情况。
注:使用 jps -ml 查看 Flume 进程。
聚合
1 需求分析
hadoop102 上的Flume-1 监控文件/opt/module/data/group.log,hadoop103 上的Flume-2 监控某一个端口的数据流,Flume-1 与 Flume-2 将数据发送hadoop104 上的 Flume-3,Flume-3 将最终数据打印到控制台。
2 案例分析
hadoop102:flume-1:Exec Source -- Memory Channel -- Arvo Source
hadoop103:flume-2:Netcat Source -- Memory Channel --Avro Sink
hadoop104:flume-3:Avro Source -- Memory Channel -- logger Channel
3 实现步骤
1. 准备工作
分发 Flume
[ityouxin@hadoop102 module]$ xsync flume
在hadoop102、hadoop103 以及hadoop104 的/opt/module/flume/job 目录下创建一个group3文件夹。
[ityouxin@hadoop102 job]$ mkdir group3
[ityouxin@hadoop103 job]$ mkdir group3
[ityouxin@hadoop104 job]$ mkdir group3
2. 创建 flume1-logger-flume.conf
配置 Source 用于监控 hive.log 文件,配置 Sink 输出数据到下一级 Flume。在 hadoop102 上编辑配置文件
[ityouxin@hadoop102 group3]$ vim flume1-logger-flume.conf
添加如下内容:
# Name the components on this agent
a1.sources = r1
a1.sinks = k1
a1.channels = c1
# Describe/configure the source
a1.sources.r1.type = exec
a1.sources.r1.command = tail -F /opt/module/group.log a1.sources.r1.shell = /bin/bash -c
# Describe the sink
a1.sinks.k1.type = avro
a1.sinks.k1.hostname = hadoop104
a1.sinks.k1.port = 4141
# Describe the channel
a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100
# Bind the source and sink to the channel
a1.sources.r1.channels = c1
a1.sinks.k1.channel = c1
3. 创建 flume2-netcat-flume.conf
配置 Source 监控端口 44444 数据流,配置 Sink 数据到下一级 Flume:在 hadoop103 上编辑配置文件
[ityouxin@hadoop102 group3]$ vim flume2-netcat-flume.conf
添加如下内容
# Name the components on this agent
a2.sources = r1
a2.sinks = k1
a2.channels = c1
# Describe/configure the source
a2.sources.r1.type = netcat
a2.sources.r1.bind = hadoop103
a2.sources.r1.port = 44444
# Describe the sink
a2.sinks.k1.type = avro
a2.sinks.k1.hostname = hadoop104
a2.sinks.k1.port = 4141
# Use a channel which buffers events in memory a2.channels.c1.type = memory
a2.channels.c1.capacity = 1000
a2.channels.c1.transactionCapacity = 100
# Bind the source and sink to the channel
a2.sources.r1.channels = c1
a2.sinks.k1.channel = c1
4. 创建 flume3-flume-logger.conf
配置 source 用于接收 flume1 与 flume2 发送过来的数据流,最终合并后 sink 到控制台。在 hadoop104 上编辑配置文件
[ityouxin@hadoop104 group3]$ touch flume3-flume-logger.conf
[ityouxin@hadoop104 group3]$ vim flume3-flume-logger.conf
添加如下内容
# Name the components on this agent
a3.sources = r1
a3.sinks = k1
a3.channels = c1
# Describe/configure the source
a3.sources.r1.type = avro
a3.sources.r1.bind = hadoop104
a3.sources.r1.port = 4141
# Describe the sink
a3.sinks.k1.type = logger
# Describe the channel
a3.channels.c1.type = memory
a3.channels.c1.capacity = 1000
a3.channels.c1.transactionCapacity = 100
# Bind the source and sink to the channel
a3.sources.r1.channels = c1
a3.sinks.k1.channel = c1
5. 执行配置文件
分别开启对应配置文件:flume3-flume-logger.conf,flume2-netcat-flume.conf,flume1- logger-flume.conf。
[ityouxin@hadoop104 flume]$ bin/flume-ng agent --conf conf/ --name a3 -conf-file job/group3/flume3-flume-logger.conf -Dflume.root.logger=INFO,console
[ityouxin@hadoop102 flume]$ bin/flume-ng agent --conf conf/ --name a2 --conf-file job/group3/flume1-logger-flume.conf
[ityouxin@hadoop103 flume]$ bin/flume-ng agent --conf conf/ --name a1 --conf-file job/group3/flume2-netcat-flume.conf
6. 在 hadoop103 上向/opt/module 目录下的 group.log 追加内容
[ityouxin@hadoop103 module]$ echo 'hello' > group.log
7. 在 hadoop102 上向 44444 端口发送数据
[ityouxin@hadoop102 flume]$ nc localhost 44444
8. 检查 hadoop104 上数据