Flume2:Flume采集案例

1.采集本地目录的数据至HDFS

1.1 采集需求：
某服务器的某特定目录下，会不断产生新的文件，每当有新文件出现，就需要把文件采集到HDFS中去
1.2 分析:
根据需求，首先定义以下3大要素
采集源，即source——监控文件目录 : spooldir
下沉目标，即sink——HDFS文件系统 : hdfs sink
source和sink之间的传递通道——channel，可用file channel 也可以用内存channel
1.3 采集配置文件编写：

#定义三大组件的名称
agent1.sources = source1
agent1.sinks = sink1
agent1.channels = channel1
# 配置source组件
agent1.sources.source1.type = spooldir
agent1.sources.source1.spoolDir = /home/hadoop/logs/
agent1.sources.source1.fileHeader = false
#配置拦截器
agent1.sources.source1.interceptors = i1
agent1.sources.source1.interceptors.i1.type = host
agent1.sources.source1.interceptors.i1.hostHeader = hostname
# 配置sink组件
agent1.sinks.sink1.type = hdfs
agent1.sinks.sink1.hdfs.path =hdfs://hdp-node-01:9000/weblog/flume-collection/%y-%m-%d/%H-%M
agent1.sinks.sink1.hdfs.filePrefix = access_log
agent1.sinks.sink1.hdfs.maxOpenFiles = 5000
agent1.sinks.sink1.hdfs.batchSize= 100
agent1.sinks.sink1.hdfs.fileType = DataStream
agent1.sinks.sink1.hdfs.writeFormat =Text
agent1.sinks.sink1.hdfs.rollSize = 102400
agent1.sinks.sink1.hdfs.rollCount = 1000000
agent1.sinks.sink1.hdfs.rollInterval = 60
#agent1.sinks.sink1.hdfs.round = true
#agent1.sinks.sink1.hdfs.roundValue = 10
#agent1.sinks.sink1.hdfs.roundUnit = minute
agent1.sinks.sink1.hdfs.useLocalTimeStamp = true
# Use a channel which buffers events in memory
agent1.channels.channel1.type = memory
agent1.channels.channel1.keep-alive = 120
agent1.channels.channel1.capacity = 500000
agent1.channels.channel1.transactionCapacity = 600
# Bind the source and sink to the channel
agent1.sources.source1.channels = channel1
agent1.sinks.sink1.channel = channel1

Channel参数解释：
capacity：默认该通道中最大的可以存储的event数量
trasactionCapacity：每次最大可以从source中拿到或者送到sink中的event数量
keep-alive：event添加到通道中或者移出的允许时间

2.采集文件到HDFS

2.1 采集需求：比如业务系统使用log4j生成的日志，日志内容不断增加，需要把追加到日志文件中的数据实时采集到hdfs
2.2 分析：根据需求，首先定义以下3大要素
采集源，即source——监控文件内容更新 : exec ‘tail -F file’
下沉目标，即sink——HDFS文件系统 : hdfs sink
Source和sink之间的传递通道——channel，可用file channel 也可以用 内存channel
2.3 配置文件编写：

agent1.sources = source1
agent1.sinks = sink1
agent1.channels = channel1
# Describe/configure tail -F source1
agent1.sources.source1.type = exec
agent1.sources.source1.command = tail -F /home/hadoop/logs/access_log
agent1.sources.source1.channels = channel1
#configure host for source
agent1.sources.source1.interceptors = i1
agent1.sources.source1.interceptors.i1.type = host
agent1.sources.source1.interceptors.i1.hostHeader = hostname
# Describe sink1
agent1.sinks.sink1.type = hdfs
#a1.sinks.k1.channel = c1
agent1.sinks.sink1.hdfs.path =hdfs://hdp-node-01:9000/weblog/flume-collection/%y-%m-%d/%H-%M
agent1.sinks.sink1.hdfs.filePrefix = access_log
agent1.sinks.sink1.hdfs.maxOpenFiles = 5000
agent1.sinks.sink1.hdfs.batchSize= 100
agent1.sinks.sink1.hdfs.fileType = DataStream
agent1.sinks.sink1.hdfs.writeFormat =Text
agent1.sinks.sink1.hdfs.rollSize = 102400
agent1.sinks.sink1.hdfs.rollCount = 1000000
agent1.sinks.sink1.hdfs.rollInterval = 60
agent1.sinks.sink1.hdfs.round = true
agent1.sinks.sink1.hdfs.roundValue = 10
agent1.sinks.sink1.hdfs.roundUnit = minute
agent1.sinks.sink1.hdfs.useLocalTimeStamp = true
# Use a channel which buffers events in memory
agent1.channels.channel1.type = memory
agent1.channels.channel1.keep-alive = 120
agent1.channels.channel1.capacity = 500000
agent1.channels.channel1.transactionCapacity = 600
# Bind the source and sink to the channel
agent1.sources.source1.channels = channel1
agent1.sinks.sink1.channel = channel1

更多source和sink组件：
Flume支持众多的source和sink类型，详细手册可参考官方文档
http://flume.apache.org/FlumeUserGuide.html