Flume HDFS接收器仅使用netcat源存储一行数据源

Question

我尝试使用Flume 1.7将数据加载到HDFS中。我创建了以下配置：

# Starting with: /opt/flume/bin/flume-ng agent -n Agent -c conf -f /opt/flume/conf/test.conf
# Naming the components on the current agent
Agent.sources = Netcat   
Agent.channels = MemChannel 
Agent.sinks = LoggerSink hdfs-sink LocalOut

# Describing/Configuring the source 
Agent.sources.Netcat.type = netcat 
Agent.sources.Netcat.bind = 0.0.0.0
Agent.sources.Netcat.port = 56565  

# Describing/Configuring the sink 
Agent.sinks.LoggerSink.type = logger  

# Define a sink that outputs to hdfs.
Agent.sinks.hdfs-sink.type = hdfs
Agent.sinks.hdfs-sink.hdfs.path = hdfs://<<IP of HDFS node>>:8020/user/admin/flume_folder/%y-%m-%d/%H%M/
Agent.sinks.hdfs-sink.hdfs.useLocalTimeStamp = true
Agent.sinks.hdfs-sink.hdfs.fileType = DataStream
Agent.sinks.hdfs-sink.hdfs.writeFormat = Text
Agent.sinks.hdfs-sink.hdfs.batchSize = 100
Agent.sinks.hdfs-sink.hdfs.rollSize = 0
Agent.sinks.hdfs-sink.hdfs.rollCount = 0
Agent.sinks.hdfs-sink.hdfs.rollInterval = 0
Agent.sinks.hdfs-sink.hdfs.idleTimeout = 0

# Schreibt input into local Filesystem
#http://flume.apache.org/FlumeUserGuide.html#file-roll-sink
Agent.sinks.LocalOut.type = file_roll  
Agent.sinks.LocalOut.sink.directory = /tmp/flume
Agent.sinks.LocalOut.sink.rollInterval = 0  


# Describing/Configuring the channel 
Agent.channels.MemChannel.type = memory 
Agent.channels.MemChannel.capacity = 1000 
Agent.channels.MemChannel.transactionCapacity = 100 

# Bind the source and sink to the channel 
Agent.sources.Netcat.channels = MemChannel
Agent.sinks.LoggerSink.channel = MemChannel
Agent.sinks.hdfs-sink.channel = MemChannel
Agent.sinks.LocalOut.channel = MemChannel

之后，我使用 netcat 将以下文件发送到源：

cat textfile.csv | nc <IP of flume agent> 56565

该文件包含以下元素:

Name1,1
Name2,2
Name3,3
Name4,4
Name5,5
Name6,6
Name7,7
Name8,8
Name9,9
Name10,10
Name11,11
Name12,12
Name13,13
Name14,14
Name15,15
Name16,16
Name17,17
Name18,18
Name19,19
Name20,20
...
Name490,490
Name491,491
Name492,492

我面临的问题是，没有任何错误，flume正在写入hdfs，但只有一行传输的文件。如果您开始使用nectat多次将文件推送到源文件，那么有时flume会将多个文件写入hdfs，包括多个行。但很少是所有行。

我试图改变hdfs参数roll大小，批量大小和其他，但它并没有真正改变的行为。

也配置了本地文件的接收器工作正常。

有人知道如何配置它以确保所有条目都写入hdfs而不会丢失条目吗？

谢谢你的帮助。

更新1.12.2016

我删除了除HDFS接收器外的所有接收器，并更改了一些参数。在此之后，HDFS接收器按其应有的方式运行。

这里的配置:

# Naming the components on the current agent
Agent.sources = Netcat   
Agent.channels = MemChannel 
Agent.sinks = hdfs-sink 

# Describing/Configuring the source 
Agent.sources.Netcat.type = netcat 
Agent.sources.Netcat.bind = 0.0.0.0
Agent.sources.Netcat.port = 56565  


# Define a sink that outputs to hdfs.
Agent.sinks.hdfs-sink.type = hdfs
Agent.sinks.hdfs-sink.hdfs.path = hdfs://<<IP of HDFS node>>/user/admin/flume_folder/%y-%m-%d/%H%M/
Agent.sinks.hdfs-sink.hdfs.useLocalTimeStamp = true
Agent.sinks.hdfs-sink.hdfs.fileType = DataStream
Agent.sinks.hdfs-sink.hdfs.writeFormat = Text
Agent.sinks.hdfs-sink.hdfs.batchSize = 100
Agent.sinks.hdfs-sink.hdfs.rollSize = 0
Agent.sinks.hdfs-sink.hdfs.rollCount = 100


# Describing/Configuring the channel 
Agent.channels.MemChannel.type = memory 
Agent.channels.MemChannel.capacity = 1000 
Agent.channels.MemChannel.transactionCapacity = 100 

# Bind the source and sink to the channel 
Agent.sources.Netcat.channels = MemChannel
Agent.sinks.hdfs-sink.channel = MemChannel

有人知道为什么它在这种配置下工作，但在两个或更多的水槽下就不再工作了吗？

Answer 1

我自己找到了解决方案。据我所知，我为两个接收器使用了相同的通道。因此，更快的接收器接管了所有条目，只有部分条目被传递到hdfs接收器。

使用不同的通道并使用参数为源包括扇动后

Agent.sources.Netcat.selector.type = replicating

Flume 按预期写入本地文件和 hdfs。