为什么可选的水槽通道会导致非可选的水槽通道出现问题？

Question

我有一个看似简单的水槽配置，却给我带来了很多问题。让我先描述一下问题，然后列出配置文件。

我有 3 台服务器：服务器 1、服务器 2、服务器 3。

Server1：Netcat源代码/S

Server2,3:Avro源内存通道Kafka接收器

在我的模拟中，服务器2模拟“生产”，因此不会出现任何数据丢失，而服务器3模拟“开发”，数据丢失是正常的。我的假设是，使用2个通道和2个源将使两个服务器相互解耦，如果服务器3宕机，它不会影响服务器2(尤其是使用可选的配置选项！).然而，事实并非如此。当我运行模拟并使用CTRL-C终止Server3时，我在Server2上体验到速度变慢，从Server2到Kafka sink的输出变成了爬行。当我在Server3上恢复Flume代理时，一切都恢复正常。

我没想到会有这种行为。我所期望的是，因为我有两个频道和两个接收器，如果一个频道和/或接收器坏了，另一个频道或接收器应该不会有问题。这是Flume的限制吗？这是源、汇或通道的限制吗？有没有一种方法可以让Flume在我使用一个代理与多个彼此解耦的通道和接收器的情况下运行？我真的不想为每个“环境”（生产和开发）在一台机器上有多个Flume代理。附件是我的配置文件，所以你可以用更技术的方式看到我做了什么：

服务器 1（第一层代理）

#Describe the top level configuration    
agent.sources = mySource
agent.channels = defaultChannel1 defaultChannel2
agent.sinks = mySink1 mySink2

#Describe/configure the source
agent.sources.mySource.type = netcat
agent.sources.mySource.port = 6666
agent.sources.mySource.bind = 0.0.0.0
agent.sources.mySource.max-line-length = 150000
agent.sources.mySource.ack-every-event = false
#agent.sources.mySource.type = syslogtcp
#agent.sources.mySource.host = 0.0.0.0
#agent.sources.mySource.port = 7103
#agent.sources.mySource.eventSize = 150000
agent.sources.mySource.channels = defaultChannel1 defaultChannel2
agent.sources.mySource.selector.type = replicating
agent.sources.mySource.selector.optional = defaultChannel2

#Describe/configure the channel
agent.channels.defaultChannel1.type = memory
agent.channels.defaultChannel1.capacity = 5000
agent.channels.defaultChannel1.transactionCapacity = 200

agent.channels.defaultChannel2.type = memory
agent.channels.defaultChannel2.capacity = 5000
agent.channels.defaultChannel2.transactionCapacity = 200

#Avro Sink
agent.sinks.mySink1.channel = defaultChannel1
agent.sinks.mySink1.type = avro
agent.sinks.mySink1.hostname = Server2
agent.sinks.mySink1.port = 6666

agent.sinks.mySink2.channel = defaultChannel2
agent.sinks.mySink2.type = avro
agent.sinks.mySink2.hostname = Server3
agent.sinks.mySink2.port = 6666

服务器2“生产”水槽代理

#Describe the top level configuration
agent.sources = mySource
agent.channels = defaultChannel
agent.sinks = mySink

#Describe/configure the source
agent.sources.mySource.type = avro
agent.sources.mySource.port = 6666
agent.sources.mySource.bind = 0.0.0.0
agent.sources.mySource.max-line-length = 150000
agent.sources.mySource.channels = defaultChannel

#Describe/configure the interceptor
agent.sources.mySource.interceptors = myInterceptor
agent.sources.mySource.interceptors.myInterceptor.type = myInterceptor$Builder

#Describe/configure the channel
agent.channels.defaultChannel.type = memory
agent.channels.defaultChannel.capacity = 5000
agent.channels.defaultChannel.transactionCapacity = 200

#Describe/configure the sink
agent.sinks.mySink.type = org.apache.flume.sink.kafka.KafkaSink
agent.sinks.mySink.topic = Server2-topic
agent.sinks.mySink.brokerList = broker1:9092, broker2:9092
agent.sinks.mySink.requiredAcks = -1
agent.sinks.mySink.batchSize = 100
agent.sinks.mySink.channel = defaultChannel

SERVER3“开发”FLUME代理

#Describe the top level configuration
agent.sources = mySource
agent.channels = defaultChannel
agent.sinks = mySink

#Describe/configure the source
agent.sources.mySource.type = avro
agent.sources.mySource.port = 6666
agent.sources.mySource.bind = 0.0.0.0
agent.sources.mySource.max-line-length = 150000
agent.sources.mySource.channels = defaultChannel

#Describe/configure the interceptor
agent.sources.mySource.interceptors = myInterceptor
agent.sources.mySource.interceptors.myInterceptor.type = myInterceptor$Builder

#Describe/configure the channel
agent.channels.defaultChannel.type = memory
agent.channels.defaultChannel.capacity = 5000
agent.channels.defaultChannel.transactionCapacity = 200

#Describe/configure the sink
agent.sinks.mySink.type = org.apache.flume.sink.kafka.KafkaSink
agent.sinks.mySink.topic = Server3-topic
agent.sinks.mySink.brokerList = broker1:9092, broker2:9092
agent.sinks.mySink.requiredAcks = -1
agent.sinks.mySink.batchSize = 100
agent.sinks.mySink.channel = defaultChannel 

谢谢你的帮助！

Answer 1

我会考虑调整这个配置参数，因为它与内存通道有关：

agent.channels.defaultChannel.capacity=5000agent.channels.defaultChannel.transaction容量=200

可能先尝试加倍，然后再次执行测试，您应该会看到改进：

代理.通道.默认通道.容量 = 10000 代理.通道.默认通道.事务容量 = 400

在测试期间观察Apache Flume实例的JVM也很好