Flume-Failover Sink Processor 故障转移与 Load balancing Sink 负载均衡

接上一篇：https://www.cnblogs.com/jhxxb/p/11579518.html

使用 Flume1 监控一个端口，其 sink 组中的 sink 分别对接 Flume2 和 Flume3，采用 Failover Sink Processor，实现故障转移的功能。

一、创建配置文件

1.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 flumeflume-console1 和 flume-flume-console2。

# 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 = 127.0.0.1
a1.sources.r1.port = 4444

# Sink Group
a1.sinkgroups.g1.processor.type = failover
a1.sinkgroups.g1.processor.priority.k1 = 5
a1.sinkgroups.g1.processor.priority.k2 = 10
a1.sinkgroups.g1.processor.maxpenalty = 10000

# Describe the sink
a1.sinks.k1.type = avro
a1.sinks.k1.hostname = h136
a1.sinks.k1.port = 4141
a1.sinks.k2.type = avro
a1.sinks.k2.hostname = h136
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

2.flume-flume-console1.conf

配置上级 Flume 输出的 Source，输出是到本地控制台。

# 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 = h136
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

3.flume-flume-console2.conf

配置上级 Flume 输出的 Source，输出是到本地控制台。

# 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 = h136
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

二、测试

1.故障转移

由于 flume-netcat-flume.conf 向另外两个发送数据，即 flume-flume-console1.conf 和 flume-flume-console2.conf 为服务端接收数据，需要在 flume-netcat-flume.conf 之前启动。

cd /opt/apache-flume-1.9.0-bin

bin/flume-ng agent --conf conf/ --name a3 --conf-file /tmp/flume-job/group2/flume-flume-console2.conf -Dflume.root.logger=INFO,console
bin/flume-ng agent --conf conf/ --name a2 --conf-file /tmp/flume-job/group2/flume-flume-console1.conf -Dflume.root.logger=INFO,console
bin/flume-ng agent --conf conf/ --name a1 --conf-file /tmp/flume-job/group2/flume-netcat-flume.conf -Dflume.root.logger=INFO,console

启动后，由于 flume-netcat-flume.conf 配置中 console1 的优先级高于 console2，所以会优先连接 console1。

向监控端口发送消息

yum -y install nc
nc 127.0.0.1 4444

123456

可以看到只有 netcat 和 console1 和 会接收到数据，这时把 console1 结束掉，模拟 console1 故障，这时 netcat 会自动去连接 console2，再发送消息就是只有 netcat 和 console2 接收到数据了。

2.负载均衡

使用 Load balancing Sink 完成，和故障转移差不多，只是在连接时不在是只连接 console1，而是在 console1 和 console2 之间切换。

要修改 flume-netcat-flume.conf 的配置

# 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 = 127.0.0.1
a1.sources.r1.port = 4444

# Sink Group
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 = h136
a1.sinks.k1.port = 4141
a1.sinks.k2.type = avro
a1.sinks.k2.hostname = h136
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

测试和故障转移一样，只是在用 nc 发送消息时会随机发送到 console1 和 console2 其中的一个，不在固定。