flume启动时，如果没有通过参数(--name 或者 - n)指定代理，那么默认使用tier1作为代理名称，启动成功后，不会报错，但是可能会提示如题警告。

flume.conf配置文件默认就是用tier1作为代理名称。如下所示。

这个实例是网上一个正好使用了默认tier1作为agent，但是启动时却使用了"agent"作为agent,有点多余。再联系本文，不难推测这里启动时应该指定-n tier1。

指定正确的agent之后，启动会出现如下所示的日志。

2018-02-22 15:37:03,557 INFO org.apache.flume.node.PollingPropertiesFileConfigurationProvider: Configuration provider starting
2018-02-22 15:37:03,582 INFO org.apache.flume.node.PollingPropertiesFileConfigurationProvider: Reloading configuration file:/opt/cm-5.12.0/run/cloudera-scm-agent/process/196-flume-AGENT/flume.conf
2018-02-22 15:37:03,587 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,587 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,587 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,587 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,587 INFO org.apache.flume.conf.FlumeConfiguration: Added sinks: hdfs-sink-1 Agent: agent1
2018-02-22 15:37:03,588 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,588 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,588 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,588 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,588 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,588 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,588 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,588 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,588 INFO org.apache.flume.conf.FlumeConfiguration: Processing:hdfs-sink-1
2018-02-22 15:37:03,603 INFO org.apache.flume.conf.FlumeConfiguration: Post-validation flume configuration contains configuration for agents: [agent1]
2018-02-22 15:37:03,603 INFO org.apache.flume.node.AbstractConfigurationProvider: Creating channels
2018-02-22 15:37:03,654 INFO org.apache.flume.channel.DefaultChannelFactory: Creating instance of channel file-channel-1 type file
2018-02-22 15:37:03,686 INFO org.apache.flume.node.AbstractConfigurationProvider: Created channel file-channel-1
2018-02-22 15:37:03,687 INFO org.apache.flume.source.DefaultSourceFactory: Creating instance of source kafka-source-1, type org.apache.flume.source.kafka.KafkaSource

如果是通过clouder-manager部署的flume,可以直接在实例配置界面做配置。