SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in [jar:file:/usr/local/flume-1.7.0/lib/slf4j-log4j12-1.6.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/usr/local/hadoop-2.7.1/share/hadoop/common/lib/slf4j-log4j12-1.7.10.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/usr/local/hbase-1.1.5/lib/slf4j-log4j12-1.7.5.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See http://www.slf4j.org/codes.html#multiple_bindings for an explanation.
log4j:WARN No appenders could be found for logger (org.apache.flume.node.PollingPropertiesFileConfigurationProvider).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
Hbase和Flume的slf4j-log4j12-x.x.xx.jar与hadoop的slf4j-log4j12-x.x.xx.jar冲突（版本不一致）
查询并「删掉」或者「修改」命名，如下图：
重新开启Flume客户端监听
bin/flume-ng agent --conf conf/ --name a1 --conf-file job/flume-netcat-logger.conf -Dflume.root.logger = INFO,console
监听启动不成功：
log4j:WARN No appenders could be found for logger (org.apache.flume.node.PollingPropertiesFileConfigurationProvider).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
注意
bin/flume-ng agent --conf conf/ --name a1 --conf-file job/flume-netcat-logger.conf -Dflume.root.logger=INFO,console
-Dflume.root.logger=INFO,console 的等号两边不能有空格
