HBase启动不了的一个原因处理

几天没有启动hbase，今天重新启动，却发现 HRegionServer没有启动，
到 region server 查看 jps，里面只有HQuorumPeer，没有 HRegionServer。
于是就单独启动:

hbase-daemon.sh --config /usr/local/hbase/hbase-conf start regionserver

看到日志:
/usr/local/hbase/hbase-logs/hbase-root-regionserver-ub9001.out:

Exception in thread "regionserver60020" java.lang.NullPointerException
	at org.apache.hadoop.hbase.regionserver.HRegionServer.join(HRegionServer.java:1587)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.run(HRegionServer.java:757)
	at java.lang.Thread.run(Thread.java:619)

/usr/local/hbase/hbase-logs/hbase-root-regionserver-ub9001.log:

2012-07-31 08:22:57,498 INFO org.apache.hadoop.hbase.regionserver.HRegionServer: Attempting connect to Master server at ub9000,60000,1343694287558
2012-07-31 08:22:57,539 INFO org.apache.hadoop.hbase.regionserver.HRegionServer: Connected to master at ub9001/192.168.0.221:60020
2012-07-31 08:22:57,539 INFO org.apache.hadoop.hbase.regionserver.HRegionServer: Telling master at ub9000,60000,1343694287558 that we are up with port=60020, startcode=1343694176934
2012-07-31 08:22:57,545 FATAL org.apache.hadoop.hbase.regionserver.HRegionServer: Master rejected startup because clock is out of sync
org.apache.hadoop.hbase.ClockOutOfSyncException: org.apache.hadoop.hbase.ClockOutOfSyncException: Server ub9001,60020,1343694176934 has been rejected; Reported time is too far out of sync with master.  Time difference of 410865ms > max allowed of 180000ms
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
	at org.apache.hadoop.ipc.RemoteException.instantiateException(RemoteException.java:95)
	at org.apache.hadoop.ipc.RemoteException.unwrapRemoteException(RemoteException.java:79)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.reportForDuty(HRegionServer.java:1676)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.run(HRegionServer.java:634)
	at java.lang.Thread.run(Thread.java:619)

才知道原来时间对不上.
同时在几个机器上校正时间:

date -s 08:42:00

最后重启:

hbase-daemon.sh --config /usr/local/hbase/hbase-conf start regionserver

2012-07-31 08:40:43,827 INFO org.apache.hadoop.ipc.HBaseServer: IPC Server Responder: starting
2012-07-31 08:40:43,828 INFO org.apache.hadoop.ipc.HBaseServer: IPC Server listener on 60020: starting

【成功截图】
hbase主控节点 -- HMaster

hbase 存储节点--HRegionServer


停止HBase