Hadoop HA 搭建hbase啟動時只有HMaster起來，HRegionServer沒有起來

檢視報錯資訊為：

2019-08-31 19:17:14,212 ERROR [main] regionserver.HRegionServer: Failed construction RegionServer
java.lang.IllegalArgumentException: java.net.UnknownHostException: mycluster
	at org.apache.hadoop.security.SecurityUtil.buildTokenService(SecurityUtil.java:417)
	at org.apache.hadoop.hdfs.NameNodeProxiesClient.createProxyWithClientProtocol(NameNodeProxiesClient.java:132)
	at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:351)
	at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:285)
	at org.apache.hadoop.hdfs.DistributedFileSystem.initialize(DistributedFileSystem.java:160)
	at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:2812)
	at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:100)
	at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:2849)
	at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2831)
	at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:389)
	at org.apache.hadoop.fs.Path.getFileSystem(Path.java:356)
	at org.apache.hadoop.hbase.util.CommonFSUtils.getRootDir(CommonFSUtils.java:362)
	at org.apache.hadoop.hbase.util.CommonFSUtils.isValidWALRootDir(CommonFSUtils.java:412)
	at org.apache.hadoop.hbase.util.CommonFSUtils.getWALRootDir(CommonFSUtils.java:388)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.initializeFileSystem(HRegionServer.java:723)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.<init>(HRegionServer.java:629)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.constructRegionServer(HRegionServer.java:3035)
	at org.apache.hadoop.hbase.regionserver.HRegionServerCommandLine.start(HRegionServerCommandLine.java:63)
	at org.apache.hadoop.hbase.regionserver.HRegionServerCommandLine.run(HRegionServerCommandLine.java:87)
	at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:76)
	at org.apache.hadoop.hbase.util.ServerCommandLine.doMain(ServerCommandLine.java:149)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.main(HRegionServer.java:3053)
Caused by: java.net.UnknownHostException: mycluster
	... 26 more
2019-08-31 19:17:14,217 ERROR [main] regionserver.HRegionServerCommandLine: Region server exiting
java.lang.RuntimeException: Failed construction of Regionserver: class org.apache.hadoop.hbase.regionserver.HRegionServer
	at org.apache.hadoop.hbase.regionserver.HRegionServer.constructRegionServer(HRegionServer.java:3038)
	at org.apache.hadoop.hbase.regionserver.HRegionServerCommandLine.start(HRegionServerCommandLine.java:63)
	at org.apache.hadoop.hbase.regionserver.HRegionServerCommandLine.run(HRegionServerCommandLine.java:87)
	at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:76)
	at org.apache.hadoop.hbase.util.ServerCommandLine.doMain(ServerCommandLine.java:149)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.main(HRegionServer.java:3053)
Caused by: java.lang.reflect.InvocationTargetException
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.constructRegionServer(HRegionServer.java:3035)
	... 5 more
Caused by: java.lang.IllegalArgumentException: java.net.UnknownHostException: mycluster
	at org.apache.hadoop.security.SecurityUtil.buildTokenService(SecurityUtil.java:417)
	at org.apache.hadoop.hdfs.NameNodeProxiesClient.createProxyWithClientProtocol(NameNodeProxiesClient.java:132)
	at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:351)
	at org.apache.hadoop.hdfs.DFSClient.<init>(DFSClient.java:285)
	at org.apache.hadoop.hdfs.DistributedFileSystem.initialize(DistributedFileSystem.java:160)
	at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:2812)
	at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:100)
	at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:2849)
	at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2831)
	at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:389)
	at org.apache.hadoop.fs.Path.getFileSystem(Path.java:356)
	at org.apache.hadoop.hbase.util.CommonFSUtils.getRootDir(CommonFSUtils.java:362)
	at org.apache.hadoop.hbase.util.CommonFSUtils.isValidWALRootDir(CommonFSUtils.java:412)
	at org.apache.hadoop.hbase.util.CommonFSUtils.getWALRootDir(CommonFSUtils.java:388)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.initializeFileSystem(HRegionServer.java:723)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.<init>(HRegionServer.java:629)
	... 10 more
Caused by: java.net.UnknownHostException: mycluster

　　由於無法找到mycluster

解決方法：

將hadoop/etc/中的 core-site.xml和hdfs-site.xml 複製到hbase的conf目錄下，啟動hbase就