Spark 写入带有Kerberos认证的HBase在Yarn-Cluster模式下运行报错

先粘出来报错信息

javax.security.sasl.SaslException: GSS initiate failed [Caused by GSSException: No valid credentials provided (Mechanism level: Failed to find any Kerberos tgt)]
	at com.sun.security.sasl.gsskerb.GssKrb5Client.evaluateChallenge(GssKrb5Client.java:211)
	at org.apache.hadoop.hbase.security.HBaseSaslRpcClient.saslConnect(HBaseSaslRpcClient.java:179)
	at org.apache.hadoop.hbase.ipc.RpcClientImpl$Connection.setupSaslConnection(RpcClientImpl.java:642)
	at org.apache.hadoop.hbase.ipc.RpcClientImpl$Connection.access$600(RpcClientImpl.java:166)
	at org.apache.hadoop.hbase.ipc.RpcClientImpl$Connection$2.run(RpcClientImpl.java:769)
	at org.apache.hadoop.hbase.ipc.RpcClientImpl$Connection$2.run(RpcClientImpl.java:766)
	at java.security.AccessController.doPrivileged(Native Method)
	at javax.security.auth.Subject.doAs(Subject.java:422)
	at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1866)
	at org.apache.hadoop.hbase.ipc.RpcClientImpl$Connection.setupIOstreams(RpcClientImpl.java:766)
	at org.apache.hadoop.hbase.ipc.RpcClientImpl$Connection.writeRequest(RpcClientImpl.java:920)
	at org.apache.hadoop.hbase.ipc.RpcClientImpl$Connection.tracedWriteRequest(RpcClientImpl.java:889)
	at org.apache.hadoop.hbase.ipc.RpcClientImpl.call(RpcClientImpl.java:1222)
	at org.apache.hadoop.hbase.ipc.AbstractRpcClient.callBlockingMethod(AbstractRpcClient.java:213)
	at org.apache.hadoop.hbase.ipc.AbstractRpcClient$BlockingRpcChannelImplementation.callBlockingMethod(AbstractRpcClient.java:287)
	at org.apache.hadoop.hbase.protobuf.generated.ClientProtos$ClientService$BlockingStub.scan(ClientProtos.java:32651)
	at org.apache.hadoop.hbase.client.ClientSmallScanner$SmallScannerCallable.call(ClientSmallScanner.java:201)
	at org.apache.hadoop.hbase.client.ClientSmallScanner$SmallScannerCallable.call(ClientSmallScanner.java:180)
	at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:200)
	at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas$RetryingRPC.call(ScannerCallableWithReplicas.java:346)
	at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas$RetryingRPC.call(ScannerCallableWithReplicas.java:320)
	at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithRetries(RpcRetryingCaller.java:126)
	at org.apache.hadoop.hbase.client.ResultBoundedCompletionService$QueueingFuture.run(ResultBoundedCompletionService.java:64)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:748)
Caused by: GSSException: No valid credentials provided (Mechanism level: Failed to find any Kerberos tgt)
	at sun.security.jgss.krb5.Krb5InitCredential.getInstance(Krb5InitCredential.java:147)
	at sun.security.jgss.krb5.Krb5MechFactory.getCredentialElement(Krb5MechFactory.java:122)
	at sun.security.jgss.krb5.Krb5MechFactory.getMechanismContext(Krb5MechFactory.java:187)
	at sun.security.jgss.GSSManagerImpl.getMechanismContext(GSSManagerImpl.java:224)
	at sun.security.jgss.GSSContextImpl.initSecContext(GSSContextImpl.java:212)
	at sun.security.jgss.GSSContextImpl.initSecContext(GSSContextImpl.java:179)
	at com.sun.security.sasl.gsskerb.GssKrb5Client.evaluateChallenge(GssKrb5Client.java:192)
	... 25 more
19/09/26 14:47:42 WARN AbstractRpcClient: Exception encountered while connecting to the server : javax.security.sasl.SaslException: GSS initiate failed [Caused by GSSException: No valid credentials provided (Mechanism level: Failed to find any Kerberos tgt)]
19/09/26 14:47:42 ERROR AbstractRpcClient: SASL authentication failed. The most likely cause is missing or invalid credentials. Consider 'kinit'.

这是我在测试Spark写入带有Kerberos认证的HBase时出现的BUG
具体代码就不粘出来了，当时场景就是spark代码打Jar后放到linux上执行，local和Yarn-Client模式下均可正常写入，但是使用Yarn-Cluster模式执行的时候就一直不结束，不出执行状态结果。后来去查看日志发现上述异常
错误原因：cluster模式较之local和client来说，cluster是把代码放在了集群的Driver端，连接HBase的方式略有不同
解决办法：

这里需特别注意，cluster模式下测试连接HBase时一定要使用UGI的doAs方法，把连接写在里面，这样就可以避免连接不上报GSS错误。

部分代码：

val ugi = UserGroupInformation.loginUserFromKeytabbAndReturnUGI(principal,kaytab_path)
..................
ugi.doAs(new PrivilegeAction[Unit] {
	....................
})