[Default-IPC-NioEventLoopGroup-1-1] WARN org.apache.hbase.thirdparty.io.netty.util.concurrent.DefaultPromise - An exception was thrown by org.apache.hadoop.hbase.ipc.NettyRpcConnection$2.operationComplete() java.lang.NullPointerException at org.apache.hadoop.hbase.security.SaslUtil.splitKerberosName(SaslUtil.java:69) at org.apache.hadoop.hbase.security.provider.GssSaslClientAuthenticationProvider.createClient(GssSaslClientAuthenticationProvider.java:64) at org.apache.hadoop.hbase.security.AbstractHBaseSaslRpcClient.<init>(AbstractHBaseSaslRpcClient.java:83) at org.apache.hadoop.hbase.security.NettyHBaseSaslRpcClient.<init>(NettyHBaseSaslRpcClient.java:47) at org.apache.hadoop.hbase.security.NettyHBaseSaslRpcClientHandler.<init>(NettyHBaseSaslRpcClientHandler.java:72) at org.apache.hadoop.hbase.ipc.NettyRpcConnection.saslNegotiate(NettyRpcConnection.java:207) at org.apache.hadoop.hbase.ipc.NettyRpcConnection.access$600(NettyRpcConnection.java:75) at org.apache.hadoop.hbase.ipc.NettyRpcConnection$2.operationComplete(NettyRpcConnection.java:287) at org.apache.hadoop.hbase.ipc.NettyRpcConnection$2.operationComplete(NettyRpcConnection.java:275) at org.apache.hbase.thirdparty.io.netty.util.concurrent.DefaultPromise.notifyListener0(DefaultPromise.java:578) at org.apache.hbase.thirdparty.io.netty.util.concurrent.DefaultPromise.notifyListeners0(DefaultPromise.java:571) at org.apache.hbase.thirdparty.io.netty.util.concurrent.DefaultPromise.notifyListenersNow(DefaultPromise.java:550) at org.apache.hbase.thirdparty.io.netty.util.concurrent.DefaultPromise.notifyListeners(DefaultPromise.java:491) at org.apache.hbase.thirdparty.io.netty.util.concurrent.DefaultPromise.setValue0(DefaultPromise.java:616) at org.apache.hbase.thirdparty.io.netty.util.concurrent.DefaultPromise.setSuccess0(DefaultPromise.java:605) at org.apache.hbase.thirdparty.io.netty.util.concurrent.DefaultPromise.trySuccess(DefaultPromise.java:104) at org.apache.hbase.thirdparty.io.netty.channel.DefaultChannelPromise.trySuccess(DefaultChannelPromise.java:84) at org.apache.hbase.thirdparty.io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.fulfillConnectPromise(AbstractNioChannel.java:300) at org.apache.hbase.thirdparty.io.netty.channel.nio.AbstractNioChannel$AbstractNioUnsafe.finishConnect(AbstractNioChannel.java:335) at org.apache.hbase.thirdparty.io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:707) at org.apache.hbase.thirdparty.io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:655) at org.apache.hbase.thirdparty.io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:581) at org.apache.hbase.thirdparty.io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:493) at org.apache.hbase.thirdparty.io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:989) at org.apache.hbase.thirdparty.io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) at org.apache.hbase.thirdparty.io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)   could anyone please help me with the above highlighted Exception? what could be the reason? ... View more