如果是新搭的CDH 集群并使用默认的kudu设置, 使用spark /java 连接kudu时候，一般都会碰到此类异常。
程序：
val masteraddr = "kudumasterip:7051"
//创建kudu的数据库链接
val client = new KuduClient.KuduClientBuilder(masteraddr).build
//打开表
val table = client.openTable("impala::testdb.PERSON")
异常信息：
java.lang.RuntimeException: Could not deserialize the response, incompatible RPC? Error is: step
at org.apache.kudu.client.KuduRpc.readProtobuf(KuduRpc.java:383)
at org.apache.kudu.client.Negotiator.parseSaslMsgResponse(Negotiator.java:282)
at org.apache.kudu.client.Negotiator.handleResponse(Negotiator.java:235)
at org.apache.kudu.client.Negotiator.messageReceived(Negotiator.java:229)
at org.apache.kudu.client.shaded.org.jboss.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:70)
at org.apache.kudu.client.shaded.org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564)
at org.apache.kudu.client.shaded.org.jboss.netty.channel.DefaultChannelPipeline$DefaultChannelHandlerContext.sendUpstream(DefaultChannelPipeline.java:791)
at org.apache.kudu.client.shaded.org.jboss.netty.handler.timeout.ReadTimeoutHandler.messageReceived(ReadTimeoutHandler.java:184)
at org.apache.kudu.client.shaded.org.jboss.netty.channel.SimpleChannelUpstreamHandler.handleUpstream(SimpleChannelUpstreamHandler.java:70)
at org.apache.kudu.client.shaded.org.jboss.netty.channel.DefaultChannelPipeline.sendUpstream(DefaultChannelPipeline.java:564)
at org.apache.kudu.client.shaded.org.jboss.netty.channel.DefaultChannelPipeline$DefaultChannelHandlerContext.sendUpstream(DefaultChannelPipeline.java:791)
解决方法：
在CDH 页面上设置kudu 高级配置项：
-rpc_encryption=disabled
-rpc_authentication=disabled
-trusted_subnets=0.0.0.0/0