Hi, You may have noticed this: https://builds.apache.org/view/G-L/view/HBase/job/HBase-TRUNK-security/161/testReport/org.apache.hadoop.hbase.coprocessor/TestRowProcessorEndpoint/org_apache_hadoop_hbase_coprocessor_TestRowProcessorEndpoint/
I reproduced it on MacBook. Here is the tail of test output: 2012-04-07 08:45:17,801 WARN [RegionServer:0;192.168.0.17,59758,1333813404805] regionserver.HRegionServer(1813): Unable to connect to master. Retrying. Error was: java.io.IOException: Call to /192.168.0.17:59756 failed on local exception: java.io.EOFException at org.apache.hadoop.hbase.ipc.HBaseClient.wrapException(HBaseClient.java:945) at org.apache.hadoop.hbase.ipc.HBaseClient.call(HBaseClient.java:914) at org.apache.hadoop.hbase.ipc.SecureRpcEngine$Invoker.invoke(SecureRpcEngine.java:164) at $Proxy18.getProtocolVersion(Unknown Source) at org.apache.hadoop.hbase.ipc.SecureRpcEngine.getProxy(SecureRpcEngine.java:208) at org.apache.hadoop.hbase.ipc.HBaseRPC.getProxy(HBaseRPC.java:305) at org.apache.hadoop.hbase.ipc.HBaseRPC.getProxy(HBaseRPC.java:282) at org.apache.hadoop.hbase.ipc.HBaseRPC.getProxy(HBaseRPC.java:334) at org.apache.hadoop.hbase.ipc.HBaseRPC.waitForProxy(HBaseRPC.java:238) at org.apache.hadoop.hbase.regionserver.HRegionServer.getMaster(HRegionServer.java:1799) at org.apache.hadoop.hbase.regionserver.HRegionServer.reportForDuty(HRegionServer.java:1845) at org.apache.hadoop.hbase.regionserver.HRegionServer.run(HRegionServer.java:672) at org.apache.hadoop.hbase.MiniHBaseCluster$MiniHBaseClusterRegionServer.runRegionServer(MiniHBaseCluster.java:140) at org.apache.hadoop.hbase.MiniHBaseCluster$MiniHBaseClusterRegionServer.access$000(MiniHBaseCluster.java:93) at org.apache.hadoop.hbase.MiniHBaseCluster$MiniHBaseClusterRegionServer$1.run(MiniHBaseCluster.java:124) at java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:337) at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1075) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.hadoop.hbase.util.Methods.call(Methods.java:41) at org.apache.hadoop.hbase.security.User.call(User.java:617) at org.apache.hadoop.hbase.security.User.access$700(User.java:54) at org.apache.hadoop.hbase.security.User$SecureHadoopUser.runAs(User.java:457) at org.apache.hadoop.hbase.MiniHBaseCluster$MiniHBaseClusterRegionServer.run(MiniHBaseCluster.java:122) at java.lang.Thread.run(Thread.java:680) Caused by: java.io.EOFException at java.io.DataInputStream.readInt(DataInputStream.java:375) at org.apache.hadoop.hbase.ipc.SecureClient$SecureConnection.receiveResponse(SecureClient.java:344) at org.apache.hadoop.hbase.ipc.HBaseClient$Connection.run(HBaseClient.java:507) 2012-04-07 08:45:18,002 INFO [RegionServer:0;192.168.0.17,59758,1333813404805] regionserver.HRegionServer(1794): Attempting connect to Master server at 192.168.0.17,59756,1333813402649 2012-04-07 08:45:18,223 WARN [IPC Reader 3 on port 59756] ipc.HBaseServer$Listener(723): IPC Server listener on 59756: readAndProcess threw exception java.lang.NullPointerException. Count of bytes read: 0 java.lang.NullPointerException at org.apache.hadoop.hbase.io.HbaseObjectWritable.readObject(HbaseObjectWritable.java:605) at org.apache.hadoop.hbase.ipc.Invocation.readFields(Invocation.java:127) at org.apache.hadoop.hbase.ipc.SecureServer$SecureConnection.processData(SecureServer.java:597) at org.apache.hadoop.hbase.ipc.SecureServer$SecureConnection.processOneRpc(SecureServer.java:575) at org.apache.hadoop.hbase.ipc.SecureServer$SecureConnection.readAndProcess(SecureServer.java:474) at org.apache.hadoop.hbase.ipc.HBaseServer$Listener.doRead(HBaseServer.java:719) at org.apache.hadoop.hbase.ipc.HBaseServer$Listener$Reader.doRunLoop(HBaseServer.java:510) at org.apache.hadoop.hbase.ipc.HBaseServer$Listener$Reader.run(HBaseServer.java:485) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:680) FYI
