Hello, Although the namenode is running properly I can see the below shown warning in the log file.Could anyone tell me its meaning????
2011-11-29 01:42:30,582 WARN org.apache.hadoop.security.ShellBasedUnixGroupsMapping: got exception trying to get groups for user webuser org.apache.hadoop.util.Shell$ExitCodeException: id: webuser: No such user at org.apache.hadoop.util.Shell.runCommand(Shell.java:255) at org.apache.hadoop.util.Shell.run(Shell.java:182) at org.apache.hadoop.util.Shell$ShellCommandExecutor.execute(Shell.java:375) at org.apache.hadoop.util.Shell.execCommand(Shell.java:461) at org.apache.hadoop.util.Shell.execCommand(Shell.java:444) at org.apache.hadoop.security.ShellBasedUnixGroupsMapping.getUnixGroups(ShellBasedUnixGroupsMapping.java:68) at org.apache.hadoop.security.ShellBasedUnixGroupsMapping.getGroups(ShellBasedUnixGroupsMapping.java:45) at org.apache.hadoop.security.Groups.getGroups(Groups.java:79) at org.apache.hadoop.security.UserGroupInformation.getGroupNames(UserGroupInformation.java:966) at org.apache.hadoop.hdfs.server.namenode.FSPermissionChecker.<init>(FSPermissionChecker.java:50) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkPermission(FSNamesystem.java:5160) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.checkTraverse(FSNamesystem.java:5143) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.getFileInfo(FSNamesystem.java:1992) at org.apache.hadoop.hdfs.server.namenode.NameNode.getFileInfo(NameNode.java:837) 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.ipc.RPC$Server.call(RPC.java:563) at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1388) at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1384) at java.security.AccessController.doPrivileged(Native Method) at javax.security.auth.Subject.doAs(Subject.java:396) at org.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1059) at org.apache.hadoop.ipc.Server$Handler.run(Server.java:1382) 2011-11-29 01:44:59,571 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Roll Edit Log from 127.0.0.1 2011-11-29 01:44:59,572 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Number of transactions: 0 Total time for transactions(ms): 0Number of transactions batched in Syncs: 0 Number of syncs: 0 SyncTimes(ms): 0 2011-11-29 01:45:02,416 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Roll FSImage from 127.0.0.1 2011-11-29 01:45:02,416 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Number of transactions: 0 Total time for transactions(ms): 0Number of transactions batched in Syncs: 0 Number of syncs: 1 SyncTimes(ms): 109 Regards, Mohammad Tariq