UnknownScannerException on Short Job

Hi Everyone,

I have been having a lot of issues reading from a HBase tables, I keep getting UnknownScannerException's when I try to iterate over a table.

I read on this forum that this is a result of leases timing out by mappers taking too long before calling next(). I noticed however that this issue is not a result of Mapper itself since even when running a Map function which only contains a return statement, it still throws the same exception. When I run the same program, on the same table with a local job tracker, it seems to work. It does however work distributed on a small table.

Any suggestions on the reasoning for why it works locally but not distributed?


The following is the exception that is being thrown:
org.apache.hadoop.hbase.UnknownScannerException: org.apache.hadoop.hbase.UnknownScannerException: -2478484392535468022
        at org.apache.hadoop.hbase.HRegionServer.close(HRegionServer.java:1482)
        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.ipc.HbaseRPC$Server.call(HbaseRPC.java:413)
        at org.apache.hadoop.ipc.Server$Handler.run(Server.java:910)

        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
        at org.apache.hadoop.hbase.RemoteExceptionHandler.decodeRemoteException(RemoteExceptionHandler.java:82)
        at org.apache.hadoop.hbase.HTable$ClientScanner.close(HTable.java:1169)
        at org.apache.hadoop.hbase.mapred.TableInputFormat$TableRecordReader.close(TableInputFormat.java:88)
        at org.apache.hadoop.mapred.MapTask$TrackedRecordReader.close(MapTask.java:155)
        at org.apache.hadoop.mapred.MapTask.run(MapTask.java:212)
        at org.apache.hadoop.mapred.TaskTracker$Child.main(TaskTracker.java:2071)