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  === Redo Logs ===
  
- It is possible that, when running the HBase migration command, the migration 
will fail because of "unrecovered redo logs."  Redo logs are generated every 
time HBase is started, and under normal circumstances they are removed when 
HBase is stopped.  However, if you have ever stopped HBase in some atypical way 
(for example, using {{{kill -9}}}), these redo logs will persist in Hadoop DFS. 
 To see if you have any unrecovered redo logs, stop any currently-running 
instances of HBase and enter: {{{{$HADOOP_HOME}/bin/hadoop dfs -ls /hbase}}}.  
All existing redo logs will be in this directory.  Redo log directories can be 
removed using the dfs {{{-rmr}}} option.  WARNING: redo logs are the only way 
to recover any data entered before HBase was improperly stopped.  Removing redo 
logs with file size greater than zero may result in irreversible data loss.
+ It is possible that, when running the HBase migration command, the migration 
will fail because of "unrecovered redo logs."  Redo logs are generated every 
time HBase is started, and under normal circumstances they are removed when 
HBase is stopped cleanly.  However, if you have ever stopped HBase in some 
atypical way (for example, using {{{kill -9}}}), these redo logs will persist 
in Hadoop DFS.  To see if you have any unrecovered redo logs, stop any 
currently-running instances of HBase and enter: {{{{$HADOOP_HOME}/bin/hadoop 
dfs -ls /hbase}}}.  All existing redo logs will be in this directory.  Redo log 
directories can be removed using dfs {{{-rm}}} option.  WARNING: redo logs are 
the only way to recover any data entered before HBase was improperly stopped.  
Removing redo logs with file size greater than zero may result in irreversible 
data loss.
  

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