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https://issues.apache.org/jira/browse/HBASE-11620?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14098152#comment-14098152
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ramkrishna.s.vasudevan commented on HBASE-11620:
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bq.Related to this, should not we also write the CellCodec that we use in the
WAL header. Right now, the codec comes from the configuration which means that
you cannot read back the WAL files if you change the codec
+1. Would be really helpful.
> Record the class name of Writer in WAL header so that only proper Reader can
> open the WAL file
> ----------------------------------------------------------------------------------------------
>
> Key: HBASE-11620
> URL: https://issues.apache.org/jira/browse/HBASE-11620
> Project: HBase
> Issue Type: Bug
> Affects Versions: 0.98.4
> Reporter: Ted Yu
> Assignee: Ted Yu
> Priority: Critical
> Fix For: 0.99.0, 0.98.5, 2.0.0
>
> Attachments: 11620-0.98-v6.txt, 11620-0.98-v7.txt, 11620-v1.txt,
> 11620-v2.txt, 11620-v3.txt, 11620-v4.txt, 11620-v5.txt, 11620-v6.txt,
> 11620-v6.txt, 11620-v7.txt
>
>
> Reported by Kiran in this thread: "HBase file encryption, inconsistencies
> observed and data loss"
> After step 4 ( i.e disabling of WAL encryption, removing
> SecureProtobufReader/Writer and restart), read of encrypted WAL fails mainly
> due to EOF exception at Basedecoder. This is not considered as error and
> these WAL are being moved to /oldWALs.
> Following is observed in log files:
> {code}
> 2014-07-30 19:44:29,254 INFO [RS_LOG_REPLAY_OPS-HOST-16:15264-1]
> wal.HLogSplitter: Splitting hlog:
> hdfs://HOST-16:18020/hbase/WALs/HOST-16,15264,1406725441997-splitting/HOST-16%2C15264%2C1406725441997.1406725444017,
> length=172
> 2014-07-30 19:44:29,254 INFO [RS_LOG_REPLAY_OPS-HOST-16:15264-1]
> wal.HLogSplitter: DistributedLogReplay = false
> 2014-07-30 19:44:29,313 INFO [RS_LOG_REPLAY_OPS-HOST-16:15264-1]
> util.FSHDFSUtils: Recovering lease on dfs file
> hdfs://HOST-16:18020/hbase/WALs/HOST-16,15264,1406725441997-splitting/HOST-16%2C15264%2C1406725441997.1406725444017
> 2014-07-30 19:44:29,315 INFO [RS_LOG_REPLAY_OPS-HOST-16:15264-1]
> util.FSHDFSUtils: recoverLease=true, attempt=0 on
> file=hdfs://HOST-16:18020/hbase/WALs/HOST-16,15264,1406725441997-splitting/HOST-16%2C15264%2C1406725441997.1406725444017
> after 1ms
> 2014-07-30 19:44:29,429 DEBUG [RS_LOG_REPLAY_OPS-HOST-16:15264-1-Writer-0]
> wal.HLogSplitter: Writer thread
> Thread[RS_LOG_REPLAY_OPS-HOST-16:15264-1-Writer-0,5,main]: starting
> 2014-07-30 19:44:29,429 DEBUG [RS_LOG_REPLAY_OPS-HOST-16:15264-1-Writer-1]
> wal.HLogSplitter: Writer thread
> Thread[RS_LOG_REPLAY_OPS-HOST-16:15264-1-Writer-1,5,main]: starting
> 2014-07-30 19:44:29,430 DEBUG [RS_LOG_REPLAY_OPS-HOST-16:15264-1-Writer-2]
> wal.HLogSplitter: Writer thread
> Thread[RS_LOG_REPLAY_OPS-HOST-16:15264-1-Writer-2,5,main]: starting
> 2014-07-30 19:44:29,591 ERROR [RS_LOG_REPLAY_OPS-HOST-16:15264-1]
> codec.BaseDecoder: Partial cell read caused by EOF: java.io.IOException:
> Premature EOF from inputStream
> 2014-07-30 19:44:29,592 INFO [RS_LOG_REPLAY_OPS-HOST-16:15264-1]
> wal.HLogSplitter: Finishing writing output logs and closing down.
> 2014-07-30 19:44:29,592 INFO [RS_LOG_REPLAY_OPS-HOST-16:15264-1]
> wal.HLogSplitter: Waiting for split writer threads to finish
> 2014-07-30 19:44:29,592 INFO [RS_LOG_REPLAY_OPS-HOST-16:15264-1]
> wal.HLogSplitter: Split writers finished
> 2014-07-30 19:44:29,592 INFO [RS_LOG_REPLAY_OPS-HOST-16:15264-1]
> wal.HLogSplitter: Processed 0 edits across 0 regions; log
> file=hdfs://HOST-16:18020/hbase/WALs/HOST-16,15264,1406725441997-splitting/HOST-16%2C15264%2C1406725441997.1406725444017
> is corrupted = false progress failed = false
> {code}
> To fix this, we need to propagate EOF exception to HLogSplitter. Any
> suggestions on the fix?
> -------- (end of quote from Kiran)
> In BaseDecoder#rethrowEofException() :
> {code}
> if (!isEof) throw ioEx;
> LOG.error("Partial cell read caused by EOF: " + ioEx);
> EOFException eofEx = new EOFException("Partial cell read");
> eofEx.initCause(ioEx);
> throw eofEx;
> {code}
> throwing EOFException would not propagate the "Partial cell read" condition
> to HLogSplitter which doesn't treat EOFException as an error.
> I think IOException should be thrown above - HLogSplitter#getNextLogLine()
> would translate the IOEx to CorruptedLogFileException.
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