Details

    • Type: Bug
    • Status: Closed
    • Priority: Blocker
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: 0.98.0, 0.94.7, 0.95.1
    • Component/s: None
    • Labels:
      None
    • Hadoop Flags:
      Incompatible change, Reviewed
    • Release Note:
      Hide
      In order to avoid name collision with hdfs snapshot, ".snapshot" under HBase root directory must be renamed as ".hbase-snapshot" before deployment of 0.94.7 or later release is started.

      Don't do rolling upgrade between 0.94.6.1 and 0.94.7 if there're on-going snapshots activities.
      Sequence of actions should be:

      1. make sure all on-going snapshots activities have completed
      2. shutdown all the masters
      3. rename ".snapshot" under HBase root directory as ".hbase-snapshot"
      4. upgrade the masters to 0.94.7+ release (You now can perform clone or restore, but not taking snapshots)
      5. upgrade the region servers
      (You should not take snapshots until all the regions server are aligned to 0.94.7+ release)

      If you take a snapshot during the RS upgrades nothing critical happens. The ".snapshot" folder would appear again and the snapshot will fail since half of the data will be in ".hbase-snapshot" and the other half in ".snapshot"
      Show
      In order to avoid name collision with hdfs snapshot, ".snapshot" under HBase root directory must be renamed as ".hbase-snapshot" before deployment of 0.94.7 or later release is started. Don't do rolling upgrade between 0.94.6.1 and 0.94.7 if there're on-going snapshots activities. Sequence of actions should be: 1. make sure all on-going snapshots activities have completed 2. shutdown all the masters 3. rename ".snapshot" under HBase root directory as ".hbase-snapshot" 4. upgrade the masters to 0.94.7+ release (You now can perform clone or restore, but not taking snapshots) 5. upgrade the region servers (You should not take snapshots until all the regions server are aligned to 0.94.7+ release) If you take a snapshot during the RS upgrades nothing critical happens. The ".snapshot" folder would appear again and the snapshot will fail since half of the data will be in ".hbase-snapshot" and the other half in ".snapshot"

      Description

      Testing HBase Snapshot on top of Hadoop's Snapshot branch (http://svn.apache.org/viewvc/hadoop/common/branches/HDFS-2802/), we found that both features used '.snapshot' directory to store metadata.

      HDFS (built from HDFS-2802 branch) doesn't allow paths with .snapshot as a component

      From discussion on dev@hbase.apache.org, (see http://search-hadoop.com/m/kY6C3cXMs51), consensus was to rename '.snapshot' directory in HBase so that both features can co-exist smoothly.

        Attachments

        1. 8352-0.94-v1.txt
          7 kB
          Ted Yu
        2. 8352-trunk.txt
          7 kB
          Ted Yu
        3. 8352-trunk-v2.txt
          7 kB
          Ted Yu
        4. 8352-0.94-v2.txt
          8 kB
          Ted Yu
        5. 8352-trunk-v3.txt
          7 kB
          Ted Yu
        6. 8352-trunk-v4.txt
          10 kB
          Ted Yu
        7. 8352-trunk-v5.txt
          9 kB
          Ted Yu
        8. 8352-0.94-v3.txt
          10 kB
          Ted Yu
        9. 8352-trunk-v6.txt
          10 kB
          Ted Yu
        10. 8352-0.94-v4.txt
          10 kB
          Ted Yu

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              • Assignee:
                yuzhihong@gmail.com Ted Yu
                Reporter:
                yuzhihong@gmail.com Ted Yu
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                Dates

                • Created:
                  Updated:
                  Resolved: