HBase Snapshot 相关命令学习

1. clone_snapshot

根据快照恢复一个宽表，恢复过程不涉及数据移动，可以在秒级完成。

hbase(main):003:0> help 'clone_snapshot'
Create a new table by cloning the snapshot content.
There're no copies of data involved.
And writing on the newly created table will not influence the snapshot data.

Examples:
  hbase> clone_snapshot 'snapshotName', 'tableName'
  hbase> clone_snapshot 'snapshotName', 'namespace:tableName'

Following command will restore all acl from origin snapshot table into the
newly created table.

  hbase> clone_snapshot 'snapshotName', 'namespace:tableName', {RESTORE_ACL=>true}

2. delete_all_snapshot

删除所有快照，支持正则。

hbase(main):004:0> help 'delete_all_snapshot'
Delete all of the snapshots matching the given regex. Examples:

  hbase> delete_all_snapshot 's.*'

3. delete_snapshot

删除指定快照。

hbase(main):005:0> help 'delete_snapshot'
Delete a specified snapshot. Examples:

  hbase> delete_snapshot 'snapshotName',

4. list_snapshots

列出所有的快照，支持*匹配。

hbase(main):006:0> help 'list_snapshots'
List all snapshots taken (by printing the names and relative information).
Optional regular expression parameter could be used to filter the output
by snapshot name.

Examples:
  hbase> list_snapshots
  hbase> list_snapshots 'abc.*'

5. restore_snapshot

用于恢复指定快照，恢复过程会替代原有数据，将表恢复到快照点，快照之后的所有更新将会丢失。表必须disable.

hbase(main):007:0> help 'restore_snapshot'
Restore a specified snapshot.
The restore will replace the content of the original table,
bringing back the content to the snapshot state.
The table must be disabled.

Examples:
  hbase> restore_snapshot 'snapshotName'

Following command will restore all acl from snapshot into the table.

  hbase> restore_snapshot 'snapshotName', {RESTORE_ACL=>true}

6. snapshot

为表打一个快照，但并不涉及数据移动。

hbase(main):008:0> help 'snapshot'
Take a snapshot of specified table. Examples:

  hbase> snapshot 'sourceTable', 'snapshotName'
  hbase> snapshot 'namespace:sourceTable', 'snapshotName', {SKIP_FLUSH => true}

7. snapshot_all

为所有的表创建快照，快照名按系统规则生成，大约是这个样子：dalishen_ns_sep_test_zpb-ru-20191219

hbase(main):009:0> help 'snapshot_all'
List all tables and take snapshot .
Optional regular expression parameter could be used to filter the output
by table name.

Examples:
  hbase> snapshot_all
  hbase> snapshot_all 'abc.*'

8. snapshot_restore

暂时不明

hbase(main):010:0> help 'snapshot_restore'
Use snapshot to restore tables.
Date parameter (in the form YYYY-mm-dd) is used to filter the snapshots

Examples:
  hbase> snapshot_restore '2014-12-09'

9. Snapshot 两阶段提交：1.acquired 2.reached/abort

原理：zk 3节点保证。

ls /${hbaserootdir}/online-snapshot
./acquired
./abort
./reached