Back up an HBase cluster - E-MapReduce - Alibaba Cloud Documentation Center

This topic describes how to back up an E-MapReduce (EMR) HBase cluster.

Prerequisites

Two Hadoop clusters are created, and the HBase and ZooKeeper services are added to the clusters. For more information, see Create a cluster.

Procedure

Log on to the master node of the cluster by using SSH.
For more information, see Connect to the master node of an EMR cluster in SSH mode.

Create a table and add data to the table.

Enable HBase Shell.
```
hbase shell
```
Create a table.
```
create 'test','cf'
```

Add data to the table.

put 'test','a','cf:c1',1
put 'test','a','cf:c2',2
put 'test','b','cf:c1',3
put 'test','b','cf:c2',4
put 'test','c','cf:c1',5
put 'test','c','cf:c2',6

Exit HBase Shell.
```
exit
```

Create a snapshot and query snapshot information.

Create a snapshot.

hbase snapshot create -n test_snapshot -t test

Enable HBase Shell.
```
hbase shell
```

Query snapshot information.

list_snapshots

The following information is returned:

SNAPSHOT                                           TABLE + CREATION TIME
 test_snapshot                                     test (Tue Aug 18 14:35:28 +0800 2020)
1 row(s) in 0.2450 seconds

=> ["test_snapshot"]

Exit HBase Shell.
```
exit
```

Export the created snapshot to OSS.

hbase org.apache.hadoop.hbase.snapshot.ExportSnapshot -snapshot test_snapshot -copy-to oss://$accessKeyId:$accessKeySecret@$bucket.oss-cn-hangzhou-internal.aliyuncs.com/hbase/snapshot/test

Note Use the internal endpoint to access OSS.

Log on to the other cluster by using SSH.

Export the snapshot from OSS.

hbase org.apache.hadoop.hbase.snapshot.ExportSnapshot -snapshot test_snapshot -copy-from oss://$accessKeyId:$accessKeySecret@$bucket.oss-cn-hangzhou-internal.aliyuncs.com/hbase/snapshot/test -copy-to /hbase/

Restore data from the snapshot and view data in the restored table.

Enable HBase Shell.
```
hbase shell
```
Restore data from the snapshot.
```
restore_snapshot 'test_snapshot'
```

View data in the restored table.

scan 'test'

The following information is returned:

ROW                     COLUMN+CELL
 a                      column=cf:c1, timestamp=1472992081375, value=1
 a                      column=cf:c2, timestamp=1472992090434, value=2
 b                      column=cf:c1, timestamp=1472992104339, value=3
 b                      column=cf:c2, timestamp=1472992099611, value=4
 c                      column=cf:c1, timestamp=1472992112657, value=5
 c                      column=cf:c2, timestamp=1472992118964, value=6
3 row(s) in 0.0540 seconds

Create a table based on the snapshot and view data in the table.

Create a table based on the snapshot.
```
clone_snapshot 'test_snapshot','test_2'
```

View data in the table.

scan 'test_2'

The following information is returned:

ROW                     COLUMN+CELL
 a                      column=cf:c1, timestamp=1472992081375, value=1
 a                      column=cf:c2, timestamp=1472992090434, value=2
 b                      column=cf:c1, timestamp=1472992104339, value=3
 b                      column=cf:c2, timestamp=1472992099611, value=4
 c                      column=cf:c1, timestamp=1472992112657, value=5
 c                      column=cf:c2, timestamp=1472992118964, value=6
3 row(s) in 0.0540 seconds