2.5. Restore the HBase Configuration

If you have installed HBase, you may need to restore a configuration to its pre-HA state.

To check if your current HBase configuration needs to be restored, on the Ambari Server host:
```
/var/lib/ambari-server/resources/scripts/configs.sh -u $AMBARI_USER -p $AMBARI_PW -port $AMBARI_PORT get localhost $CLUSTER_NAME hbase-site
```
Where the environment variables you set up before substitute for the variable names.
Look for the configuration property hbase.rootdir. If the value is set to the NameService ID you set up using the Enable NameNode HA wizard, you need to revert the hbase-site configuration set up back to non-HA values. If it points instead to a specific NameNode host, it does not need to be rolled back and you can go on to Delete ZK Failover Controllers.
For example:
```
"hbase.rootdir":"hdfs://name-service-id:8020/apps/hbase/data"
The hbase.rootdir property points to the NameService ID and the value needs to be rolled back

"hbase.rootdir":"hdfs://nn01.mycompany.com:8020/apps/hbase/data"
The hbase.rootdir property points to a specific NameNode host and not a NameService ID. This does not need to be rolled back.
```
If you need to roll back the hbase.rootdir value, on the Ambari Server host, use the config.sh script to make the necessary change:
```
/var/lib/ambari-server/resources/scripts/configs.sh -u $AMBARI_USER -p $AMBARI_PW -port $AMBARI_PORT set localhost $CLUSTER_NAME hbase-site hbase.rootdir hdfs://${NAMENODE_HOSTNAME}:8020/apps/hbase/data
```
Where the environment variables you set up before substitute for the variable names.
Verify that the hbase.rootdir property has been restored properly. On the Ambari Server host:
```
/var/lib/ambari-server/resources/scripts/configs.sh -u $AMBARI_USER -p $AMBARI_PW -port $AMBARI_PORT get localhost $CLUSTER_NAME hbase-site
```
The hbase.rootdir property should now be set to the NameNode hostname, not the NameService ID.

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