Introduction

This blog details out the procedure to remove unwanted xs engine service from HANA topology. We have faced a situation where two xs-engine services added in the HANA database and one for them is not getting started.

System Details

• HANA 2.0 SPS03

Prerequisites

1. You are logged on to the system database and having a system privilege DATABASE ADMIN.
2. Make sure to take data backup of SystemDB.
3. The database is online.
4. Get the volume id, port number, and check-in M_TOPOLOGY_TREE view.

SAP Notes/KBA

2679277 – HANA backup fails with error on orphaned volume in Multitenant Database

M_TOPOLOGY_TREE System View

Error details

1. Two xs-engine services added and one of them is not getting started.
2. Backup error–Backup is not possible because the service ‘xs-engine’ at <host: port> responsible for the volume ‘volume id’ has the wrong state ‘no’, Orphaned volume with the number ‘volume id’ found in the topology.

Backup Error Message

Note

We removed the SAP HANA Extended Application Services (SAP HANA XS) from the topology of our SAP HANA database because we do not use any applications that require SAP HANA XS.

Please do not remove the SAP HANA XS if there is an application running which uses the xs engine.

Execution

To solve this issue, we removed unwanted xs-engine from the topology.

Execute command “SELECT * FROM M_TOPOLOGY_TREE” to check-in the view of the topology tree and take a complete download on your desktop for further reference.

In the topology tree, we can find the volume id and port number of the service.

Execute command “SELECT * FROM M_VOLUMES” to check-in the assigned volume to the xs engine service port.

Once the volume of the xs engine service is verified also check the M_SERVICES view to confirm that there are no services associated with this volume.

Also, verify the size of the volume ID at the os level.

Removal of the service:

With the help of the steps mentioned above, we are now able to identify the service, port, and volume ID which needs to be removed.

In my case, the port number is 33007 and the volume ID is 3:2.

So let’s remove the service and volume using the below commands.

Make sure to execute these commands from SYSTEM DB.

Remove Service:-

ALTER SYSTEM ALTER CONFIGURATION (‘topology.ini’, ‘system’) UNSET (‘/host/<Host Name>/xsengine’,’33007′) WITH RECONFIGURE

Remove Volume ID:-

ALTER SYSTEM ALTER CONFIGURATION (‘topology.ini’, ‘system’) UNSET (‘/volumes’, ‘<database_id>:X’) WITH RECONFIGURE

here X is the volume id

Once the above commands executed successfully, then check if the xs service with error is removed or not.

Conclusion

• Unwanted XS engine service is removed.
• One engine with port 33040 is up and running.
• There is no error in the overall status of the HANA database.
•  Now we are able to take complete DB backup of the tenant database.