FAQ about SAP HANA backup - Cloud Backup

This topic provides answers to some frequently asked questions (FAQ) about the SAP HANA backup feature of Cloud Backup.

What is SAP HANA backup?

SAP HANA backup is a backup feature provided by Cloud Backup that allows you to manage your SAP system on Alibaba Cloud.

SAP has certified Cloud Backup for integration with SAP HANA Backint. Cloud Backup is compatible with SAP HANA 1.0 and 2.0. You can use a Cloud Backup client to back up SAP HANA databases deployed on Elastic Compute Service (ECS) instances and restore the databases based on your business requirements. For more information, see Overview of the SAP HANA backup feature.

You can also back up on-premises files and VMWare virtual machines (VMs) in data centers to backup vaults on Alibaba Cloud. Cloud Backup provides simple and easy-to-use native data protection features for various types of data on Alibaba Cloud, such as ECS files, Oracle databases, SQL Server databases, File Storage NAS (NAS) file systems, and Object Storage Service (OSS) objects. For more information, see What is Cloud Backup?

Application scope of SAP HANA backup

SAP HANA databases deployed on ECS instances.
Backint supports multitenant database containers (MDCs) in SAP HANA 1.0 SPS 09 (revision 94) and later and SAP HANA 2.0 SPS 01 and later. Backint does not support single-container systems in SAP HANA 1.0.

How do I view the status and logs of the Cloud Backup client after I register an SAP HANA database?

After you register an SAP HANA database in the Cloud Backup console, the SAP HANA database is in the Registered state.

The default log path is /opt/alibabacloud/hbrclient/logs.

You can run the ps axu|grep hybrid command to view the status of the Cloud Backup client. If the process information exists, the Cloud Backup client is started and running properly.

root     11472  0.0  0.0   9288  1552 pts/2    S+   16:11   0:00 grep --color=auto hybrid
root     30480  0.0  0.2  56296 17028 ?        Ssl  13:26   0:04 /opt/alibabacloud/hbr/client/hybridbackup -p 0

Backup log paths

Logs of a Cloud Backup client for SAP HANA backup: /opt/alibabacloud/hbr/logs

Backint logs of SAP HANA databases: /usr/sap/{SID}/SYS/global/hdb/logs/

Backup logs of SAP HANA databases: /usr/sap/{SID}/HDB{InstanceNumber}/{hostname}/trace/DB_{DBNAME}/backup.log

SAP HANA databases automatically manage and store logs. You can use HANA Studio or other related tools to execute the following SQL statements to query and obtain the backup content in the logs:

select CAT.* from SYS_DATABASES.M_BACKUP_CATALOG CAT JOIN SYS_DATABASES.M_BACKUP_CATALOG_FILES FILS on CAT.BACKUP_ID = FILS.BACKUP_ID where CAT.entry_type_name = 'log backup' and CAT.state_name = 'successful' and FILS.DESTINATION_TYPE_NAME = 'backint' and CAT.database_name = 'SYSTEMDB' order by sys_end_time

What do I do if a database cannot be connected when I restore the database to the source SAP HANA instance?

When you create a restore job and restore a database to the source SAP HANA instance, the database cannot be connected. In this case, perform the following steps:

Check whether the SAP HANA database is started.
Check whether the SSL certificate has expired. If the certificate has expired, perform one of the following operations:
- Replace the certificate.
- Specify that the SSL certificate is not verified in the console.

What do I do if no data is obtained when I restore a database to the source SAP HANA instance?

When you create a restore job and restore a database to the source SAP HANA instance, no data exists on the selected database. In this case, check whether the client status is normal.

What do I do if I cannot find the backup record during restoration?

Issue
The backup record may not be found if you create a restore job after the operating system is reinstalled, the snapshot is rolled back, or the SAP HANA database is uninstalled and reinstalled on the ECS instance.
Cause
When you restore the database to the source SAP HANA instance, Cloud Backup first retrieves the backup records in the preconfigured SAP HANA backup path. Note that if the operating system is reinstalled, the snapshot is rolled back, or the SAP HANA database is uninstalled and reinstalled on the ECS instance, the backup records stored in the HANA database may be cleared.
Solution
- If you have enabled Use Backint for Catalog Backup during the backup, you can restore the database. Perform the following steps:
  1. Log on to the source SAP HANA instance and delete the ECS instance.
  2. Register a new SAP HANA instance and use the same parameter configurations as the previously registered SAP HANA instance. Install a Cloud Backup client and add the deleted ECS instance.
  3. Create a restore job and select the newly registered SAP HANA instance as the source instance for restoration. In other words, restore the database from the source SAP HANA database to another SAP HANA instance.
- After the database is restored and if the backup data of the source SAP HANA instance is no longer used, you can delete the source SAP HANA instance. If you have not enabled Use Backint for Catalog Backup during the backup, the backup records cannot be found, but the backup data still exists. For more information about how to restore the backup data, see Restore a database to an SAP HANA instance by specifying a prefix.

What do I do if SQL statements fail to be executed on an SAP HANA database?

The HANA log space is used up, which may cause the failure to execute SQL statements. Clear the disk space and try again later.

How do I manually delete backup records?

You cannot manually delete SAP HANA data from Cloud Backup. You can only wait until the data automatically expires. You can select the following option to delete data by using SAP Studio.

What do I do if the instance is activated but an internal error message appears on the database page?

If an error message appears on the SAP HANA Backup page of the Cloud Backup console, check the HANA license. You can connect to SYSTEMDB and execute the following SQL statement to query whether all databases contain licenses. If no result is returned, a license is missing for a database.

SELECT * FROM M_LICENSE

For more information, see https://launchpad.support.sap.com/#/notes/2619291.

FAQ about backup failures

If the following error message appears in the /opt/alibabacloud/hbr/logs/hybridbackup.log file, the local time is significantly different from the server time. We recommend that you adjust the local time first, or enable automatic Network Time Protocol (NTP) synchronization to ensure time consistency.
```
time="2021-11-04T16:24:17+08:00" level=info msg="InvalidTimeStamp.Expired retry, retryDelay: 5000 ms, retry times: 14" file=client.go line=377
```
If a backup job fails or all backup jobs are canceled (not manually canceled) and "No space left on device" appears in the backup.log file, the local disk space is used up and needs to be cleared.

If the following error message appears in the /opt/alibabacloud/hbr/logs/hybridbackup.log file and no error message appears in the console, you may have configured another scheduled backup job, which conflicts with the SAP HANA backup job during execution.

time="2021-08-29T01:10:00+08:00" level=error msg="Execute hana backup failed : hbr: client returned error: ErrorCode=HanaSqlError, ErrorMessage=SQL Error 447 - backup could not be completed: [110122] A data backup cannot be created because another data backup is running or a storage snapshot has been prepared., Data=, values=map[]" file=hanabackupjob.go line=98

If an unexpected backup failure or non-execution alert occurs, and no record of backup completion exists in the backup history, the MQTT request may time out. You can view the logs at the corresponding point in time in the /opt/alibabacloud/hbr/logs/hybridbackup.log file.

If the following error message appears in the /opt/alibabacloud/hbr/logs/hybridbackup.log file, the password may have expired and need to be updated in a timely manner.

time="2023-11-26T00:00:08+08:00" level=error msg="SAP Error: SQL Error 447 - backup could not be completed: [110203] Not all data could be written: Expected 4096 but transferred 0, [110507] Backint exited with exit code 1 instead of 0. console output: Internal Error: The user account is in unknown status. " file=errorwrapper.go line=28

If the following error message appears in the /opt/alibabacloud/hbr/logs/hybridbackup.log file, the server may reject the request because your timestamp is inaccurate.
```
time="2024-06-23T01:36:46+08:00" level=error msg="HBR DescribeUserBusinessStatus returns hbr: service returned error: StatusCode=400, Code=InvalidSecurityToken.Expired, Message=Specified SecurityToken is expired., RequestId=A6CDF56F-CA56-53E8-9342-24E19F768D40" file=client.go line=428
```
Use one of the following methods to check the timestamp:
- Run the following command and check the System Time parameter in the command output. This parameter reflects the difference between the system time and the NTP time. If the time difference is within a few milliseconds, the timestamp is in the normal state.
```
sudo chronyc tracking
```
- Run the following command and check the offset parameter in the command output. This parameter reflects the difference between the system time and the NTP time. If the time difference is within a few milliseconds, the timestamp is in the normal state.
```
ntpd -q
```
Assume that no failure record exists in the console and the following error message appears in the /opt/alibabacloud/hbr/logs/hybridbackup.log log:
```
SQL Error 447 - backup could not be completed: [110122] A data backup cannot be created because another data backup is running or a storage snapshot has been prepared.
```
Use one of the following methods:
1. Check whether other backup software performs HANA backup at the same time.
2. Restart the HANA instance when backup data exists. For more information, see SAP Knowledge Base.

What do I do if an error occurs when I view a backup job?

Issue: The following error message appears when you view a backup job.

In addition, the following error message appears in the /opt/alibabacloud/hbr/logs/hybridbackup.log file:

time="2023-12-01T14:38:23+08:00" level=error msg="prepare stmt SELECT count(*) FROM sys_databases.M_BACKUP_PROGRESS error : SQL Error 437 - only commands for license handling are allowed in current state" file=db.go line=220

Solution: SAP HANA 2.0 requires license registration, and therefore the multi-user mode is required.

What do I do if a restore job fails?

Failure: The restoration fails if you select an earlier backup point when you restore data by using the Specify Time or Specified Backup method, and then select the latest backup point to restore data again by using the Specify Time method.

Solution: If you want to restore data for a consecutive number of times, we recommend that you use the Specified Backup method and select a backup point to restore data.

Does Cloud Backup support backup of the SAP HANA databases deployed in a self-managed data center?

No, Cloud Backup does not support backup of the SAP HANA databases deployed in a self-managed data center. However, you can back up the SAP HANA databases to an on-premises storage, and then back up the databases to the cloud by using the on-premises file backup feature. For more information, see Back up on-premises files.

Do I need to purchase another Alibaba Cloud storage service to back up SAP HANA databases?

No, you do not need to purchase another Alibaba Cloud storage service. Cloud Backup uses Backint to directly call the API for SAP HANA backup. Data is backed up to the cloud storage at the Cloud Backup backend through pipes. This does not occupy the storage space of the ECS instances where the SAP HANA databases are deployed. Therefore, you do not need to purchase another Alibaba Cloud storage service.

Can I use Cloud Backup to back up SAP HANA databases that are deployed in single-container systems?

No, the SAP HANA backup feature in the Cloud Backup console uses the Backint API. To back up an SAP HANA database that is deployed in a single-container system, you can adopt either of the following solutions:

Solution 1: Back up the SAP HANA database to the disk of an ECS instance, and then use the on-premises file backup feature of Cloud Backup to back up the database. For more information, see Back up on-premises files.
Solution 2: Convert the SAP HANA single-container system to an SAP HANA MDC system. For more information, see SAP official documentation or consult your SAP partner.

Can I store the backup data of SAP HANA databases for different environments in separate backup vaults?

Yes, you can store the backup data of SAP HANA databases for different environments in separate backup vaults. When you register an SAP HANA database in the Cloud Backup console, you can create a backup vault or select an existing backup vault. The following restoration methods are supported:

Does SAP HANA backup support the cross-region (remote) backup feature?

Yes, SAP HANA backup supports the cross-region (remote) backup feature. For more information, see Back up data across regions.

What are the precautions for configuring the SAP HANA backup feature?

If your SAP HANA database is deployed in a high-availability architecture, you must specify a high-availability virtual IP address (HAVIP) for the ECS instance where the SAP HANA database is registered. This ensures that backup jobs can run properly when a failover is triggered in the cluster.
By default, the Use Backint for Catalog Backup and Auto Log Backup settings are not enabled in the backup parameters. You must manually enable the settings for the SAP HANA system database and each tenant database to ensure that the databases can be restored when required.

Note

Tenant databases inherit the parameter settings of the system database. Check that the parameter settings of each database meet your business requirements.

How do I configure the retention period of backup data for an SAP HANA database?

Log on to the Cloud Backup console and select the SAP HANA instance.
On the Databases tab, select a system database or tenant database, and then choose More > Configure Retention Policy in the Actions column.

The default backup retention period is Permanent. Change the value based on your business requirements.

Parameter	Description
Retention Policy	Custom Select this option if you need to specify a limited retention period. You must also specify an interval at which retention jobs are run. Permanent If you select this option, Cloud Backup permanently retains your backup data.
Retention Job Interval	This parameter is required only if you set the Retention Policy parameter to Custom. The interval at which retention jobs are run. The time is accurate to seconds. Note We recommend that you back up your data during off-peak hours.
Retention Period	This parameter is required only if you set the Retention Policy parameter to Custom. The retention period of backup data. Unit: days, weeks, months, or years. The minimum retention period is one day, and the maximum retention period is 10 years. Note Cloud Backup deletes the expired catalogs and data that are related to Backint and file backup. The deleted catalogs and data cannot be restored. We recommend that you set the retention period based on your business requirements.

What do I do if a Cloud Backup client cannot be installed for SAP HANA backup because multiple /usr/sap/<SID>/SYS/global/hdb/opt directories exist?

Connect to the ECS instance.
Change the names of the /usr/sap/<SID>/SYS/global/hdb/opt directories for the SAP HANA databases that do not require backup to /usr/sap/<SID>/SYS/global/hdb/opt_backup.
Log on to the Cloud Backup console, and then reinstall the Cloud Backup client for the SAP HANA database.