In this post, we will try to understand what are all HANA backup types and significance of those backups. Also how to manually take backup via SAP HANA Studio.
What is Data Backup?
- A data backup includes all the data that is required to recover the database to a consistent state.
- With a data backup, only the actual data is backed up; unused space in the database is not backed up.
- The data area is backed up in parallel for each of the SAP HANA services. If SAP HANA is running on multiple hosts,
- While a data backup is running, some data integrity checks are performed. If these checks are successful, the data is written to the backup destination.
- Each time you start a file-based data backup, you have the option to change the default backup destination or to specify a different destination from the default only for the current backup.
- By default, file-based data backups are written to $DIR_INSTANCE/backup/data.
What is Delta Backup?
- Delta backups allow you to reduce the amount of data that is backed up, compared to full data backups. In turn, this means that delta backups are normally faster to create than full data backups.
- Delta backups are supported with SAP HANA SPS10 or newer.
What is Differential Backup?
- Differential Backup consists of the data changed since the last full data backup.
- Backup size of the differential backup is the amount of data to be saved with each differential backup increases.
- If your backup strategy is based on only full data backups and differential backups, only two backups are needed for a recovery: a full data backup and one differential backup.
What is Incremental Backup?
- Incremental Backup consists of the data changed since the last full data backup or the last delta backup (incremental or differential).
- If your backup strategy is based on only full data backups and incremental backups, to recover the database, SAP HANA needs the following backups:
- The full data backup on which the incremental backups are based
- Each incremental backup made since the full data backup
- In some situations, a large number of incremental backups may be needed for a recovery.
You could recover SAP HANA to a specific point in time using the following sequence of backups:
- Full data backup
- Differential backup
- Incremental backup 1
- Incremental backup 2
- Log backups
Now we will try to take the complete backup of our production system via HANA Studio.
Select the system and dropdown to open all available options. Right click “Backup” and click “Back Up System”
We can also double-click the “Backup” button and click below highlighted button to take system backup.
Now we will be prompted to choose “Backup Type” and “Destination Type”
Select a backup type.
|Complete Data Backup||A data backup includes all the data structures that are required to recover the database.|
|Differential Data Backup||Differential backups store all the data changed since the last full data backup.|
|Incremental Data Backup||An incremental backup stores the data changed since the last full data backup or the last delta backup (incremental or differential).|
Select a destination type:
|File||Writes the backup data to the file system.
Each SAP HANA service writes backup data to a separate file in the specified destination in the file system.
|Backint||Writes the backup data through a third-party backup tool.
Each SAP HANA service starts the Backint for SAP HANA agent and sends the backup data to the third-party backup tool.
Note: This option is only available if a third-party backup tool is installed.
In below screen, it will provide a summary of system definition and Backup definition.
Now backup has started and all 3 servers (XSEngine, Name Server and Index Server) backup takes place in parallel.
Once backup will be completed, we will receive the backup completed screen.
Inside Backup Catalog we can see the history of backups.
So here we see backup which completed right now.
When we will check at OS level Backup path, we will have 4 databackup files
|0 topology||Nameserver <hostname> 0.00GB /hana/backup/<SID>/data/2017-12-07_00-00_databackup_0_1|
|1 volume||nameserver <hostname> 0.20GB /hana/backup/<SID>/data/2017-12-07_00-00_databackup_1_1|
|2 volume||xsengine <hostname> 0.14GB /hana/backup/<SID>/data/2017-12-07_00-00_databackup_2_1|
|3 volume||indexserver <hostname> 16.39GB /hana/backup/<SID>/data/2017-12-07_00-00_databackup_3_1|
Please note:For production system, we should schedule daily automatic backup (preferably at non-business hours).
System don’t need to be shutdown to perform complete system backup.