(SP23) Point-In-Time Recovery
- SNP
- Martina Pospisilova (Unlicensed)
- Anonymous
The Point-In-Time Recovery (PIT) recovery feature allows to make the state of an archive consistent with a primary database. In case the archive (i.e. Hadoop) has been restored to a certain moment and is now in an inconsistent state, this functionality analyzes the situation and performs the synchronization of the archive.
The PIT recovery feature allows to recover only the changes performed by the OutBoard DataTiering with NLS. These changes are:
- Archiving
- Reloading
- Writer operations
- Change of the structure
Other limitations are mentioned in table below:
| Functionality | Limitations |
|---|---|
| InfoProvider type |
|
| Aging profile |
|
| Target storage type |
|
Point-in-time Recovery Setup
Before you can start using this functionality, you should create a new binary storage where PIT changelog will be stored. Go to transaction /DVD/SM_SETUP and click on New Storage. In a pop-up window fill in these parameters:
- Storage ID
- Storage Type: BLOB
- Blob Size: recommended value is 32 000, maximum size depends on the type of the primary database
- Data Class
- Database Prefix: prefix of the changelog table name
Go to Expert settings, choose DEFAULT InfoProvider and set its parameter PIT_BIN_STORAGE to Storage ID of your binary storage.
If you want to enable PIT recovery for all your InfoProviders, set parameter USE_PIT_HANA to X for DEFAULT InfoProvider. This will enable PIT recovery and create a PIT changelog for all newly created DAPs of the InfoProviders. If there are already some DAPs existing, you have to run report /DVD/NLS_PIT_ENABLE for these InfoProviders (we recommend to run it in the background as it may take a while).
If you want to enable PIT recovery just for some InfoProviders, set parameter USE_PIT_HANA to X for these specific InfoProviders and save it. This will create the PIT changelog right away.
It is possible to recover only changes performed after the PIT changelog creation.
Housekeeping
To delete the PIT changelog data older than a retention period, use report /DVD/SM_HANA_CHL_DELETE. If you leave the select option for InfoProviders empty, it will delete the PIT changelog data for all InfoProviders. The idea is to schedule the execution of this job periodically to avoid growth of the database.