The SQL Anywhere VSS writer service can be enabled to allow for VSS snapshots of the OASIS database if it is hosted in a virtual environment. Per SAP, this is a fully supported solution and should theoretically work fine for OASIS. The users may experience slower performance or freezes in OASIS while a snapshot is being taken.
Enabling the SQL Anywhere VSS Writer Service
Navigate to the OASIS installation directory, then to the asa16\Bin64 subfolder (the full path is typically "C:\Program Files\OASIS273\asa16\bin64"). Open an administrative command prompt and run the following command:
dbsvc.exe -as -s Automatic -t vss -w SAVSSWriter-OASIS "C:\Program Files\OASIS273\asa16\Bin64\dbvss16.exe"
You should see a result similar to the following:
SQL Anywhere Service Utility Version 18.104.22.1685
Service "SAVSSWriter-OASIS" was created successfully.
This service must now be enabled either through ASA Configuration or Windows Services. Once this is done, the database should automatically react to VSS freeze and thaw commands. The new service will automatically start and stop with Windows and can be started and stopped at will if needed using ASA Configuration or Windows Services.
Restoring a VSS snapshot
In the event of database corruption or other failure requiring a restoration from a snapshot, the database from the restored snapshot should be validated to ensure data integrity before allowing users to connect to it. Failure to do so could result in lost work and user frustration. Depending on the size of the database and amount of RAM available, the validation could take several hours to complete. In a recovery scenario, "better safe than sorry" is the rule.
Here is a help document on how to validate the database: Validating the Database
Here is a video walk-through of the validation process: http://www.oasissalessoftware.com/OASIS/VKB/V0000003R01/V0000003R01.htm
If you enable this functionality in your environment, create snapshots of your OASIS virtual machine, and test a disaster recovery scenario where the VM snapshot is deployed and the database validates successfully, please let us know. Lack of support for this functionality is due to a lack of a test environment and real world examples. Any additional information helps.