When linking a dSource from a SQL Server source database, Delphix offers five (5) different methods of capturing backup information:

• Delphix Managed Backups, where the Delphix Engine schedules and initiates the backups from the source database, and captures them
• SQL Server Managed Backups, where the SQL Server source database schedules and initiates backups and the Delphix Engine captures them
  • Full backups
  • Full or differential backups
  • Transaction log backups (with LogSync disabled)
  • Transaction log backups (with LogSync enabled)

Delphix Managed Backups are conceptually a lot simpler to explain, but they can be considered less desirable because they might be viewed as intrusive. SQL Server Managed Backups are explained in two sections:  

• the initial load of the dSource from the the source database 
• subsequently keeping the dSource synchronized with the source database.

Below is a brief explanation of how these two different modes of operation work, illustrated with the relevant screen shots of the Data Management page of the Add dSource wizard.

Delphix Managed Backup Mode

When the checkbox for Delphix Managed Backups is selected, the Delphix Engine will initiate a COPY_ONLY full backup of the source database for the initial load of the dSource. Thereafter, the Delphix Engine will initiate COPY_ONLY full backups of the source database using the schedule specified by the selected SnapSync Policy. If you select the None policy, the Delphix Engine will not automatically initiate COPY_ONLY backups, but you can initiate them manually using the snapshot (camera) icon.

You must specify the SQL Server instance on a standalone Windows server (called the Staging Environment) to which the backups will be restored. It is also necessary to select the SnapSync Policy.

SQL Server Managed Backup Modes

Initial Load of the dSource

When the checkbox for Delphix Managed Backups is left unchecked (default), the Delphix Engine will rely on the source database to create backups that the Delphix Engine will use to keep the dSource in sync with the source database.

For the initial load of the dSource, you can choose one of the following:

• have the Delphix Engine initiate a COPY_ONLY full backup
• use the most-recent existing full or differential backup (default)
• use a specific existing full or differential backup identified by its backup_set_uuid

The Delphix Engine supports source database backups that SQL Server creates natively, as well as backups created by Quest/Netvault LiteSpeed and Red Gate SQL Backup Pro. For more information, see the topic Supported OS, SQL Server, and Backup Software Versions for SQL Server.

Once you have decided how the dSource will be initially loaded, specify the SQL Server instance on a stand-alone Windows server (called the Staging environment) to which these backups will be restored.

The Backup Path tells the Delphix Engine where to look for backups of the source database.

• If Autodiscover is selected, the exact path used to take the backup from the source database will be determined by querying by the source database instance. If this option is used, the Source database should take backups to a UNC path (Windows file share) so that they are accessible to the Staging server.
• If a custom path is specified, the Delphix Engine will query the source database instance, identify the filename of the source backup, and then recursively search the specified Backup Path for this filename. This should also be a UNC path (Windows file share) which is accessible to the Staging server.

The path used to restore backups must be readable by the Windows server hosting the staging instance, using the staging environment's configured Environment User.  For more information, see Windows Users and Permissions on Database Servers.

Keeping the dSource Synchronized with the Source Database

Next, specify how the Delphix Engine will capture subsequent backups of the source database.

The selected Validated Sync mode determines how often the Delphix Engine will check for new backups, and which type of backups it will check for. You can always force synchronization with the source database by clicking the camera icon for the dSource on its Configuration tab.

Summary of Validated Sync Modes

This table summarizes each mode of Validated Sync, displaying how often the Delphix Engine will poll to check for new backup files, when it creates snapshots for the dSource, and whether point-in-time restores for provisioning and refreshing virtual databases (VDBs) is possible or not.