How Disk Allocation Works
Updated: November 1, 2013
Applies To: System Center 2012 R2 Data Protection Manager, System Center 2012 SP1 - Data Protection Manager, System Center Data Protection Manager 2010
When you create a new protection group, Data Protection Manager (DPM) allocates disk space for the protection group in the storage pool. Based on retention range, work load type and the size of the protected data, DPM recommends the amount of disk space to allocate in the storage pool and verifies that the protected computer contains sufficient space for the change journal.
|To help you in designing a storage layout for DPM, you can use a Storage Calculator that focuses on outlining the storage capacity requirements based on a set of input factors. For more information, see Storage Calculators for DPM (http://go.microsoft.com/fwlink/?LinkID=180658).|
|With data co-location enabled, DPM will allocate fixed size volumes in the storage pool. For more information, see Co-Locating Data on Disk.|
If you are protecting only a subset of the data on the protected volume, you can calculate the size of the protected data so that DPM can adjust its recommendations for disk allocation. To compute the disk allocation using the size of the data on the protected volume, in the ModifyDisk Allocation dialog box, click Calculate.
If the data on the protected volume outgrows the initial allocations, DPM can try to automatically grow the volume by 25% if the option Automatic grow the volumes in the Review Disk Allocation page of the Create New Protection Group wizard is selected. If the auto-grow operation fails, or if the option Automatic grow the volumes is not selected, DPM generates a “Recovery point volume threshold exceeded” or “Replica disk threshold exceeded” alert and provides guidance for increasing disk allocations appropriately.
During creation of a protection group, DPM calculates default space allocations depending on what type of datasource is being protected. You should accept the recommended disk allocations for the protection group unless you are sure that these allocations do not meet your requirements. If you change the recommended allocations, you might get fewer recovery points than you wanted or DPM might allocate more disk space than is needed.
Generally, the recommended allocations provide sufficient storage for at least a couple of weeks of recovery points. If necessary, you can adjust the disk allocations after monitoring disk usage for data protection.
For more information about disk allocations, see Planning Protection Groups.
You can schedule and view reports in the Reporting task area. To view trends in disk usage for a protection group, review a Disk Utilization Report.
For additional resources, see Information and Support for System Center 2012.
Tip: Use this query to find online documentation in the TechNet Library for System Center 2012. For instructions and examples, see Search the System Center 2012 Documentation Library.