Your deployment plan should specify the number of DPM servers necessary to protect your data and where you plan to locate each DPM server on your network.
Your deployment plan should also specify which instance of Microsoft SQL Server each DPM server will use. DPM requires an instance of SQL Server for the DPM and reporting databases. DPM will install SQL Server during installation on the DPM server, or you can use an existing instance of SQL Server on a remote computer.
A critical component of your DPM server configuration is the storage pool, a set of disks that store replicas and recovery points for protected data. The capacity of the storage pool and any custom volumes that you assign to DPM must be sufficient to provide disk-based protection of the selected data sources.
If your deployment plan requires tape-based protection for any data sources, you will need to attach a tape library or stand-alone tape drive to the DPM server.
If you plan to protect a large Windows SharePoint Services farm, you should install DPM on a volume that has sufficient disk space for the DPM database. The DPM database requires about 1 GB for every million items that exist in the farm. For example, if you protect a farm with 5 million items, you would plan about 5 GB storage in the DPM database to hold the catalog for such a farm. This space requirement is in addition to the storage space that DPM requires for the tape backup catalogs, job logs, and so forth.