Key Concepts in DPM Data Protection
Published : April 8, 2005 | Updated : August 17, 2005
To understand the processes involved in protecting and recovering data in DPM, you need to be familiar with a few key concepts. Table 1 1 gives a brief explanation of the concepts that are most basic to data protection and recovery processes in DPM. For a full listing of DPM terms and concepts, see the “Glossary” section of this guide.
Table 1 1 Key Concepts in DPM Data Protection
Concept |
Definition |
|---|---|
storage pool |
The storage pool is a set of disks on which the DPM server stores replicas, shadow copies, and transfer logs for protected data sources. |
protection group |
A protection group is a collection of data sources, such as volumes or shares, that have a common protection configuration and schedule. Data sources within a protection group are referred to as “protection group members” or simply “members.” |
replica |
When a protection group is created, a replica is created for each volume that is included in the group. A replica is a complete copy of the protected data on a single volume. Stored in the storage pool on the DPM server, each replica contains all the properties of the volume, including security settings and sharing. |
shadow copy |
A shadow copy, also referred to as a “snapshot,” is a point-in-time copy of a replica stored on the DPM server. DPM creates shadow copies of each replica in a protection group according to a specified schedule. Users can access the shadow copies to recover previous versions of files in the event of data loss or corruption. |
replica creation |
Replica creation is the process of creating the initial replica of protected data in the storage pool on the DPM server. You can either prompt DPM to copy the data from the file server over the network, or you can manually create a replica from a tape backup or other removable storage medium. |
synchronization |
Synchronization is the process by which DPM transfers data changes from a protected file server to a DPM server, and then applies the changes to the replica of the protected data. DPM relies on synchronization to keep replicas consistent with the protected data on the file servers. |
synchronization with consistency check |
Synchronization with consistency check, also referred to as a “consistency check," is the process by which DPM checks for and corrects inconsistencies between a protected volume and its replica. As part of the synchronization process, a consistency check performs block-by-block verification to ensure that all the data on the replica is consistent with the protected data. |