Applications of any type that read and write data to and from storage can suffer from loss of storage, access, or data. Many organizations consider data high availability (HA) and redundancy as mandatory requirements rather than optional ones. Applications accessing data are always expecting the data, and the storage that the data resides on, to be available at all times. If for some reason the storage is not available, then the application ceases to function.

Storage availability is the requirement to protect against loss of access to stored data or loss of the storage in which the data resides. Storage availability is subtly different from data loss. In the case of data loss, whether due to accidental deletion, corruption, theft, or another event, you can recover the data from a snapshot, backup, or some other form of archive. If you can recover the lost data, it means that you previously had a process to copy data, either through snapshot, backup, replication, or another data management operation.

In general, the net effect of data loss or lack of storage availability is the same—loss of productivity. But the two types of data loss are distinct and addressed in different ways.

The subject of data availability in conjunction with the product family is documented in a number of white papers and other documents that describe the use of snapshot technology and data replication as well as backup and recovery tools. To read the white papers, go to Riverbed Community at https://community.riverbed.com.

Core HA and Edge HA are independent from each other. You can have Core HA with no Edge HA, and vice versa.