Storage

In an orthodox method, the storage used to be consolidated on a central attached storage however, our new concept of hosted models, as well as cloud, allow the central NAS storage to be a Filer from either EMC2 or NetApp. SAP database can be stored on either NAS or SAN from NetApp as well as EMC2. No doubt, both our storage providers have delivered a very high level of understanding of technology to provide the pay-per-use models. The storage has the ability to share the file system and mount one partition on different servers with read-only attributes thus creating a cluster environment without the need of any additional cluster services. The technology of storages has developed a network Appliance product class named Filer & Celerra which is very essential in the entire hosted solution. With the help of these classes, provision of nested export function is enabled which is a very important function for Hosted SAP realization. The storage is designed in such a way that it reduces the amount of “lost” disk space because multiple SAP instances share the same set of disks. It is also easy to extend the disk space by adding more disks to the storage without occurrence of any downtime.

Snapshots

When a snapshot is taken, just the information where the data blocks are located is saved and no data blocks are copied. If data blocks are modified, it is written to a different location, while the original data block is preserved along with content. Since a very small amount of data needs to be copied, the time to create a snapshot is very small. The performance of storage system and throughput is not affected by creation of snapshot.

The Celerra feature creates a read-only, logical image (checkpoint) of a production file system (PFS) that reflects the state of the PFS at the point in time that the checkpoint is created. SnapSure can maintain up to 96 checkpoints of the PFS while allowing PFS applications continued access to the real-time data.

Checkpoints can serve as a direct source of data for applications that require point-in-time data but do not demand real-time data. Such applications include simulation testing, data warehouse population, and automated backup engines that perform backup to tape. You can also use a checkpoint to restore a PFS or part of a file system (for example, a file or directory) to the state in which it existed when the checkpoint was created.