6. Instant Volume Replication and Low- Capacity Snapshots for Application Testing

Many organizations develop applications. In most cases, development teams need real data for development and testing purposes. Replicating a volume may take a long time until the entire data set is copied. Sometimes, several teams need the data for independent tests simultaneously, resulting in multiple replications using a substantial amount of storage space.

There are a few software vendors that provide an “instant copy” option, in which copies are ready for use within seconds, and the data is then copied in the background. In addition, there are low-capacity snapshot solutions that enable us to simultaneously assign the same snapshot to multiple servers for independent read and write purposes.

Using instant physical copies in conjunction with the above low-capacity snapshot solution enables the fast creation of a replication and the assignment of snapshots in parallel to multiple servers, each may be used by different testers or developers for independent purposes. Using this solution, developer’s time is saved as well as a significant amount of storage space.

If a test fails, the tester or developer would typically like to run another test on the same data for debugging purposes. With this solution, there is no problem re-assigning a new snapshot with the replicated data.


7. Cost-Effective Disaster Recovery Site

Disaster recovery solutions are usually very expensive. The most trivial solution requires a mirrored site with the same equipment as the original site, connected via fiber channel lines and its data synchronously mirrored to the remote site.

While synchronous mirroring guaranties no data loss, there are cases that mirrored data is not usable due to lack of integrity. Some applications cannot use data unless data integrity is guarantied. In those cases, and many cases when same data may be lost (Recovery Point Objective, RPO >0) asynchronous mirroring may be used. The use of asynchronous mirroring enables the use of much cheaper IP lines. In many cases, these network lines already exist. Snapshot based mirroring enables further reduction of the required bandwidth (and cost) since it transfers only the changed data, regardless of how many times it was changed during the snapshot period.

Storage at the DR site does not need to be same as the original site. The DR site may use cheaper storage, and operate at somewhat lower performance.

8. Use Snapshot-Based Backup

As the amount of data for backup increases, it becomes more costly. In order to minimize disruption to production servers, backups are executed during the night independently and without supervision. This may result in failures, or alternatively, organizations pay extra for a night shift to be present during the process. Due to increasing production requirements and increasing data capacities, backup windows are in many cases not large enough to complete the required task. This leads to huge infrastructure upgrade expenses (e.g., servers, LAN, faster tapes, etc).