Copy data management (CDM) is a relatively new term for many in Information Technology. At first literal consideration, its meaning seems self-evident. However, it is really a topical area that vendors address with new products and terminology.
Making copies of data for IT applications is a fundamental task. The how and why have been evolutionary processes. New developments have come from vendors to deliver solutions to manage and automate CDM.
The “why” of making copies starts with the basic function of data protection. Protection is from a disaster (which also includes an orchestrated recovery process) or from corruption or deletion due to application, user, or hardware error. The copy can also be used to create a point-in-time record of information for business or governance reasons.
Another reason for making a copy is to use that data for more than just the primary application. This could be for test/development, analytics, or just because the application owner or administrator just feels safer having another copy. Especially in the case of test/development and analytics, another copy insulates the primary application from problems. Besides corruption and deletion, these problems can include potential performance impacts to the primary application.
Making data copies comes at a cost. The different types of copy mechanisms (the “how” of making copies) include making full copies of data or making snapshot copies where only changed data is represented along with the snapshot tables/indexes. The copies can be local, remote or both. Full copies will take time to create and require additional storage capacity. Snapshot copies can grow in capacity over time. All copies not only eventually consume storage space for usage but also consume time and space in backup processes. Copies of data must also be managed, especially snapshots which tend to proliferate.
This sets the stage for copy data management with the goal to orchestrate and automate the management of copies of data and to minimize the impacts on capacity utilization and copy actions. There have been two approaches to address CDM: software to manage copies/processes and a combination of software and hardware to create a “golden” copy to leverage for other needs. The details and merits of each require a more involved evaluation. Managing copies has the potential to improve IT operational processes (including disaster recovery) and minimize costs.
There are a number of considerations, however. CDM crosses responsibility areas from an IT perspective.
- The first area to consider is the backup administrator. The administrator often uses deduplication software or hardware to reduce the size of copies, and no longer sees the proliferation of copies as the problem it once was. Why there are multiple copies being created does not concern backup administrators, and they do not need to be the champion of making changes.
- A storage administrator will manage the storage system and that usually includes managing the snapshot, copy and replication functions. A storage administrator is concerned with the amount of space consumed and will utilize snapshots as a means to reduce space requirements without challenging the application owner/administrator on the need for copies.
- Application owner/administrators sometimes make complete copies of data (databases for example) rather than snapshots to fit their usage. Usually, they will not inform the storage administrator about usage as long as there is enough capacity available. Integration with applications for automation enhances the value of CDM.
Snapshot management with tools outside of storage system element managers is a relatively new task for storage administrators. A useful tool is critically important for effective adoption and to gain confidence for the administrator. The tool manages the lifecycle of a snapshot copy, but the administrator would not think of it in that way.
Consolidating administration of copies – complete or snapshots, local or remote, including cloud – to a single tool has potentially high value. The more difficult part is making changes in the operational and personnel responsibilities. Those who gain from consolidation of these functions may also influence budgeting for the solution.
CDM represents a new tool and embracing a new tool is sometimes difficult. It does not help that there have been inconsistent descriptions from vendors in their effort to market their solution as unique.
Looking forward, CDM could become part of the element manager for storage systems as an integrated function that works for that specific system. This method is probably too limiting in achieving overall value. The process needs to be applied across IT, inclusive of copies at remote or cloud locations. The best way is likely to integrate CDM with overall orchestration software .This will take a long time given the change required for IT. Meanwhile, we will continue to see individual products that provide value for copy data management.
(Randy Kerns is Senior Strategist at Evaluator Group, an IT analyst firm).