Traditional backup systems typically are set to run at specific intervals, usually after hours. At this time you create a copy of your data at an exact moment in time to your specified location But what if you need Data captured from a specific time of the day and it was overwritten? This is a major flaw of the commonly used backup process by many organisations. Continuous data protection is a new backup approach that uses a different method of operation. Rather than backing up your data during intervals, it will back up your data whenever you make a change to it. In his article, we will discuss what is Continuous Data Protection and its advantages and disadvantages.
What is Continuous Data Protection?
Continuous data protection (CDP) is an approach to recovery that continuously, or nearly continuously, captures and transmits changes to files or blocks of data while journaling these changes. Often, this will be directed to a disk at the same site as the source so that it provides a method of effecting a very quick recovery of data. This capability provides the option to recover many more-granular points in time to minimize data loss and enables arbitrary recovery points.
As many enterprises have infrastructure that is hypervisor-based, continuous data protection software can also record changes to data in virtual machines. Additionally, some CDP vendors make it simple to save changes to two separate locations; for instance, one copy onsite for quick recovery and a second copy located elsewhere for robust disaster recovery needs.
Difference Between True CDP and Near-CDP
True CDP is the process where data copies are captured every time there is a data change at the source and is a continuous incremental recording process. True CDP offers a recovery point objective (RPO) of close to zero, which means there is no data loss.
Near-CDP, as the name indicates, is a near-continuous process where there is a pre-defined time interval for snapshotting the data. Near-CDP offers an RPO of however-often-you-are-taking-a-snapshot (typically one hour).
Benefits of Continuous Data Protection
The primary benefit of using the Continuous Data Protection method is that it offers a near-zero recovery point objective (RPO) which is the period of time in which an enterprise’s operations must be restored following a disruptive event. When compared to traditional backup systems, continuous data protection offers a higher level of protection against data loss. As previously mentioned, most traditional backup systems will only create data backups during specific intervals. If you experience a data loss event before this interval — and you create new data shortly thereafter — you may lose some of the newly created data.
Another benefit of CDP is that it eliminates the challenges that most organisations face when performing their backups within the allocated backup window. With the growth of data, organisations are struggling to complete their scheduled backups within the specified window of time set aside.
Continuous data protection isn’t for everyone but it is a great fit for most organisations. It does bring with it a number of challenges to consider. First of all, it requires physical disk storage that offers fast performance and therefore can raise costs. As the data is stored on a server, that server could be a single point of failure. It’s critical to ensure high data availability to counteract that risk. Finally, CDP puts increased pressure on your data resources. Because every change to data is saved to backup in real-time, your data throughput is essentially doubled—which could potentially affect system stability or performance.
