Not all CDP products try to capture data at the host level. Revivio Inc.'s CPS-1000 appliance only captures the write I/Os rather than recording all the read and write activity between the back-end storage and the primary data path. Revivio presents LUNs to FC-attached hosts without the need to deploy host-based agents. Administrators may then use their hosts' existing volume management software to set up mirrored volumes that enable writes to their primary storage and write copies to LUNs presented by the Revivio CPS-1000. While this approach is appealing, you need to verify that Revivio's real-time operating system is certified with your storage array and that your array vendors certify interoperability with Revivio's operating system.
The CPS-1000 also needs to respond as fast as the fastest array that a server is configured to access. If it's slower, it's necessary to verify that the latency doesn't impact the performance of the application itself. And the CPS-1000 appliance will only work with servers that have Fibre Channel connectivity.
If you're not using a CDP product, you should consider it. Being able to recover mission-critical data at any point in time is a powerful tool. Most CDP products will fit into existing storage environments at reasonable price points, bringing relief from shrinking backup windows and eliminating the decision of what data you are most willing to lose.
This was first published in October 2004