Commvault BETs versus FETs

Posted 25 February 2016 12:00 AM by Greg Bennett

In our last blog about the Commvault A-Series family of integrated backup appliances, we talked about our two new ‘ROBO’ appliances that are specifically designed for remote sites with smaller capacity requirements and fewer IT resources. As a reminder, the Commvault A210 supports a usable capacity of 12TB and the Commvault A410 supports a usable capacity of 24TB. Both of these complement the Commvault A600 with NetApp E-Series storage that scales from 18TB up to 288TB of usable capacity per appliance. In this blog we’ll address licensing options and try to decode some of the alphabet soup.

All of our appliances can be purchased with either integrated backend terabyte (BET) licensing, which is aligned to the usable storage capacity of the appliance, or purchased as a ‘hardware-only’ option than is sold with our traditional front-end terabyte (FET) capacity-based licensing. What does this mean?

‘Aligned to the usable storage capacity’ means that if you purchase an appliance with 24TB of usable disk capacity (i.e. AFTER deduplication), it includes 24TB of BET licensing with the appliance. So, the licensing is matched with, or aligned to, the usable capacity. Make sense? BET licensing includes support for the most commonly used applications, such as file systems, NAS, virtual machines and databases. Think of it as an all-you-can-eat buffet, as long as the food fits on your plate. Customers who purchase smaller capacities and have lower retention periods tend to favor this licensing option.

FET-based capacity is usually based on the amount of application data read from the source application. For example, if you have a 1TB database to protect, you pay for 1TB of data regardless of the number of backup copies you plan to keep on the backend. FETs represent the total aggregate amount of data BEFORE deduplication and are measured as the current largest aggregate full (or synthetic full) backup performed. This is how Commvault has traditionally sold capacity-based licensing.

As capacity needs increase, the number of copies of data that you want to retain increases (think more than 2 copies), and/or customers want to retain data for longer periods of time (think more than 45 days), customers tend to prefer the hardware only option and use it with a combination of our traditional data protection bundles (i.e. Data Protection Advanced) and one of our more targeted solution sets (i.e. VM Backup and Recovery).

So what does all of this mean for the new ROBO appliances? As a general rule of thumb, the Commvault A210 with 12TB of usable capacity is good for protecting up to 9TB of FET (or application data), assuming standard retention rates of 30 to 45 days. The Commvault A410 with 24TB of usable capacity is good for protecting up to 18TB of FET (or application data), assuming standard retention rates of 30 to 45 days.

This is where my legal friends remind me to add a disclaimer that ‘mileage may vary’ and ‘every environment is different,’ so please check with your account team to ensure you’re picking the option that best fits your specific needs and optimizes your costs.

Now that we have addressed that, please check out the Commvault Backup Appliances page for more information about the complete portfolio of ‘A-Series’ appliances.