Zerto was founded by the Kedem brothers, CEO Ziv and CTO Oded. They sold Kashya to EMC for $153 million in 2006. That turned into a good deal for EMC, which has had success with the RecoverPoint fabric-based replication product it got from Kashya. Zerto takes a different approach to replication. Instead of fabric or host-based replication for applications, Zerto Virtual Replication is a virtual appliance designed to work with VMware virtual machines.

On Monday, Zerto closed a B series funding round led by U.S. Venture Partners with earlier investors Battery Ventures and Greylock Partners participating. The round brings Zerto’s total funding to $21 million.

Ziv Kedem said the rise of server virtualization and the cloud have changed the face of replication for disaster recovery, prompting a shift in focus from physical devices to the hypervisor. Zerto positions Virtual Replication as a method of protection for VMs and applications for enterprise, or as the basis of DR as a service. It replicates specific VMs regardless of their LUNs, works with any storage array and features one-click recovery and WAN compression.

“The thing that’s changed from 2006 to today is the massive disruption of virtualization and the cloud,” Kedem said. “With a physical environment, storage was the center of the data center. Virtual machines have changed that and with the cloud, users just want to manage their applications. They don’t care where they are.”

Kedem said Zerto has about 20 customers in an extended beta program, including cloud providers offering DR as a service. The Virtual Replication product went GA this month. He said the startup will use the new funding to expand its sales and marketing. Kedem said he expects to grow the company from 30 employees today to about 50 by the end of the year.