EMC storage virtualization upgrades bring VMware interoperability

EMC today unveiled the first major upgrade to its storage virtualization (compare products) technology since releasing the product in mid-2005, adding full interoperability with VMware and new features designed to improve availability and scalability.

EMC’s Invista is a block storage virtualization product that combines hardware and software to move data among physical storage without affecting production applications. With today’s release of Version 2.0, EMC says Invista has been tested, optimized and certified for use with VMware’s popular ESX server virtualization product.

That may be no surprise given that EMC owns VMware, but the certification is actually a “very big deal” for customers, says analyst Arun Taneja of the Taneja Group. 

“Customers find that when they implement server virtualization but use the same storage, all of a sudden that storage becomes a huge bottleneck,” Taneja says. “Storage has to be reconceptualized … in the world of server virtualization.”
EMC attempts to differentiate itself from competitors IBM and Hitachi Data Systems by using a so-called “split path architecture.”

IBM’s SVC storage virtualization product and Hitachi both use an “in band” system, in which the storage virtualization hardware sits between the server and storage, so data must travel through the storage virtualization device. EMC claims this creates a data integrity risk and slows performance.

Invista’s split path architecture separates the data path and control path, so the control information goes through the Invista device but data moves directly and quickly from storage to the server, Taneja explains.

Each approach has its pros and cons, he says. EMC’s product is scalable to larger implementations than in-band devices, but the in-band devices are simpler and can operate with less expensive switches, he says.

Invista starts at $100,000, a price that gives customers the ability to virtualize up to 14 terabytes of data, says Rob Emsley, senior director of product marketing at EMC’s software group. Invista is configured to work with Cisco and Brocade switches though the switches themselves are an extra cost, he says.

Upgrades to Invista include an increase in the number of data movements that can happen concurrently from eight to 40, Emsley says.

A second upgrade that improves availability allows customers to separate the control path cluster – the part of Invista that creates virtual volumes. Previously, Invista control elements had to run in the same rack, but now they can be separated by up to 300 meters, according to Emsley. This way, if a power outage or fire affects one part of a data center, the problem would be restricted to virtual storage in just that one part, he says.

Another upgrade introduces data pooling and mirroring functionality that makes it easier to use tiered storage, EMC says.

“Customers can now create storage pools, which they can define in tiers,” EMC states in a press release. “Customers can then map their most critical applications to their best-performing tier-1 storage, while tier-2 storage can be tasked with supporting development and noncritical applications. Mirrored copies can also now be placed across different tiers. Both of these functions enable greater utilization across all virtualized storage assets.”