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VMware Introduces Open Virtual Machine Disk Format Specification

VMware Introduces Open Virtual Machine Disk Format Specification

Specification Enables Broad-based Usage for Virtualization Industry

PALO ALTO, Calif., April 3, 2006 — VMware, the global leader in virtual infrastructure software for industry-standard systems, today announced that its virtual machine disk format specification for defining and formatting virtual machine environments is now openly available, downloadable and free of charge. This will enable use by all developers, software vendors and projects and includes open licensing compatible with those operating under open source licenses such as the GPL. In addition, VMware is committed to supporting any other open virtual machine disk formats broadly adopted by customers and working toward converging on open standards in this area.

"Encouraging the use of a common virtual machine disk format should lead to better interoperability across the industry. VMware's initiative to open up its virtual machine disk format —a format that already is widely used in the industry —is an important development in the virtualization space and will benefit customers and ISVs alike," said Al Gillen, research director of system software at IDC. "We see the broad use of a common virtual machine disk format leading to more products to choose from, along with interoperability across customers' environments."

A virtual machine encapsulates an entire server or desktop environment in a file. The virtual machine disk format specification describes and documents the virtual machine environment and how it is stored. Patch, provisioning, security, management, backup and other infrastructure solutions for virtual machine environments all heavily depend on the virtual machine disk format. Based on this dependency, having an open and unrestricted virtual machine disk format is critical to the broad-based development of new solutions and value-add for virtual environments.

“VMware is offering our virtual machine disk format openly and freely to the virtualization industry,” said Brian Byun, vice president of products and alliances at VMware. “We are doing so because we believe open and freely-useable specifications should increase the availability of complementary products, provide customers unfettered choice and increased interoperability in their virtualized IT environments and further expand the virtualization market which is good for VMware.”

Software vendors like Akimbi Systems, Altiris, BMC Software, PlateSpin, rPath, Surgient, Symantec and Trend Micro are leveraging the VMware virtual machine disk format specification to develop value-added products for customer virtual infrastructure environments.

“As an active member of the VMware Community Source program and a user of the VMware virtual disk format specification, Akimbi is a direct beneficiary of the open approach VMware is taking with its virtual infrastructure software,” said James Phillips, president and CEO of Akimbi Systems. “Free access to VMware source code, APIs and design specifications has enabled us to rapidly innovate on top of the VMware virtual infrastructure foundation. Many of the advanced capabilities of our Akimbi Slingshot Virtual Lab Automation System would have been difficult, or in some cases impossible, to build on a more traditional, closed platform. These capabilities, made possible by VMware’s open approach, translate directly into increased value for our joint customers and channel partners: Akimbi Slingshot runs faster, manages storage far more efficiently and delivers a better user experience when deployed on VMware virtual infrastructure.”

"Our customers run business-critical applications on both physical and virtual systems. To help ensure optimized availability and security of these applications, Altiris management solutions will leverage VMware's new virtual disk format to deliver heterogeneous systems management,” said Dwain Kinghorn, Altiris CTO. “We will offer patch and deployment capabilities for seamless management of physical machines, and online and offline virtual machines to address adoption of VMware technologies on corporate desktops.”

“As a leading Business Service Management provider and the first to provide a federated CMDB to the market, we look forward to VMware opening up the virtual machine disk format specification because it allows BMC Software to offer additional value-added features to our virtualization solutions,” said Kia Behnia, chief architect in CTO office at BMC Software. “Our software can now discover additional resources used by VMware ESX Server and VMware Server and make that information available to our users through our comprehensive existing suite of BMC management solutions for virtualized environments. The new disk format enables new initiatives such as Change and Capacity Management in virtual environments by tracking dependencies between virtual disks and hosted applications and makes these configuration items available to BMC's Atrium CMDB."

"VMware's official release of the virtual disk format specification allows us to enhance the level of integration between PlateSpin OS portability technology and VMware virtual infrastructure," said Stephen Pollack, CEO of PlateSpin. "We will be able to enhance our product's ability to stream servers bi-directionally between physical servers and offline virtual machines, which users can deploy as part of their VMware virtual infrastructure-based disaster recovery strategy."

"The open availability of VMware's virtual machine disk format specification will accelerate the virtualization industry by allowing applications like rPath's rBuilder to generate software appliances in VMware's virtual machine format," said Billy Marshall, CEO of rPath. "These virtual appliances take Software as a Service to the next level, enabling customers to rapidly deploy applications on existing hardware, without the hassles of installation or configuration."

"Surgient has partnered with VMware since 2003 to create virtual lab solutions which automate the provisioning and deployment of virtual infrastructure, benefiting from VMware's openness and strong API set," said Dave Malcolm, vice president of technology at Surgient. "Surgient is already using the VMware virtual disk format specification to provide advanced virtual infrastructure management capabilities and as part of its next platform release available in the coming months. Many of our largest customers have requested these capabilities which are enabled by the open virtual disk format specification. Surgient's customers see direct benefits from VMware's open approach, including faster, more reliable and more efficient virtual labs."

"The VMware virtual machine disk format specification will allow NetBackup to provide more efficient and enhanced data protection for a VMware environment,” said Rob Soderbery, vice president of product management at Symantec. “As the leader in data protection for the enterprise, we are excited to work with VMware to redefine data protection in the virtualized data center.”

"With virtualization becoming more pervasive, it is important for customers to not only secure their physical desktops and servers but also virtual machines," said Punit Minocha, associate vice president of business development at Trend Micro. "By further understanding how VMware virtual machine disks are configured, threat protection companies could potentially build conveniently manageable antivirus functionality into VMware virtual machines."

Additional information on the VMware virtual machine disk format specification is available at

About VMware, Inc.

VMware, an EMC company (NYSE: EMC), is the global leader in virtual infrastructure software for industry-standard systems. The world's largest companies use VMware solutions to simplify their IT, fully leverage their existing computing investments and respond faster to changing business demands. VMware is based in Palo Alto, California. For more information, visit or call 650-475-5000.

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