Tesco began investigating virtualization as an alternative to adding more physical servers to handle its growing capacity demands as well as fulfilling its community commitment to reduce carbon emission levels. While adding physical servers would require an increase in power and cooling, virtualization has better equipped Tesco to hit its target of reducing carbon emissions from its UK data centres by 20 percent.
"After conducting a major evaluation of virtualization providers, we went with Citrix based on the strength of the Xen technology, the ability XenServer has to provide high levels of performance for heavy duty 64-bit applications, its licensing model and its UK-based engineering team - decisions that have already paid off for us", stated Nick Folkes, IT director at Tesco. "The virtualized RTS environment uses less than half of the energy of the physical bare metal equivalents, which supports our CO2 targets and means we have already saved a significant amount on our electricity bills. We're running far more efficiently and the ongoing management of the environment is much simpler. While our primary goal in working with Citrix and HP was to create a more flexible IT infrastructure, the consolidation benefits are significant."
After the success of the initial project to virtualize RTS, Tesco has continued to deploy XenServer for its major server consolidation project. Citrix is working closely with Tesco to virtualize 1,500 physical servers on XenServer, including 80 Citrix XenApp servers. This is already bringing greater efficiencies to the way applications are delivered to each Tesco store. Tesco is aiming for a conservative 10:1 consolidation ratio for physical to virtual servers and is hitting 70 percent CPU utilization on the servers, versus the previous six percent. From an operational perspective, Tesco has been able to utilize the XenMotion live migration feature of XenServer to migrate virtual machines to other physical hardware, with zero downtime, allowing patches and updates without disrupting users. Subsequently, Tesco has been able to remove its clustering back-up technologies and replace them with virtual servers. And, since XenMotion does not tie the resilience to a particular platform, Tesco has reduced its back-up server to live server ratio from 1:2 to 1:6.
XenServer is running on 64-bit HP ProLiant BL680C G5 blade servers with HP StorageWorks XP24000 SANs for enterprise-wide storage. HP's four-socket, four-core machines for blade servers were a clear differentiator for Tesco at the time of purchase. Resilience through the solution ensures there is no single point of failure, which is essential for a business-critical application like RTS. And because Citrix licenses for advanced virtualization management capabilities are charged per server instead of per socket, Tesco is not penalized for using larger blade servers.
"RTS is a mission-critical system for Tesco with very high throughput of transactions based on Microsoft IIS, BizTalk and SQL, so it requires the highest standards in processing power", stated John Glendenning, vice president, OEM sales, at Citrix. "Virtualization is key to providing a cost-effective, efficient and future-proof data centre, and XenServer has been key to helping Tesco achieve its ambitions for a virtualized environment that supports mission-critical systems. The Citrix Delivery Center approach has enabled Tesco to create a customized virtualization strategy, using XenServer and HP for integrated server virtualization and XenApp and XenServer for the most efficient delivery of applications to stores across the country. The strategy is helping Tesco achieve its operational objectives - ultimately, it helps Tesco provide a better service to its customers."
"Tesco can achieve immediate cost savings and long-term business growth goals by virtualizing their key business applications with HP BladeSystem Servers running Citrix XenServer", stated Jim Ganthier, vice president, Marketing, ESS Infrastructure Software and BladeSystem, HP. "The combination of HP BladeSystems and Citrix technology helps companies like Tesco strategically spend and carefully prioritize their technology investments - a critical task in the current economy."
The Citrix solution dynamically provisions both virtual and physical servers, resulting in increased IT responsiveness and agility by enabling capacity on-demand, and the ability to dynamically manage provisioning for disaster recovery and business continuity. In addition, XenServer is optimized for XenApp, providing customers with enhanced scalability and faster performance for Windows application delivery running in a virtualized environment.
Citrix and HP have been collaborating since March 2008 to help customers deploy and manage virtualized environments faster and more easily than ever before.