A succesful virtualisation strategy needs strong discipline

Companies are buying virtualisation in a bid to make their operation more efficient.

Scott Herold has seen it all before. Companies buy virtualisation in a bid to make their operation more efficient. Then admins start creating virtual machines at the drop of a hat, to satisfy the whims of developers and other users who need a clean OS image, just for a minute.

"One customer said they had 1,500 virtual machines, and went back to check the due diligence they did during physical-to-virtual migration, and they have only 500 Virtual machines with a valid business case," says the lead architect for the virtualisation business at Quest Software's Vizioncore subsidiary.

Just because you're virtualising everything on a server doesn't mean that you can dispense with systems management discipline. Abstracting logical assets from physical ones makes them more prone to proliferation and movement, and datacentre managers who have to look after those physical resources must be sure that they're not overtaxed. Add to that the need to fold virtualised environments into a disaster recovery strategy, and it's easy to see how unprepared IT departments who thought they were buying the answer to all their problems end up with a logical infrastructure spiralling out of control.

VMware, the poster child of modern virtualisation industry, has been busily releasing products that help to integrate its virtualisation offering into the datacentre. "It's taken it a while to admit that it isn't the entire stack - that it's more middleware than an end-to-end solution," says Chris Wolf, a senior analyst at the Burton Group.

Backup and patch management

Nevertheless, the company is trying hard to cover all the management bases. Its VMware Infrastructure, designed to manage the virtual infrastructure, comes in three editions depending on company size. All of them feature backup and patch management capabilities, but there are extras, bundled as the edition becomes more sophisticated. The standard edition adds in VMware High Availability, which provides failover services for virtual machines. The Enterprise edition includes power management features, along with VMotion, a six-year-old product providing dynamic resource scheduling services.

"The first-use case for server virtualisation was consolidation," explains Lionel Cavalliere, senior product marketing manager for EMEA at VMware, who says that VMotion took things a step further by enabling physical servers to work together and provide virtual machines with extra support. "It's a technology allowing live migration from one physical machine to another, without any loss of transactions," he says. That makes it useful for routine maintenance and also for managing server load more effectively.

But even though it has the advantage of selling the hypervisor as well as the software to manage it, VMware faces stiff competition. Other firms are jockeying for position in the virtualisation management market. Products such as Quest's vOptimizer Pro help to mitigate Virtual machines sprawl by regularly monitoring Virtual machines usage against pre-defined criteria, making it easier for administrators to rein in the Virtual machines they no longer need.

Incremental replication

Quest is also one of several companies providing image-level backups for Virtual machines. Virtualisation can also be used to enhance existing disaster recovery practices, points out John Stetic, director of product management at Novell, who came to the company when it purchased virtualisation management company Platespin. "We can replicate into an offline virtual machine. So now you have not only a backup repository of your production workload, but you can also use that backup repository as a recovery environment." The company packaged this up into an appliance with its Forge product. It supports incremental replication roughly every six minutes. "We're not a replacement for a clustering solution," he adds.

Neverfail sells products designed to back up specific Windows-based applications such as Exchange and Sharepoint. "We're a solution for high availability disaster recovery that embraces both the physical and virtual worlds," says senior vice-president Andrew Barnes. "It lets you protect multiple physical machines, maybe one running Exchange, and one running SQL, with a single VMware machine providing the secondary failover server capability." With Neverfail's product you don't need shared storage unlike VMware HA.

What's missing now is a robust integration strategy between some of these products and those sold by the larger systems management vendors, such as Tivoli and Openview. "I don't think it has articulated their management integration story as well as it could," says Burton's Wolf in regard to VMware. Nevertheless, the company is making strides in this area. It signed a partnership to integrate support for its virtualisation system into BMCs management software. It has also published the VI API, which allows other programs to communicate with the VMware Infrastructure platform for the control of Virtual machines.

As virtualisation gains mindshare, then, the tools and techniques to manage it are evolving nicely. Customers would do well to deploy these if they are to get the full benefit of virtualisation and minimise the downsides associated with sloppy usage.

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