The core technology of virtualization is relatively simple. Virtualization software turns a server from a box that hosts a single OS or system into a box that can host two or more OSes or systems. By allowing more use from each server, businesses can – like magic – reduce the number of servers they buy and maintain. In some cases, businesses have reduced their servers by a factor of 10 to 1.
But actual implementation isn’t that simple. As business consider implementing virtualization, they need to realize that there are “sweet spots” of this new technology – levels at which implementation makes sense (and levels at which it doesn’t). And there are definitely pitfalls to virtualization.
Will It Work for Us?
Two key factors tend to influence how successful companies are with virtualization, according to Info-Tech, an IT research firm based in Canada that conducted a study of this technology. They are:
• Size of enterprise Very large companies may encounter some headaches in implementation. Virtualization shakes up the existing data system, so the established hierarchies in large enterprises may resist its full use. Conversely, very small firms may not be able to justify the expense. The “sweet spot” is companies with between 100 and 5,000 employees.
Info-tech found a telling fact: while use of virtualization is greater in larger companies, the percentage of their infrastructure that’s virtualized is far lower.
“When small companies do this, they go all in and look at every single x86 server they have,” says Info-tech analyst Matt Brudzynski. “The big companies kind of dabble – they’ll have a department here or a silo there that looks at it.”
• Number of servers While 15 or more servers creates a “sweet spot” of cost justification, a company needs 30 or more servers to fully realize virtualization’s benefits.
Virtualization, of course, doesn’t reduce total software costs (in fact it increases software expense). But IT departments attempting to steer upper management toward virtualization can tout its hardware savings. Info-tech estimates a 40-75% savings in acquiring hardware (fewer servers needed now and in the future). It estimates a 25-50% savings in monthly maintenance costs.
And, virtualization allows the data center to have a “smaller footprint,” by enabling a smaller rack space and lower cooling/electrical costs.
Three Types of Benefits
Info-tech’s research points out that real success with virtualization – truly realizing all its benefits – means success at three levels.
• Tangible benefits The company sees real bottom line costs saving on an ongoing basis. Existing staff can be used more efficiently with fewer boxes to oversee.
• Intangible benefits The company sees a boost in efficiency, business continuity (less server downtime) and disaster recovery (a more robust back-up system afforded by virtualization). Other intangibles include a system that’s easier to manage (it’s viewable from a single console), a separation of hardware and software layers, and control over “server sprawl.”
Additionally, many firms now virtualize their desktops – this enables remote access to desktop images – to better manage security.
• Strategic benefits The company can realistically see benefits to its long term business goals from virtualization. Key point: for many companies, virtualization helps them treat their internal infrastructure as a service rather than a mountain of hardware.
“If you virtualize your environment, you automatically manage your environment as a service because these virtual machines lend themselves to resource pool sharing and management,” Brudzynski says. “You have all these numbers at your fingertips, like how much memory, CPU, and disk space is used. So when a business [or another division in the company] comes to you, instead of buying hardware, you just create them another virtual server, and you know right away how much resources they use so you can charge them based on that.”
As enterprises proceed boldly toward full implementation, they need to be wary of certain pitfalls:
• Staff Reductions (Not) Don’t count on much (or any) staff reduction from virtualization. While the firms that Info-tech surveyed were able to use fewer boxes, the IT staff overseeing these systems still had plenty of responsibilities.
• Huge Consolidation (Maybe Not) Don’t assume you’re going to realize a gargantuan server consolidation from virtualization – although you might. Some IT departments dream of a 10 to 1 or even 12 to 1 (or more) reduction in servers. Realistically, among the firms Info-tech spoke with, average consolidation was in the 6 to 1 range.
• I/O Bottlenecks It’s possible that your servers will encounter bottlenecks in their I/O capacity. Sure, virtualization allows you to load up a single server with multiple OSes and a handful of muscular apps. But at some point, that server’s I/O capacity could run into a bottleneck if you try to route too much data, too fast, through it.
• Licensing headaches “If you have virtualization running on a [four-processor] server, you may have a virtual machine using one processor,” Brudzynski says. “But when you go to Oracle and say ‘I’d like to buy a license for my processor, they’ll say ‘Well, how many are in the machine?’ So even though you may only be using one, they’ll charge you for four.”
In short, “It’s possible in some cases that when you virtualize, if you’re not careful, your license costs may go up.”
Next page: Saving Money Requires Expenditure
While virtualization should save money, it also requires investment. In particular: host machine hardware. Many managers squawk at the idea of having to buy new servers to implement virtualization. Isn’t this technology about reducing servers?
But in fact, many companies opt to buy a few (or more) new servers. Because if you’re asking one server to do the work of six, that one server has to be a pretty beefy box.
“Unless you’re lucky enough to have that honkin’ server already, what you’re going to end up doing – and we’ve talked to customers who’ve done this – is end up putting two or three servers on to one [server], then two or three on to another,” Brudzynski says. While these companies saw about a 3 to 1 consolidation ratio, “if they bought new [servers], they could have done 10 to 1 or higher.”
And there are other costs, including virtualization software, a SAN (which might not be needed), staff training, and possibly consultant’s fees. On an ongoing basis, the software will need maintenance, and as staff turns over, a business will need to cover training costs. (Plus, hiring staff that’s virtualization-savvy might require slightly higher salaries.)
Taking the Plunge: The 12-step plan
For companies considering the plunge in to virtualization, Info-tech identifies twelve critical steps in planning and implementation:
1) Determine the approach; 2) Develop the business case; 3) Gain buy-in from management; 4) Capacity planning and benchmarking; 5) Select hardware; 6) Select software; 7)
Resourcing; 8) Application sequencing; 9) Testing; 10) Centralize/consolidate; 11) Migrate; 12) Monitoring and expansion.
Regarding step No. 2, “Develop the business case,” Brudzynski notes, “that entire case is just based on your hardware savings – the fact that you don’t have to buy servers. Although there are intangible benefits, you don’t need those,” to prove that virtualization saves dollars.
Step No. 4, “Capacity planning,” is a particularly crucial step, warns Brudzynski. “If you don’t get that right, you’re going to go through a lot of trial and error when you try and figure out, ‘Should I have five virtual servers on this one [real server], or should I have three, or six?’ If you do a proper capacity plan you can avoid all that and get it closer to right the first time, as opposed to going back and forth, and having your users complain that it’s too slow.”