Virtualization is heralded for reducing server sprawl and optimizing utilization. Yet deployed incorrectly, it can wreak havoc on an enterprise. With virtualization, enterprises have the power to move resources in an instant, but the wrong move can actually hinder user performance and increase management costs. Knowledge Center contributor Justin Steinman explains the steps necessary to successful virtualization in a mixed data center environment.
As heterogeneous data centers become more complex, so does the scale of the
virtualization project. Managing not only multiple platforms but countless
hypervisors, operating systems and even virtualization tools causes exponential
levels of complexity. In addition, virtual machines can rapidly proliferate,
leading to poor resource utilization and excessive IT overhead.
Enterprises can, however, adopt virtualization management practices that
transform the IT environment from a landlocked resource into a model of utility
computingby following what I believe are the top 10 steps to successful
virtualization in a mixed data center environment:
Step No. 1: Take it slow
Are you anxious to reap the full benefits of virtualization and under
pressure to rein in costs? Avoid the leap before you look scenario.
Virtualizing all at once is bound to cause unforeseen problems. Take small
steps first, and then monitor resulting performance and management issues. Then
move on to more virtualization opportunities.
Step No. 2: Evaluate current server workloads
Gaining a thorough understanding of server workload is a critical first step
to determining which applications should be virtualized. The best candidates
for virtualization are applications running on Web, infrastructure or
application servers. However, applications with high performance sensitivity or
very high I/O requirements would not do well in a virtualized environment.
Gather detailed data for all hardware and software assets across the data
center, and analyze workload utilization to develop optimal server
consolidation plans. Then use the server utilization data collected to generate
a hardware utilization report that identifies workload and resource mismatches
such as under- or over-utilized servers.
Step No. 3: Analyze the complete workload life cycle
Analyzing workloads at a single point in time is not particularly helpful,
since workloads can vary drastically by time of day, season or other variables.
Record utilization data over a significant time period such as a financial
quarter end to ensure that all ebbs and flows in resource utilization are
captured accurately. You can then develop a workload profile that provides a
clear picture of server utilization trends and anomalies in CPU, disk, memory
and network utilization rates. This brings consistency and predictability to
workload management. It also reveals the necessary trend analysis data to
automate provisioning and capacity planning.
Step No. 4: Apply what-if modeling
Use what-if modeling to find the best combination of hardware and virtual
hosts to maximize utilization, avoid resource contention and forecast future
workloads. It is also prudent to run scale-up and scale-out scenarios to ensure
sufficient capacity for current and future needs without over-provisioning the
consolidated environmenta common and costly problem.
Step No. 5: Check your management tools
Many virtualization management tools only allow you to manage one type of
hypervisor. If you have completely separated your virtual server farm and physical
data center, you might be fine with separate virtualization tools. However, for
those organizations looking to create and maintain a dynamic data center where
they can easily move between physical and virtual machines, one tool would be
advisable.
Step No. 6: Test before going live
Test virtualized servers to ensure application performance doesn't slow down
due to combining too many resource-intensive applications on the same physical
server. This is where workload migration tools come in handy. Theyre used to
decouple data, applications and operating systems from the underlying hardware
and stream them to any physical or virtual platform. This makes it easy to
deploy virtual machines to test servers before going into a live production
environment.
Step No. 7: Take advantage of dynamic provisioning
The act of virtualization only takes us so far. The next step is to adjust
processing power on demand. For example, you could set a threshold so that when
usage of a critical application hits 80 percent, a new server is automatically
brought online. This type of intelligent resource management gives
organizations the ability to design data centers that respond to their business
needs.
Case in point: A large educational organization virtualized its entire Web
front end. Through virtualization analysis, it discovered one site had higher
traffic in the early morning while another experienced spikes in the afternoon.
By dynamically reallocating resources based on time of day, it was able to
reduce its server footprint by 80 percent, hardware costs by 30 percent and the
entire IT budget by 18 percent.
Step No. 8: Continuously analyze
Virtualization isnt a one-time endeavor. Its a strategy for ensuring the
continuation of optimal system utilization and performance. Workloads and
resource demands change over time, necessitating periodic rebalancing to keep
the data center running in an optimal state. Fortunately, there are new
virtualization analysis tools that make it easy to continuously monitor, move
and consolidate workloads.
Step No. 9: Gain visibility
Use management tools to gain a clear view of the total virtual machines on
each server, what workloads are being added and at what rate. This vastly
improves resource planning. Moreover, it gives companies the ability to track
workloads and allocate IT charges to business units based on actual disk, CPU
and network usage.
Step No. 10: Leverage disaster recovery scenarios
Employing virtualization solutions for business continuity gives organizations
a way to get more out of their virtualization investment. The portability of
virtualization also lends itself to more efficient disaster recovery. All
server workloads, whether theyre on physical or virtual machines, can be
duplicated to virtual machine backups. If an outage occurs, the workloads
simply fail over automatically to the duplicate virtual machines.
Conclusion
As organizations delve further into virtualization, its easy to fall into
many of the same traps that exist as physical environments. Better capacity
planning and modeling are necessary to avoid resource bottlenecks and virtual
sprawl. Virtual servers require a new management approach that encompasses
upfront planning, workload life cycle analysis and continuous monitoring.
Ultimately, those who take these logical steps can fulfill the promise of
virtual infrastructure.
Justin Steinman is vice president of solution and product marketing at Novell.
He is responsible for Novell's go-to-market strategy, messaging,
campaign planning and alliance marketing. He can be reached at jsteinman@novell.com.