Virtualisation technology, which offers users the
ability to pool their hardware resources, is playing a major role
in making IT more flexible and cost-effective.
Virtualisation software has allowed many users to reduce their
hardware assets, or use them more efficiently, by running multiple
“virtual machines” side by side on the same hardware, emulating
different components of their IT systems.
Virtualisation has now moved beyond mainframes and servers and
has found its way into applications, networks and storage, among
others.
Galen Schreck, senior analyst at
Forrester Research, said mainframe users were
the first to adopt server virtualisation. In fact, the technology
has been around for decades.
Following the mainframe, Unix suppliers such as IBM, Sun
Microsystems, and Hewlett-Packard began offering virtualisation
technologies. “These have matured into their current line-ups of
logical partitions, Solaris containers and Virtual Server
Environment, respectively,” Schreck said.
More recently, VMware’s ESX Server, Microsoft’s Virtual Server,
and open source supplier XenSource’s Xenenterprise have lowered the
cost of virtualisation because they run under Windows and Linux,
and on commodity Intel or AMD x86 servers.
“Many firms attribute their adoption of virtualisation to server
consolidation, but an equivalent number are using the technology to
make their server environments more flexible and agile in a manner
once exclusive to Unix-based platforms,” Schreck said.
Users are beginning to reap a range of benefits from
virtualisation which go beyond the cost savings of server
consolidation.
For example, the Association of Teachers and Lecturers (ATL) is
using virtualisation to not only cut hardware costs, but also to
recover quickly from systems failures and maintain business
continuity.
The ATL is using VMware’s ESX Server virtual environment and its
VMotion tool. VMotion can move an entire virtual machine
instantaneously from one server to another, and makes use of
virtual storage, applications and networking. The network is also
virtualised by ESX Server, so the virtual machine retains its
network identity and connections after the migration process.
Ann Raimondo, head of IT at the ATL, said virtualisation has
halved the association’s server count from 22 to 11 through
consolidation, cut its operational expenses and capital costs, and
has given it a single view of all its computing resources.
Virtualisation has also allowed the ATL to restore systems
quickly after a failure because they are backed up to servers
rather than tapes stored at an off-site datacentre. The
virtualisation technology can virtualise processors, network
interface cards, ports and discs, so a back-up can be up and
running in minutes.
Another common use of virtualisation is to test and develop
applications in a secure environment without affecting the main IT
systems. HM Revenue & Customs is using a software
virtualisation platform to simplify and accelerate the deployment
of about 600 wide-ranging applications used by its 70,000
employees.
HMRC’s main reason for deploying its virtualisation platform –
Softricity’s Softgrid, running on HP hardware – is to reduce its
testing and deployment costs and to port its applications over to a
Citrix thin-client system.
The big drawback of virtualisation is that users could face
serious performance issues, as fewer servers do more work. Although
virtualisation technology lets users operate fewer servers, it does
not make programs run faster.
Microsoft, for example, advises users to increase the memory,
processors and hard drive speed of their servers, and make other
technical adjustments to compensate for the additional workloads
that virtualisation creates.
Virtualisation also means licensing issues. The technology
allows applications to run independently of the hardware, which can
contravene some licence agreements.
Neil Macehiter, partner at analyst firm Macehiter Ward-Dutton,
said, “Server virtualisation is undoubtedly forcing software
suppliers to reappraise their licence models. The licensing models
of many software suppliers do not allow for flexibility.”
But there are signs of change from the supplier community. At
the end of last year, Microsoft allowed users of Windows Server
Enterprise and Datacenter to run up to four instances of the
software under products such as VMware Server and ESX Server at no
additional cost.
However, this permission does not cover older Microsoft
operating systems. In fact, users would be wise to check the terms
and conditions of their other operating systems and applications
before they virtualise them.
But in the face of the technology’s potential benefits, these
obstacles appear minor: it looks as though virtualisation is here
to stay.
Case study: HBOS banks on virtualisation
Banking group HBOS launched a massive virtualisation strategy in
2003 that will eventually virtualise storage, local area networks
and application servers.
HBOS’ IT decision was driven by business requirements, which
included supporting business growth and controlling and reducing IT
costs through optimisation, integration, virtualisation and
automation.
HBOS virtualised its wide and local area networks first, then
reorganised its application servers by using Microsoft Virtual
Server to virtualise its IBM Aix mainframe and HP Windows/Itanium
servers.
HBOS is reordering 1.7 petabytes of storage to access and manage
the space as virtual pools of resources. To do this, the bank is
implementing Emulex’s Lightpulse LP11000 host bus adapter (HBA)
equipment, along with Virtual Storage Manager software and storage
systems from StorageTek.
The HBA is a key part of the virtual storage system. It sits on
the host server to control the transfer of data between the host
and the target storage device in an intelligent way.
www.virtualization.info
IBM and Intel team up on virtualisation
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