Page 78 - How Cloud Computing Is Transforming Business and Why You Cant Afford to Be Left Behind

MANA GEMENT STRATEGIES F O R THE CL OUD R EV OL UTION

were available, again without interrupting the operation of
the VM as far as its end users were concerned.
Virtualization gives the cloud data center manager an ar-
senal of weapons with which to attack the problem of balanc-
ing his systems against demand and dividing up resources.
Virtualization to a great extent breaks the hard boundaries

that used to surround each physical machine and substitutes
a more plastic resource for the cloud operations manager.
He can mold that resource with more flexibility than his pred-
ecessors could. In the cloud, where he needs to maintain the
illusion of unlimited resources for users, the operations man-
ager has ample cause to enlist the virtual machine manage-
ment console and view all his servers through it.

Managing by Moving Things Around

Two or three years ago, the notion of moving a running ap-
plication would have struck many professional IT managers
as dangerous, if not preposterous, because of the potential
for a crashed process. But today the virtual machine’s ability
to conduct a “live migration,” or a move from one physical

server to another, while running is accepted as a reliable data
center technique. Not that it doesn’t still inspire a bit of awe.
One IT manager said that when he showed end users how
he could move their running virtual machines without dis-
ruption, it appeared to confer on him “godlike” powers, in the
observers’ eyes.

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