Utilising Virtualisation For Disaster Recovery - Part 2

The starting point is to look at the problemsa certain investment of time and skill in the
associated with traditional business continuity andexecution, but a significant reduction all the same. Its
disaster recovery strategies. At enterprise,this inherently efficient portability that has got people
multi-national level, it is estimated that almost 80 perexcited because here at last is a way to break the
cent of the Disaster Recovery budget is given overstranglehold of the one-to-one server relationship.
to the protection of just 20 per cent of the totalPortability is the essential by-product of the real
server network, namely their most business-critical‘virtue of virtualisation' – encapsulation. You
servers. It's an understandable risk managementcan encapsulate an operating system, software, and
trade-off.its data into the equivalent of a single discrete file, or
In an ideal world, organisations would want to protectworkload; you can then transmit this workload to a
all server workloads, with Disaster Recoverysecondary location, create a bootable backup on a
procedures geared to rapid recovery with a high levelvirtual recovery platform and get your users back
of data integrity – they would look to a separateonline in a matter of hours, or less. Suddenly,
data centre or centres and maintain mirroredorganisations don't have to be shackled by the
environments, perfectly synched and ready to go.heterogeneity of disparate servers, operating
But the reality of those hot standby environments,systems, applications and data sets – instead
and the high end server clustering and data replicationthey can leverage the homogeneity implicit within
that powers them, is that you need a one-to-oneportable workloads.
hardware relationship and software redundancy: youThey can now move and replicate complete
must have exactly the same server configuration atworkloads as discrete, aggregated units, detaching
the discrete data centre as at the primary site withthem from their native hardware configurations and
precisely the same operating system versions,directing them between physical and virtual hosts as
licenses and patches installed. It's a costly and aneeds dictate – from physical to virtual, virtual to
complex undertaking that is justifiable only in relationphysical, physical to physical etc. One could argue that
to ultra mission-critical servers; the rest of the ITfor a hard-pressed IT team the cost savings are
estate will have to make do with more sustainablevery much secondary to the agility and flexibility
but lower – and therefore more risky – levelsafforded to them in dealing with unpredictable service
of protection. Think of it in insurance terms: youdisruptions. That's the trouble with disaster recovery
arrange a reasonable level of cover at a reasonable– most people have at least got beyond the
price and you accept the risk/cost compromise; it's‘it'll never happen to me' ostrich act but find
only when you want belt and braces cover for thosethemselves stymied by an endless array of
specified high value items that the premiums shoot‘what could happen' scenarios and crafting a
into ‘how much?' territory.suitably risk-balanced response. Disaster Recovery
Against that backdrop it's easy to see whatcan come out of the mundanely routine – the
triggered the interest in virtualisation as a newhardware or circuit failure, the software glitch, plain
Disaster Recovery dimension. Even by the crudestold human error – or the spectacularly
measure, replicating five production servers on adevastating – the fire, the flood, the bomb, but
single server running multiple instances of a virtualeither way you need to be adequately prepared for
operating system is going to reduce costs – notwhether it is just one server that's affected, a single
a directly correlating 80% reduction and not withoutsite or the whole corporate wide area network.