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VMware vSphere Enterprise Plus: An El Reg deep dive

Trevor Pott feels the big business end of virtual machine giant

So you bought a couple of nodes last month - what happens when you order hundreds?

vMotion, Storage vMotion, DRS, distributed power management (DPM), host profiles and auto deploy are what I call "coalface tech". They are not technologies that reduce capital expenditure (capex) or provide a layer of risk management. They are the operational (opex) features that make the lives of systems administrators better. Selling opex to the pointy-haired boss is traditionally much harder than selling capex.

As the widgets that let us move VMs from one system to another without turning them off, vMotion and Storage vMotion should sell themselves. Hardware dies. Sometimes you have to upgrade a system to get better performance. In both cases the ease of vMotion saves an awful lot of systems administrator time. Your time – and the cost of system downtime – is worth more than the licences.

Indeed, I'd go so far as to say it justifies virtualisation all on its own, without any of the consolidation arguments that have been used for the past decade. Then again, I'm a sysadmin; I naturally favour opex arguments over capex ones.

DPM takes the chore of moving VMs to the smaller required number of hosts and powering off the unneeded hardware off of our hands. DPM could be sold as capex – lower power bills - but in reality, we'd have just written scripts to do what it does anyway. DRS is the automated load balancer; a function that VMware admins not blessed with Enterprise licences rapidly tire of. Even with the small networks I run, load balancing takes up far too much of my time; at scale, the opex savings could prove quite significant.

Host profiles and auto deploy disconnect the rack monkey from the hypervisor. Slap the first host onto your network and configure it the way you want. Save that configuration as a host profile; repeat for every host type you have. Set up auto deploy and not only will vSphere install the hypervisor on each new server it discovers, it will install the correct configuration as determined by your pre-set host profile. This isn't worth the cost of the licence if you only buy a host or two a year; it becomes mandatory if you start buying them by the hundreds.

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