Where do you start when designing Resource Pools in an empty VI?
a) Create pools based on Development, Test & Live then divide total resource by 3?
b) Divide total resource by a rough split of your planned P2V phasing?
c) Create pools for logical grouping of VMs?
d) Group by vCPU or RAM allocation?
etc… Anyway, I think I’ve painted the picture. So what’s the answer?
Simple, understand the business needs.
“But that’s not a technical answer!”
A Virtualised Infrastructure is really no different to any other service provision. If you’ve just moved home you wouldn’t ring up your local water authority and request ‘x’ amount of water must be provided to your home. You’d say “I’d like water please and let me know how much I owe you for a residential supply.”
Why not apply this methodology to service provision?
Example, you need a single SMTP relay running under IIS 6, anticipated 10k mail a day. POC this with a test tool, review utilisation demands. Snapshot results, add a bit more based upon forecasted peeks, done. The project now requests what it needs to deliver the requirements.
Resource pool decisions don’t necessarily have to be final. Shape the delivery of services around business demand. Force new projects to fully comprehend their requirements and impact.
We’re in a strong position using a Virtualised Infrastructure:
- Resource can be ramped up, down and constrained. Whereas fast executed projects using physical service provision can be disastrous if poorly executed.
Resource allocation with a sliding scale – it’s the way forward.
