Appendix D: Capacity Management
vCloud-Specific Capacity Forecasting – Demand Management
Capacity forecasting consists of determining how many organization virtual datacenters are expected to be provisioned during a specific time period. Capacity provisioning is concerned with determining when vCloud infrastructure components must be purchased to maintain capacity. From a financial budget perspective, the procurement of the vCloud infrastructure requires more planning and understanding of customer future requirements.
VMware recommends performing two forecasting functions over time.
Capacity Trending
– Using historical organization virtual datacenter
capacity and utilization data, it is possible to predict future capacity requirements.Demand Pipeline
– Understanding future customer requirements via the sales pipeline provides the necessary information to understand future capacity requirements, as well as knowledge of marketing/business development functions bringing new service offerings to market.
Initially, no historical utilization metrics are available, and thus it is not possible to perform capacity trending for some period of time. During this initial period, a good understanding of the customer demand pipeline needs to be established. Over time, this pipeline can be combined with trending analysis to more accurately predict capacity requirements.
The customer demand pipeline must be established in conjunction with the service provider’s sales teams, or lines of business (LOB) if a private vCloud, so future vCloud capacity requirements can be determined. This demand pipeline must contain information of all known new customers, expansion of existing customer organization virtual datacenters, projected sizing metrics, plus any new service offerings that are in development. The forecasting plan must fit both the budgetary cycle and the procurement and provisioning timeframes. For example, if a quarterly budgetary cycle exists, and the procurement and provisioning timeframe is one month, it is necessary to have a pipeline of at least four months to make sure all requests in the pipeline can be fulfilled.
Over time, capacity trending can be used to assist with the forecasting of organization virtual datacenter provisioning needs. It uses historical information to determine trends and validates the organization virtual datacenter forecast based on demand pipeline data.