The logical compute design defines the capacity and performance requirements for CPU and memory resources.
The logical compute design specifications are as follows:
- Total CPU resources: 167 GHz
- Total memory resources (25% TPS savings): 657 GB
- Number of virtual machines per host: 20
- Number of hosts required (N+2): 9
- CPU resources per host: 23.8 GHz
- Memory resources per host: 94 GB
The hardware that's selected for the physical compute design must satisfy the resource requirements of the logical compute design. These resources include the CPU and memory resources. The physical hardware that's selected must also be able to support the network and storage connectivity resources that are defined in the logical network and storage design.
Along with the design requirements and constraints, the factors that influence the physical compute design are as follows:
- The required CPU resources
- The required memory resources
- The vCPU-to-CPU-core ratio
- The processor manufacturer and model
- The number of hosts required: scale up or scale out
- The host form factor: rack or blade
- The number of PCI slots
- The number and type of network uplinks
- The number and type of Host Bus Adapters (HBA)
- Power, space, and cooling requirements
The following diagram is an example of a physical compute design that uses the Cisco UCS blade platform; the blades have been configured to support the logical requirements, and multiple chassis have been chosen to eliminate single points of failure:
The following diagram is the rear view of the Cisco UCS blade solution and shows the supporting components, including the connectivity of the chassis to the fabric interconnects.
The diagram also shows connectivity between the fabric interconnects and the network and storage. Multiple links to the chassis, network, and storage not only provide the capacity and performance that are required, but also eliminate single points of failure, as shown in the following diagram:
