A Two-Pod configuration provides a compact footprint design choice for telco workloads.
Footprint
High level of resiliency is provided by using four-host clusters with vSAN storage in the initial deployment. Four-host clusters also ensure a highly available Management Pod design, because clustered management components such as vCenter Server active, standby, and witness nodes can be placed on separate hosts. The same design principle is used for clustered OpenStack components such as database nodes.
When using high-end class servers, this design maximizes the resource utilization and densification of workloads and Edge Nodes in the same Pod.
Scale Flexibility
The initial number and sizing of management components in the Management Pod should be planned in advance. As a result, the capacity that is requirement for the Management Pod can remain steady. When planning the storage capacity of the Management Pod, the CSP should consider the operational headroom for VNF files, snapshots, backups, VM templates, OS images, upgrade and log files.
The collapsed Edge & Resource cluster sizing will change according to the VNF and networking requirements. When planning the capacity of the Edge & Resource Pod, tenants must work with VNF vendors to gather requirements for the VNF to be deployed. Such information is typically available from the VNF vendors as deployment and sizing guidelines. These guidelines are directly related to the scale of the VNF service, for example to the number of subscribers to be supported. In addition, the capacity utilization of Edge Nodes must be taken into consideration, especially when more instances of Edge Nodes are deployed to scale up as the number of VNFs increases.
When scaling up the Edge & Resource Pod by adding hosts to the cluster, the newly-added resources are automatically pooled, resulting in added capacity to the compute cluster. New tenants can be provisioned to consume resources from the total pooled capacity that is available. Allocation settings for existing tenants must be modified before they can benefit from the increased resource availability.
Operations Management
The Management Pod provides centralized operation function across the deployment topology, be it a single or distributed data centers.