The vCenter Server design encompasses all the vCenter Server instances, including the number of instances, their sizes, networking configuration, vSphere cluster layout, redundancy, and security configuration.

According to the site design, overall scale, number of VMs, and continuity requirements for your environment, a vCenter Server deployment for the Telco Cloud consists of two or more vCenter Server instances with one vCenter for the Management Domain and at least one additional vCenter for the workload domain.

The vCenter Server system is the central point of management and monitoring. Use the following methods to protect vCenter Server according to the maximum downtime tolerated:

  • Automated protection using vSphere HA

  • Automated protection using vCenter Server HA

vCenter Server Sizing

You can size the resources and storage for the Management vCenter Server Appliance and the Compute vCenter Server Appliance according to the expected number of VMs in the environment.
Table 1. Recommended Sizing for the Management vCenter Server

Attribute

Specification

Appliance Size

Small (up to 100 hosts or 1000 VMs)

Number of vCPUs

4

Memory

21 GB

Disk Space

579 GB
Table 2. Recommended Sizing for Workload Domain vCenter Servers

Attribute

Specification

Appliance Size

X-Large (up to 2,000 hosts or 35,000 VMs)

Number of vCPUs

24

Memory

59 GB

Disk Space

2,283 GB
Note:

vCenter sizing depends on the site or workload domain scale.

TLS Certificates in vCenter Servers

By default, vSphere uses TLS or SSL certificates that are signed by VMware Certificate Authority (VMCA). These certificates are not trusted by end-user devices or browsers. As a security best practice, replace at least all user-facing certificates with certificates that are signed by a third-party or enterprise Certificate Authority (CA).

vCenter RAN Considerations

In a RAN-only deployment, the ESXi hosts are added to vCenter as standalone hosts. Scaling of RAN deployments is significant in a domain.

Using dedicated vCenter Servers for RAN deployments with a high host count has the benefit of separating lifecycle management of RAN and Core workload domains. This approach requires additional vCenter deployments and is determined based on the overall Telco Cloud design considerations and constraints.

Recommended vCenter Designs

Design Recommendation

Design Justification

Design Implication

Deploy at least two vCenter Server systems:

  • One vCenter Server supports the management workloads

  • Another vCenter Server supports the compute workloads

  • Isolates vCenter Server failures to management or compute workloads.

  • Isolates vCenter Server operations between management and compute workloads.

  • Supports a scalable vSphere cluster design where you might reuse the management components as more compute workload domains are added.

  • Simplifies capacity planning for compute workloads because you do not consider management workloads for the Compute vCenter Server.

  • Improves the ability to upgrade the vSphere environment and related components by separating the maintenance windows.

  • Supports separation of roles and responsibilities to ensure that only authorized administrators can handle the management workloads.

  • Facilitates quicker troubleshooting and problem resolution.

  • Requires licenses for each vCenter Server instance.

  • Deployment location of vCenter Server depends on the centralized or multi-site deployment design.

Protect all vCenter Servers by using vSphere HA.

Supports the availability objectives for vCenter Server without the required manual intervention during a failure event.

vCenter Server becomes unavailable during the vSphere HA failover.

Replace the vCenter Server machine certificate with a certificate signed by a third-party Public Key Infrastructure.

Infrastructure administrators connect to the vCenter Server instances using a web browser to perform configuration, management, and troubleshooting.

The default certificate results in certificate warning messages.

Replacing and managing certificates is an operational overhead.