The vCenter Server design includes the design for all the vCenter Server instances. For this design, determine the number of instances, their sizes, networking configuration, cluster layout, redundancy, and security configuration.

A vCenter Server deployment can consist of two or more vCenter Server instances according to the scale, number of VMs, and continuity requirements for your environment.

Protecting the vCenter Server system is important because it is the central point of management and monitoring. You can protect vCenter Server according to the maximum downtime tolerated. The following methods are available to protect a vCenter Server instance:

  • 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 Management vCenter Servers

Attribute

Specification

Appliance Size

Small (up to 100 hosts or 1000 VMs)

Number of vCPUs

4

Memory

19 GB

Disk Space

528 GB
Table 2. Recommended Sizing for Compute vCenter Servers

Attribute

Specification

Appliance Size

Large (up to 1,000 hosts or 10,000 VMs)

Number of vCPUs

16

Memory

37 GB

Disk Space

1,113 GB

TLS Certificates in vCenter Server

By default, vSphere uses TLS/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).

Table 3. Recommended vCenter Server Design

Design Recommendation

Design Justification

Design Implication

Deploy two vCenter Servers. One to support the management workloads and another to support the compute workloads.

  • Isolates vCenter Server failures to the management or compute workloads.

  • Isolates vCenter Server operations between the management and compute workloads.

  • Supports a scalable 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 the separation of maintenance windows.

  • Supports separation of roles and responsibilities to ensure that only administrators with proper authorization can attend to the management workloads.

  • Facilitates quicker troubleshooting and problem resolution.

Requires licenses for each vCenter Server instance.

Protect all vCenter Servers by using vSphere HA.

Supports the availability objectives for the vCenter Servers without 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.

Use an SHA-2 or higher algorithm when signing certificates.

The SHA-1 algorithm is considered less secure and is deprecated.

Not all certificate authorities support SHA-2.