The management components of a virtual environment can be resource intensive. If you are running vCenter and its dependencies as virtual machines in the same cluster as the cluster managed by the vCenter server, the resources required by the management infrastructure must be factored into the capacity calculations of the logical design. Creating a separate management cluster separates the resources required by the vCenter and other management components from the resources required by the applications hosted in the virtual infrastructure.
While a separate management cluster can be beneficial for capacity planning, it can increases the costs associated with building a vSphere environment. A separate management cluster is not required, but it may be a good idea if you need to separate management components from other workloads.
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