6.7

The data center defines the namespace for networks and datastores. The
names for these objects must be unique within a data center. You cannot
have two datastores with the same name within a single data center, but
you can have two datastores with the same name in two different data
centers. Virtual machines, templates, and clusters need not be unique
within the data center, but must be unique within their folder.
Objects with the same name in two different data centers are not
necessarily the same object. Because of this, moving objects between data
centers can create unpredictable results. For example, a network named
networkA in data_centerA might not be the same network as a network
named networkA in data_centerB. Moving a virtual machine connected to
networkA from data_centerA to data_centerB results in the virtual machine
changing the network it is connected to.
Clusters A collection of ESXi hosts and associated virtual machines intended to
work together as a unit. When you add a host to a cluster, the host’s
resources become part of the cluster’s resources. vCenter Server manages
the resources of all hosts in a cluster as one unit.
If you enable VMware EVC on a cluster, you can ensure that migrations
with vMotion do not fail because of CPU compatibility errors. If you enable
vSphere DRS on a cluster, the resources of the hosts in the cluster are
merged to allow resource balancing for the hosts in the cluster. If you
enable vSphere HA on a cluster, the resources of the cluster are managed
as a pool of capacity to allow rapid recovery from host hardware failures.
Datastores A virtual representation of physical storage resources in the data center. A
datastore is the storage location for virtual machine files. In an on-premises
SDDC, these physical storage resources can come from the local SCSI
disk of the ESXi host, the Fibre Channel SAN disk arrays, the iSCSI SAN
disk arrays, or Network Attached Storage (NAS) arrays. For both on-
premises and cloud SDDCs, vSAN datastores hide the idiosyncrasies of
the underlying physical storage and present a uniform model for the
storage resources required by virtual machines.
Folders Folders allow you to group objects of the same type so you can easily
manage them. For example, you can use folders to set permissions across
objects, to set alarms across objects, and to organize objects in a
meaningful way.
A folder can contain other folders, or a group of objects of the same type:
data centers, clusters, datastores, networks, virtual machines, templates, or
hosts. For example, one folder can contain hosts and a folder containing
hosts, but it cannot contain hosts and a folder containing virtual machines.
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