Installation guide

Each ESX/ESXi host has a vSphere Client available for your management use.
If your ESX/ESXi host is registered with vCenter Server, a vSphere Client that
accommodates vCenter Server features is available.
vCenter Server
A service that acts as a central administrator for VMware ESX/ESXi hosts that
are connected on a network. vCenter Server directs actions on the virtual
machines and the virtual machine hosts (the ESX/ESXi hosts).
vCenter Server is a single Windows Service and is installed to run
automatically. vCenter Server runs continuously in the background,
performing its monitoring and managing activities even when no vSphere
Clients are connected and even if nobody is logged on to the computer where
it resides. It must have network access to all the hosts it manages and be
available for network access from any machine where the vSphere Client is run.
vCenter Server can be installed in a Windows virtual machine on an ESX/ESXi
host, allowing it to take advantage of the high-availability afforded by VMware
HA. See the Installation Guide for details on setting up this configuration.
Multiple vCenter Server systems can be joined together using Linked Mode to
allow them to be managed using a single vSphere Client connection.
vCenter Server plug-ins
Applications that provide additional features and functionality to vCenter
Server. Typically, plug-ins consist of a server component and a client
component. After the plug-in server is installed, it is registered with vCenter
Server and the plug-in client is available to vSphere clients for download. After
a plug-in is installed on a vSphere client, it might alter the interface by adding
views, tabs, toolbar buttons, or menu options related to the added functionality.
Plug-ins leverage core vCenter Server capabilities, such as authentication and
permission management, but can have their own types of events, tasks,
metadata, and privileges.
In addition to plug-ins that are available independently of vCenter Server,
some vCenter Server features are implemented as plug-ins, and can be
managed using the vSphere Client Plug-in Manager. These features include
vCenter Storage Monitoring, vCenter Hardware Status, and vCenter Service
Status.
vCenter Server database
A persistent storage area for maintaining status of each virtual machine, host,
and user managed in the vCenter Server environment. The vCenter Server
database can be remote or local to the vCenter Server system.
The database is installed and configured during vCenter Server installation.
If you are accessing your ESX/ESXi host directly through a vSphere Client, and
not through a vCenter Server system and associated vSphere Client, you do
not use a vCenter Server database.
Datastore
A virtual representation of combinations of underlying physical storage
resources in the datacenter. A datastore is the storage location for virtual
machine files. These physical storage resources can come from the local SCSI
disk of the server, the Fibre Channel SAN disk arrays, the iSCSI SAN disk
arrays, or Network Attached Storage (NAS) arrays. Datastores hide the
idiosyncrasies of the storage options and provide a uniform model for various
storage products required by virtual machines.
vCenter Server agent
On each managed host, software that collects, communicates, and executes the
actions received from vCenter Server. The vCenter Server agent is installed the
first time any host is added to the vCenter Server inventory.
vSphere Basic System Administration
16 VMware, Inc.