VMware 4817V62 - vSphere - PC Instruction Manual

vSphere Basic System Administration
vCenter Server 4.0
ESX 4.0
ESXi 4.0
This document supports the version of each product listed and
supports all subsequent versions until the document is replaced
by a new edition. To check for more recent editions of this
document, see http://www.vmware.com/support/pubs.
EN-000105-08

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2 VMware, Inc.
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Contents
Updated Information 9
About This Book 11
Getting Started
1vSphere Components 15
Components of vSphere 15
vSphere Client Interfaces 17
Functional Components 17
Managed Components 19
Access Privileges Components 21
vCenter Server Modules 21
vCenter Components That Require Tomcat 22
Optional vCenter Server Components 22
2Starting and Stopping the vSphere Components 25
Start an ESX/ESXi Host 25
Reboot or Shut Down an ESX/ESXi Host 25
Stop an ESX Host Manually 26
Starting vCenter Server 26
Start the vSphere Client and Log In 27
Stop the vSphere Client and Log Out 28
vSphere Web Access 28
VMware Service Console 29
3Using vCenter Server in Linked Mode 31
Linked Mode Prerequisites 31
Linked Mode Considerations 32
Join a Linked Mode Group After Installation 32
Reconciling Roles When Connecting vCenter Server to a Linked Mode Group 33
Isolate a vCenter Server Instance from a Linked Mode Group 34
Change the Domain of a vCenter Server System in a Linked Mode Group 34
Configure the URLs on a Linked Mode vCenter Server System 34
Linked Mode Troubleshooting 35
Monitor vCenter Server Services 37
4Using the vSphere Client 39
Getting Started Tabs 40
Status Bar, Recent Tasks, and Triggered Alarms 40
Panel Sections 40
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View Virtual Machine Console 41
Searching the vSphere Inventory 41
Using Lists 42
Custom Attributes 43
Select Objects 44
Manage vCenter Server Plug-Ins 45
Save vSphere Client Data 46
5Configuring Hosts and vCenter Server 47
Host Configuration 47
Configuring vCenter Server 48
Access the vCenter Server Settings 48
Configuring Communication Among ESX, vCenter Server, and the vSphere Client 49
Configure vCenter Server SMTP Mail Settings 49
Working with Active Sessions 49
SNMP and vSphere 50
System Log Files 65
6Managing the vSphere Client Inventory 71
Understanding vSphere Client Objects 71
Add an Inventory Object 73
Moving Objects in the Inventory 74
Remove an Inventory Object 74
Browsing Datastores in the vSphere Client Inventory 75
7Managing Hosts in vCenter Server 77
About Hosts 77
Add a Host 78
Completing the Add Host Process 79
Disconnecting and Reconnecting a Host 80
Remove a Host from a Cluster 81
Understanding Managed Host Removal 81
Remove a Managed Host from vCenter Server 82
Monitoring Host Health Status 83
Virtual Machine Management
8Consolidating the Datacenter 87
Consolidation First Time Use 88
Consolidation Prerequisites 88
About Consolidation Services 91
Configuring Consolidation Settings 91
Find and Analyze Physical Systems 92
Viewing Analysis Results 93
Converting Physical Systems to Virtual Machines 93
Viewing Consolidation Tasks 94
Troubleshooting Consolidation 95
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9Deploying OVF Templates 99
About OVF 99
Deploy an OVF Template 99
Browse VMware Virtual Appliance Marketplace 101
Export an OVF Template 101
10 Managing VMware vApp 103
Create a vApp 103
Populate the vApp 105
Edit vApp Settings 106
Configuring IP Pools 109
Clone a vApp 111
Power On a vApp 111
Power Off a vApp 112
Edit vApp Annotation 112
11 Creating Virtual Machines 113
Access the New Virtual Machine Wizard 113
Select a Path Through the New Virtual Machine Wizard 114
Enter a Name and Location 114
Select a Resource Pool 114
Select a Datastore 115
Select a Virtual Machine Version 115
Select an Operating System 115
Select the Number of Virtual Processors 115
Configure Virtual Memory 116
Configure Networks 116
About VMware Paravirtual SCSI Adapters 116
Select a SCSI Adapter 117
Selecting a Virtual Disk Type 117
Complete Virtual Machine Creation 120
Installing a Guest Operating System 120
Installing and Upgrading VMware Tools 120
12 Managing Virtual Machines 133
Changing Virtual Machine Power States 134
Adding and Removing Virtual Machines 137
Configure Virtual Machine Startup and Shutdown Behavior 138
13 Virtual Machine Configuration 141
Virtual Machine Hardware Versions 141
Virtual Machine Properties Editor 142
Adding New Hardware 156
Converting Virtual Disks from Thin to Thick 163
14 Working with Templates and Clones 165
Creating Templates 165
Contents
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Edit a Template 167
Change Template Name 168
Deploy Virtual Machines from Templates 168
Convert Templates to Virtual Machines 169
Deleting Templates 169
Regain Templates 170
Clone Virtual Machines 170
Create a Scheduled Task to Clone a Virtual Machine 171
15 Customizing Guest Operating Systems 173
Preparing for Guest Customization 173
Customize Windows During Cloning or Deployment 175
Customize Linux During Cloning or Deployment 176
Create a Customization Specification for Linux 177
Create a Customization Specification for Windows 177
Managing Customization Specification 179
Completing a Guest Operating System Customization 180
16 Migrating Virtual Machines 183
Cold Migration 184
Migrating a Suspended Virtual Machine 184
Migration with VMotion 184
Migration with Storage VMotion 193
Migrate a Powered-Off or Suspended Virtual Machine 194
Migrate a Powered-On Virtual Machine with VMotion 195
Migrate a Virtual Machine with Storage VMotion 196
Storage VMotion Command-Line Syntax 198
17 Using Snapshots 201
About Snapshots 201
Using the Snapshot Manager 204
Restore a Snapshot 205
System Administration
18 Managing Users, Groups, Roles, and Permissions 209
Managing vSphere Users 209
Groups 210
Removing or Modifying Users and Groups 211
Best Practices for Users and Groups 211
Using Roles to Assign Privileges 211
Permissions 215
Best Practices for Roles and Permissions 222
Required Privileges for Common Tasks 223
19 Monitoring Storage Resources 225
Working with Storage Reports 225
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Working with Storage Maps 227
20 Using vCenter Maps 229
vCenter VMotion Maps 230
vCenter Map Icons and Interface Controls 230
View vCenter Maps 231
Print vCenter Maps 231
Export vCenter Maps 231
21 Working with Alarms 233
Alarm Triggers 234
Alarm Actions 243
Alarm Reporting 248
Creating Alarms 248
Managing Alarms 252
Managing Alarm Actions 256
Preconfigured VMware Alarms 259
22 Working with Performance Statistics 261
Statistics Collection for vCenter Server 261
vCenter Server Performance Charts 268
Monitoring and Troubleshooting Performance 273
23 Working with Tasks and Events 279
Managing Tasks 279
Managing Events 285
Appendixes
ADefined Privileges 291
Alarms 292
Datacenter 293
Datastore 293
Distributed Virtual Port Group 294
Distributed Virtual Switch 295
Extensions 296
Folders 296
Global 297
Host CIM 298
Host Configuration 298
Host Inventory 300
Host Local Operations 301
Host Profile 302
Network 302
Performance 303
Permissions 304
Resource 304
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Scheduled Task 306
Sessions 306
Tasks 307
vApp 307
Virtual Machine Configuration 309
Virtual Machine Interaction 313
Virtual Machine Inventory 316
Virtual Machine Provisioning 317
Virtual Machine State 320
BInstalling the Microsoft Sysprep Tools 321
Install the Microsoft System Preparation Tools from a Microsoft Web Site Download 321
Install the Microsoft Sysprep Tools from the Windows Operating System CD 322
CPerformance Metrics 325
Cluster Services Metrics 326
CPU Metrics 327
Disk Metrics 331
Management Agent Metrics 335
Memory Metrics 336
Network Metrics 344
Storage Utilization Metrics 346
System Metrics 347
Virtual Machine Operations Metrics 348
Index 351
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Updated Information
This Basic System Administration is updated with each release of the product or when necessary.
This table provides the update history of the Basic System Administration.
Revision Description
EN-000105-08 Changed a point in “Configuring Communication Among ESX, vCenter Server, and the vSphere Client,”
on page 49 section.
EN-000105-07 nThe topics “Windows Requirements for Guest Customization,” on page 174 and “Linux Requirements
for Guest Customization,” on page 175 now have reference to the vSphere Compatibility Matrixes
document for information on the list of operating system that are supported for guest OS cutomization.
nThe topic “About Snapshots,” on page 201 now reflects that VMware does not support snapshots of
virtual machines configured with bus-sharing.
nIn “Disk Metrics,” on page 331, corrected the table. The latency counters were marked as available for
V (virtual machines) and H (hosts), when they are actually only available for hosts.
nIn “Memory Metrics,” on page 336, corrected the table. The sharedcommon counter was marked as
available for V (virtual machines) and H (hosts), when it is actually only available for hosts.
EN-000105-06 nIn certain topics, removed references to Microsoft Outlook Express.
nIn “Upgrade VMware Tools Manually,” on page 128, updated Step 5to show that you do not have to
power-off the virtual machines when upgrading VMware Tools manually.
EN-000105-05 nIn “Specify an IP Address Range,” on page 109, updated the incorrect IPv4 address from 10.209.60.13
to 10.20.60.13.
nIn Chapter 17, “Using Snapshots,” on page 201, added information that you can use snapshot as a
restoration point during a linear or iterative process.
nIn “About Snapshots,” on page 201, added a link to a KB article.
nIn “Revert to Snapshot Command,” on page 205, added information about taking the snapshot when
the virtual machine is powered off.
nIn “Collection Intervals,” on page 263, updated that ESXi retains real-time statistics for one hour instead
of 30 minutes.
nIn “Disk Metrics,” on page 331, updated the Stats Type as rate and Unit as kiloBytesPerSecond in the
usage counter of the Table C-3.
EN-000105-04 nIn “Edit vApp Startup and Shutdown Options,” on page 106 the tab name is changed from Start up to
Start Order.
nA note added to “View vApp License Agreement,” on page 107 clarifies the condition required to view
the vApp license agreement.
nThe alarms Virtual Machine CPU Ready, Virtual machine disk commands canceled, and Virtual
machine disk reset are removed from the Default VMware Alarms table in “Preconfigured VMware
Alarms,” on page 259.
n“How Metrics Are Stored in the vCenter Server Database,” on page 267 now reflects that the maximum
number of years for which the vCenter Server Database can store statistical data is 5 years.
EN-000105-03 nThe list of supported guest operating systems in topic “Linux Requirements for Guest
Customization,” on page 175 has been revised.
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Revision Description
EN-000105-02 nThe following sentence has been removed from the note in“Change the Virtual Processor or CPU
Configuration,” on page 148: "Changing the number of processors an imported virtual machine uses
is not supported." This information no longer pertains to vSphere.
nAdded information to “About Snapshots,” on page 201 that clarifies the issue of using snapshots for
virtual machine backups.
EN-000105-01 nThe topic “Add a USB Controller to a Virtual Machine,” on page 163 now reflects that although you
can add a USB controller to a virtual machine, adding USB devices is not supported.
nChapter 16, “Migrating Virtual Machines,” on page 183 has been revised to remove references to
VMware Server. VMware Server hosts are not supported by vCenter Server.
nIn Table A-22 the description for the Host USB device privilege now reflects that adding USB devices
to virtual machines is not supported.
nMinor revisions.
EN-000105-00 Initial release.
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About This Book
This manual, Basic System Administration, describes how to start and stop the VMware® vSphere™ Client
components, build your vSphere environment, monitor and manage the information generated about the
components, and set up roles and permissions for users and groups using the vSphere environment. This
manual also provides information for managing, creating, and configuring virtual machines in your datacenter.
In addition, this manual provides brief introductions to the various tasks you can perform within the system
as well as cross-references to the documentation that describes all the tasks in detail.
Basic System Administration covers ESX, ESXi, and vCenter Server.
Intended Audience
The information presented in this manual is written for system administrators who are experienced Windows
or Linux system administrators and who are familiar with virtual machine technology and datacenter
operations.
Document Feedback
VMware welcomes your suggestions for improving our documentation. If you have comments, send your
feedback to [email protected].
VMware vSphere Documentation
The vSphere documentation consists of the combined VMware vCenter Server and ESX/ESXi documentation
set.
Abbreviations Used in Figures
The figures in this manual use the abbreviations listed in Table 1.
Table 1. Abbreviations
Abbreviation Description
database vCenter Server database
datastore Storage for the managed host
dsk# Storage disk for the managed host
hostn vCenter Server managed hosts
SAN Storage area network type datastore shared between
managed hosts
tmplt Template
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Table 1. Abbreviations (Continued)
Abbreviation Description
user# User with access permissions
VC vCenter Server
VM# Virtual machines on a managed host
Technical Support and Education Resources
The following technical support resources are available to you. To access the current version of this book and
other books, go to http://www.vmware.com/support/pubs.
Online and Telephone
Support
To use online support to submit technical support requests, view your product
and contract information, and register your products, go to
http://www.vmware.com/support.
Customers with appropriate support contracts should use telephone support
for priority 1 issues. Go to
http://www.vmware.com/support/phone_support.html.
Support Offerings To find out how VMware support offerings can help meet your business needs,
go to http://www.vmware.com/support/services.
VMware Professional
Services
VMware Education Services courses offer extensive hands-on labs, case study
examples, and course materials designed to be used as on-the-job reference
tools. Courses are available onsite, in the classroom, and live online. For onsite
pilot programs and implementation best practices, VMware Consulting
Services provides offerings to help you assess, plan, build, and manage your
virtual environment. To access information about education classes,
certification programs, and consulting services, go to
http://www.vmware.com/services.
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Getting Started
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vSphere Components 1
VMware vSphere™ includes components and operations essential for managing virtual machines. vSphere
works with several client interfaces and offers many optional components and modules, such as VMware High
Availability (HA), VMware VMotion™, VMware Distributed Resource Scheduler (DRS), VMware Update
Manager, and VMware Converter Enterprise.
vSphere allows you to treat your virtual environment objects as managed components such as virtual machines,
hosts, datacenters, resource pools, and clusters. Functional components of vSphere provide the best way to
manage each of these managed components of your virtual environment.
Finally, vSphere provides powerful administration tools through access privileges components.
This chapter includes the following topics:
n“Components of vSphere,” on page 15
n“vSphere Client Interfaces,” on page 17
n“Functional Components,” on page 17
n“Managed Components,” on page 19
n“Access Privileges Components,” on page 21
n“vCenter Server Modules,” on page 21
n“vCenter Components That Require Tomcat,” on page 22
n“Optional vCenter Server Components,” on page 22
Components of vSphere
VMware vSphere is a suite of software components for virtualization.
To run your vSphere environment, you need the following components:
ESX/ESXi A virtualization platform used to create the virtual machines as a set of
configuration and disk files that together perform all the functions of a physical
machine.
Through ESX/ESXi, you run the virtual machines, install operating systems,
run applications, and configure the virtual machines. Configuration includes
identifying the virtual machine’s resources, such as storage devices.
The server provides bootstrapping, management, and other services that
manage your virtual machines.
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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.
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Host agent On each managed host, software that collects, communicates, and executes the
actions received through the vSphere Client. It is installed as part of the
ESX/ESXi installation.
LDAP vCenter Server uses LDAP (Lightweight Directory Access Protocol) to
synchronize data such as license and role information across vCenter Server
systems joined in Linked Mode.
vSphere Client Interfaces
There are several ways to access vSphere components.
vSphere interface options include:
vSphere Client A required component and the primary interface for creating, managing, and
monitoring virtual machines, their resources, and their hosts. It also provides
console access to virtual machines.
vSphere Client is installed on a Windows machine with network access to your
ESX/ESXi or vCenter Server system installation. The interface displays slightly
different options depending on which type of server you are connected to.
While all vCenter Server activities are performed by a vCenter Server system,
you must use the vSphere Client to monitor, manage, and control the server.
A single vCenter Server system or ESX/ESXi host can support multiple,
simultaneously connected vSphere Clients.
vSphere Web Access A Web interface through which you can perform basic virtual machine
management and configuration and get console access to virtual machines. It
is installed with your ESX/ESXi host. Similar to the vSphere Client, vSphere
Web Access works directly with a host or through vCenter Server. See the
vSphere Web Access Administrator’s Guide for additional information.
VMware Service Console A command-line interface for configuring an ESX host. For an ESXi host, use
the vSphere Command-Line Interface.
vSphere Command-Line
Interface
A command-line interface for configuring an ESXi host. The vSphere
Command-Line Interface can also be used to perform Storage VMotion
operations on both ESX/ESXi hosts.
Functional Components
Functional components are used to monitor and manage your vSphere infrastructure.
The functional components are accessible from the vSphere Client Home page. Functional components are
divided into four categories: Inventory, Administration, Management, and Solutions and Applications.
Inventory
You use the Inventory functional components to view the objects managed by vCenter Server. Managed objects
include datacenters, resource pools, clusters, networks, datastores, templates, hosts, and virtual machines. The
inventory options are:
Search Allows you to search the vSphere inventory for hosts, virtual machines,
networks, datastores, and folders matching specified criteria.
Hosts and Clusters Provides a hierarchical view of hosts, clusters, and their child objects.
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VMs and Templates Provides a view of all virtual machines and templates in the inventory, grouped
by datacenters and folders.
Datastores Provides a view of all datastores in the inventory, grouped by datacenters and
folders.
Networks Provides a view of all networks in the inventory, grouped by datacenters and
folders.
Administration
You use the Administration functional components to configure and monitor the state of your hosts or vCenter
Server systems. The options are:
Roles Allows you to view and create roles used to grant access privileges to users.
Sessions Allows you to view all vSphere Client sessions currently connected to the
selected vCenter Server system. If you have sufficient privileges, you can
terminate sessions. Sessions are available through vCenter Server only.
Licensing Allows you to view and administer vSphere licenses. This is available through
vCenter Server only. To administer licenses for a standalone host, use the host
Configuration tab.
System Logs Allows you to display and export log files.
vCenter Server Settings Allows you to configure a number of settings for the selected vCenter Server
system. The vCenter Server settings are available through vCenter Server only.
vCenter Server Status Provides a list of vSphere services with their current status. The status details
include warning and alert information.
Guided Consolidation Analyzes computers in your enterprise and recommends the best candidates
to virtualize. The consolidation interface guides you through the conversion
process based on the computers you select for consolidation.
Management
You use the Management functional components to monitor and manage the objects in the vSphere inventory.
Management functional components are available through vCenter Server only. The options are:
Scheduled Tasks Provides a list of activities and a means to schedule those activities. Scheduled
tasks are available through vCenter Server only.
Events Provides a list of all the events that occur in the vCenter Server environment.
Use this option to view all events. To see only events relevant to a particular
object, use the Tasks & Events tab for that object. Events are available through
vCenter Server only.
Maps Provides a visual representation of the status and structure of the vSphere
environment and the relationships between managed objects. This includes
hosts, networks, virtual machines, and datastores. Maps are available only
through vCenter Server.
Host Profiles Allows you to view, create, apply, and check compliance for host profiles.
Customization
Specifications Manager
Allows you to create new virtual machine guest operating system
specifications and manage existing specifications.
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Solutions and Applications
You use the Solutions and Applications panel to access vCenter Server extensions installed in your vCenter
Server System. For example, you can access the VMware vCenter Guided Consolidation extension and the
VMware vCenter Update Manager from this panel.
NOTE This panel appears only if you purchased and installed VMware vSphere extensions that are sold
separately from the VMware vCenter Server product.
Managed Components
Managed components are objects in your virtual and physical infrastructure on which you can place
permissions, monitor tasks and events, and set alarms. You can group most managed components by using
folders to more easily manage them.
All managed components, with the exception of hosts, can be renamed to represent their purposes. For
example, they can be named after company departments or locations or functions. vCenter Server monitors
and manages the following components of your virtual and physical infrastructure:
Clusters A collection of ESX/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. The cluster manages the resources of all
hosts.
If you enable VMware 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
VMware HA on a cluster, the resources of the cluster are managed as a pool of
capacity to allow rapid recovery from host hardware failures.See the Resource
Management Guide.
Datacenters Unlike a folder, which is used to organize a specific object type, a datacenter is
an aggregation of all the different types of objects needed to do work in virtual
infrastructure: hosts, virtual machines, networks, and datastores.
Within a datacenter there are four separate hierarchies.
nVirtual machines (and templates)
nHosts (and clusters)
nNetworks
nDatastores
The datacenter is the unit of virtualization (the namespace) of networks and
datastores. Within a datacenter, you cannot have two objects (for example, two
hosts) with the same name but you can have two objects with the same name
in different datacenters. Virtual machine names need not be unique within the
datacenter, but must be unique within each virtual machine folder.
If two virtual machines connect to networkA, they are connected to the same
network. Rules are different across datacenters. Theoretically, the same
physical network can appear in two datacenters and be called two different
names. Or networkA might have one meaning in datacenterA and a different
meaning in datacenterB. Moving objects between datacenters can create
problems or, at least, unpredictable results.
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To have a single namespace (that is, a single datacenter) for all networks and
datastores, use folders within the datacenter to organize the networks and
datastores. To have separate namespaces (separate datacenters) for networks
and datastores, create two datacenters.
Datastores 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.
Folders A top-level structure for vCenter Server only. 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:
datacenters, 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.
The datacenter folders form a hierarchy directly under the root vCenter Server
and allow users to group their datacenters in any convenient way. Within each
datacenter is one hierarchy of folders with virtual machines and templates, one
with hosts and clusters, one with datastores, and one with networks.
Hosts The physical computer on which the virtualization platform software, such as
ESX/ESXi, is installed and all virtual machines reside. If the vSphere Client is
connected directly to an ESX/ESXi host, only that host is available for
management.
NOTE When vCenter Server refers to a host, this means the physical machine
on which the virtual machines are running. All virtual machines within the
VMware vSphere environment are physically on ESX/ESXi hosts. The term host
in this Help system refers to the ESX/ESXi host that has virtual machines on it.
Networks A set of virtual network interface cards (virtual NIC), virtual switches
(vSwitch), and port groups that connect virtual machines to each other or to
the physical network outside of the virtual datacenter. All virtual machines that
connect to the same port group belong to the same network in the virtual
environment, even if they are on different physical servers. You can monitor
networks and set permissions and alarms on port groups.
Resource pools A structure that allows delegation of control over the resources of a host.
Resource pools are used to compartmentalize all resources in a cluster. You can
create multiple resource pools as direct children of a host or cluster and
configure them. Then delegate control over them to other individuals or
organizations. The managed resources are CPU and memory from a host or
cluster. Virtual machines execute in, and draw their resources from, resource
pools.
vCenter Server provides, through the DRS components, various options in
monitoring the status of the resources and adjusting or suggesting adjustments
to the virtual machines using the resources. You can monitor resources and set
alarms on them.
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