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VMware Notes

ESX/ESXi Log files



Contain entries made during bootup and while the system is running

ESX also has


log files

Track service console availability, VMkernel alerts, warning,
messages and ESX host

Remote command prompt management

vSphere Command Line Interface

) application

VMware vSphere Management Assistant

(vMA) virtual appliance


A platform for running a variety of toolkits such as vCLI, vSphere SD
K for Perl and
vSphere API

VMware vSphere PowerCLI


Automation tool for administering a vSphere environment


Distributed as a snap in to Windows Power Shell

vCenter Server Maximums

1,000 hosts

10,000 powered on VMs

15,000 registered VMs

vCenter S

Core Services

management of resources and VMs, task scheduling, statistics logging,

management of alarms and events, VM provisioning and host and VM configuration

Distributed Services

vMotion, DRS and HA

vCenter Hardware

and Software



64 bit CPUs or one 64 bit dual core processor (
2.0 GHz

or higher)


RAM minimum

disk storage minimum

Gigabit network recommended

64 bit OS

XP Pro 64 bit SP2, 2003 Enterprise SP2, 2008 R2 64 bit

vCenter Supported Databases

SQL 2005 and 2008


10g and 11g

IBM DB2 9.5

SQL 2005 Express

vCenter Ports






UDP heartbeat


Web Services HTTP


Web Services HTTPS


Web services change service notification





Java Virtual Machine (


VMware VirtualCenter

Requires 1
4GB of additional memory

1GB for less than 100 hosts

4GB for more than 400 hosts

vCenter Windows Services

VMware Mount Service for Virtual Center

Used during guest OS customization

cloning or deploying from a template.

VMware vCenter Orchestrator Configuration

Used for Orchestrator which is a
workflow engine that helps admins automate existing manual tasks.

VMware VirtualCenter Management Webservices

Allows configuration

of vCenter
management services.

VMware VirtualCenter Server


Provides vCenter Server LDAP directory services.

vCenter Plugins

vCenter Storage Monitoring

Allows vCenter Server to monitor and report on


and adds the
Storage Views

tab to the vSphere client

vCenter Service Status

(health status)

adds the vCenter Service Status icon to the

Administration panel in the vSphere client

vCenter Hardware Status

Allows vCenter to display the hardware status of the


and adds the
Hardware Status tab to the vSphere client.

vCenter Server uses the root account to add hosts to the inventory and creates a special user
account named

for all future authentication

Lockdown Mode

(ESXi only)

Disables remote access for the admin
istrator account to ensure
host is only managed by vCenter

You can add ESX 2.5.x and later as well as ESXi 3.5 and later

hosts to the vCenter Inventory

VPXA Process

vCenter Server agent that pr
ovides access to ESX/ESXi hosts

Resides on ESX/ESXI

Installed when the host is added to vCenter


process communicates with the host agent known
as the

process to relay

the tasks to perform on the host


ot used if logged in directly to the host but instead communications use hostd


vCenter can also manage licenses for legacy hosts such as ESX 3.x and ESX

3.5 using a separate
license server.

You can’t have 2 Virtual switches (Layer 2 devices) mapped to the same physical NIC.

You can have 2 or more physical NICs mapped to the

same virtual switch.

Standard virtual switch

Maximum of

virtual switch ports per switch

Maximum of

virtual switch ports per host


switch ports created by default

Virtual switch ports used for VM connections and for uplinks to physical NICs

Some ports used for internal purposes by the VMkernel


Can be configured at the port group level

ESX/ESXi host
s provide

VLAN support through virtual switch tagging (gives a port group


VMkernel then takes care of all the tagging

A switch p
ort on the physical host must be define

as a static trunk port

No VLAN configuration is needed on the VM

Network Policies

Security, Traffic shaping and NIC teaming

Defined at the standard virtual switch level for the entire switch

Can also be defined for

a VMkernel port, VM port group and ESX service console

Policies defined for an individ
ual port or port group override

the default policies defined
for the switch.

Network security policy exceptions

Promiscuous Mode

when set to reject, placing a gu
est adapter in promiscuous mode
has no effect on which frames are received by the adapter (default is


Promiscuous mode


if you want to use an application in a VM that
analyzes of sniffs packets.

MAC Address Change

When set to Reject, if the guest attempts to change the MAC
address assigned to the virtual NIC, it stops receiving the frames. (default is

Forged Transmits

When set to Reject, the virtual NIC drops any frames that the guest

sends, where the s
ource address field contains a MAC address other than the assigned
virtual NIC MAC address (default is

MAC Address Changes

Forged Transmits


to help protect against
certain attacks launched by a rouge guest operating system.

MAC Address Changes

Forged Transmits

at their default values of

you applications change the mapped MAC address.

Traffic shaping shapes outbound network traffic only when used on a stand
ard virtual switch

Off by default

ESX/ESXi hosts shape outbound traffic only by establishing parameters for 3 traffic
Average Bandwidth
Peak Bandwidth

Burst Size

Establish the policy at the virtual switch level or the port group level

Settings at the port group level

override the settings at the switch level

Average Bandwidth

Establishes the number of

per second to allow across a port, averaged over

The average bandwidth is the allowed average load.

Peak Bandwidth

The maximum number of

per sec
ond to allow across a port when it is sending a
burst of traffic.

This tops the bandwidth used by a port whenever the ports is using it burst bonus.

Burst Size

The maximum number of

to allow in a burst.

If this parameter is set, a port might gain

a burst bonus if it does not use all its allocated

NIC Teaming

Policies include load balancing and failover settings

Default policies are set for the entire Standard Switch

Policies can be overridden at the port group level

Virtual Port ID
load balancing

a VMs outbound traffic is mapped to a specific physical
NIC. This method is simple and fast and does not require the VMkernel to examine the
frame for necessary information.

MAC Hash load balancing

Each VMs outbound traffic is mapped to
a specific physical
NIC’s MAC address. This method has low overhead and is compatible with all switches
but may not spread traffic evenly across physical NICs.

IP Hash load balancing

A NIC for each outbound packet is chosen based on its source
and destin
ation IP address. This method has higher CPU overhead but a better
distribution of traffic across physical NICs.

It also requires 802.3ad link aggregation
support or EtherChannel on the switch.

Network failure is detected by the VMkernel, which monitors:

Link state only

Detects cable pulls and physical switch failures. Doesn’t detect
configuration errors.


state plus beaconing

VMkernel sends out and listens for probe packets on all
NICs in the team

Switches can be notified whenever:

There is a fail
over event

A new virtual NIC is connected to the virtual switch

Failover implemented by the VMkernel based on configurable parameters:


Determines how a physical adapter is returned to active duty after recovering
from a failure
. If set to Yes, t
he failed adapter is returned to active duty immediately
after recovery, displacing the standby adapter that took its place. If set to No, the failed
adapter is left inactive after recovery until needed.


balancing option: Use explicit failover order

Always use the highest order uplink
from the list of active adapters that pass failover detection criteria.


A clustered file system that allows multiple physical servers to read and write to the
same storage simultaneously.

A VMFS datastore can be
configured to use an 8MB block size to support virtual disk
files up to 2TB.

A VMFS datastore uses subblock addressing to make efficient use of storage for small


File sharing protocol used to communicate with a NAS device

NFS datastores are tre
ated like VMFS datastores

can hold VM files, ISOs, templates
and use vMotion etc.

ESX/ESXi supports NFS version 3 over TCP only

ESX/ESXi hosts do not use the standard Network Lock Manager (NLM) protocol

VMware uses its own locking protocol. NFS locks are

implemented by creating lock files
on the NFS server. Lock files are named

where <fileID> is the value of the
fileID field. The lock file generates small 84
byte WRITE requests to the NFS server.


Raw Device Mapping

Acts as a proxy
for a raw physical device

Stores data directly on a raw LUN

Can be used for data, VM clustering and storage array snapshots

Allows you to use your existing SAN commands to manage storage for the disk

Used when clustering VMs using Microsoft Clustering Serv
ice (MSCS)

A VMFS datastore can be used to hold RDMs that point to raw iSCSI volumes.

Thin provisioning disks can reduce the cost of storage for virtual environments by up to 50%.

SCSI Storage Devices


The unique address of a SCSI device

Canonical name

The Network Address Authority ID. Globally unique identifiers that

are persistent across system reboots.

The T10 identifier is another unique identifier. It can appear on any SCSI device.

They always begin with the string


is a VMw
are namespace that is used when no other valid namespaces can
be obtained from the LUN. It is not globally unique or persistent across reboots.


name is the name of the first path to the device. It is created by the host. It is
not reliable or persi

ESX/ESXi support 2 types of IP storage


Used to hold one or more VMFS datastores


Used to hold one or more NFS datastores

Both support vSphere features like vMotion, HA and DRS

ESX/ESXi supports:

Up to 64 NFS volumes

iSCSI or NFS over
a 10GbE interface

iSCSI or NFS in an IPv6 environment (experimental only)

ESX/ESXi supports booting from an iSCSI SAN

ESX hosts: From

hardware iSCSI

ESXi hosts: From software iSCSI and

hardware iSCSI

The network adapter
must support

only the iSCSI Boot Firmware Table (iBFT) format.

The ESX/ESXi host is configured with a software or hardware iSCSI initiator

Hardware is an iSCSI HBA

Software is an iSCSI Initiator

Software initiator is VMware code built into the VMkernel.

Hardware init
iator is a 3

party adapter capable of accessing iSCSI storage over TCP/IP

The Dependent hardware initiator depends on VMware networking and on iSCSI
configuration and management interfaces provided by VMware. You need to bind the
adapter and an appropria
te VMkernel iSCSI port.

An independent hardware adapter handles all the iSCSI and network processing and
management for the ESX/ESXi host.

LUN Masking is available for iSCSI and works the same as in Fibre Channel.

Ethernet switches don’t use Zones like F
C but rather use VLANs instead.

iSCSI Names

iSCSI qualified name (IQN) or the Extended Unique Identifier (EUI)



iSCSI qualified name

Can be up to 255 characters long

Uses the prefix

Has a date code specifying the year and month in which the
organization registered the
domain or subdomain uses as the naming authority string

Has an organizational naming authority string which consists of a valid, reversed domain
or subdomain name

May have a colon (:) followed by a string of the assigning organi
zation’s choosing





Extended Unique Identifier

Uses the prefix

followed by a 16 character name. The name includes 24 bits for a
company name that is assigned by th
e IEEE and 40 bits for a unique ID, such as a serial



Configuring a iSCSI software initiator

Create a VMkernel port

on a virtual switch

Enable the software iSCSI initiator

Configure one or more target discovery
addresses so that the iSCSI initiator can
determine which storage resources on the network is available for access. You cannot
change the IP address, iSCSI name, or port number of an existing target. To make
changes, remove the target and make a new one

nfigure Challenge Handshake

Protocol (CHAP)

if needed.

ESX/ESXi supports per
target CHAP where you use different credentials for each target
(Software iSCSI only)

ESX/ESXi supports two iSCSI target discovery methods

Static Discovery

The initiator does not need to perform discovery. It knows in advance
all the targets it will be contacting and uses their IP addresses and domain names to
communicate with them.

Dynamic Discovery (SendTargets discovery)

Each time the initiator contacts

specified iSCSI server; it sends the SendTargets request to the server. The server
responds by supplying a list of available targets to the initiator. The names and IP
addresses of these targets appear as static in the vSphere client.


Unidirectional (one way CHAP)

the target authenticates the initiator, but the initiator
does not authenticate the target. You specify the CHAP secret.

(Hardware and software

Bidirectional (mutual CHAP)

The initiator is able to authenticate the
target as well
(Software iSCSI only).

Only Unidirectional CHAP is available for hardware initiators

Configuring the iSCSI initiator

Install the iSCSI hardware adapter

Modify the iSCSI name and configure the iSCSI alias

Configure iSCSI target addresses

figure iSCSI security (CHAP)

NFS Privileges

NFS privileges are assigned to the root user


is on, the NFS server treats access by the root

user as access by any
unprivileged user and might refuse the ESX/ESXi host access to VM files stored
on the
NFS volume.

You must use the


option instead to export an NFS volume. It allows the
root user to be recognized as root.

The NFS administrator must allow read and write privileges to the NFS datastore with

you are depl
oying VMs on the NFS datastore.

Configuring an NFS Datastore

Separate it from the iSCSI network for better security and performance

Provide the NFS server name or IP address

Provide the folder on the NFS server

Choose whether to mount the NFS file system
only or not. Use read
only for ISO
libraries and read/write for VMs

Choose the NFS datastore name

To see NFS datastores go to the Storage Views tab and display the Show all NAS Mounts

To unmount an NFS datastore right click the datastore and select

or select the
datastore and click the


Fibre Channel

ESX/ESXi supports 8Gb Fibre Channel and Fibre Channel over Ethernet (FCoE)

You can boot ESX/ESXi from a Fibre Channel SAN LUN

The BIOS of the Fibre Channel
adapter must be configur
ed with the World Wide Name (WWN) and LUN number of the
boot device.

A Fibre Channel SAN consists of:

Storage System

Physical hard disks (array) and one or more intelligent controllers. The
storage system supports the creation of LUNs (logical volumes)


The address of a logical unit (LU). An LU can be a JBOD (Just a Bunch Of Disks)
, a
RAID set or part of a storage container

Storage Processor

A storage processor can partition a JBOD or RAID set into one or
more LUNs. Each connection is referenced b
y the HBA’s WWN.


Connects the ESX/ESXi host to the Fibre Channel network. A minimum of 2 HBA
adapters are used for FT

Fibre Channel Switches

One or more Fibre Channel switches form the Fibre Channel
fabric. The Fibre Channel fabric interconnects mu
ltiple nodes.

Soft Zoning

Controls LUN visibility per WWN and is done at the Fibre Channel switch

Hard Zoning

The control of storage processor visibility per switch port

Fabric Zoning

Controls target presentation and tells an ESX/ESXi host whether

a target exists

WWNs are assigned by the manufacturer of the SAN. HBAs and storage processors have WWNs.
They are used to identify equipment for zoning purposes.

LUN Masking

Controls LUN visibility per host. Can be done in the ESX/ESXi host or at the
storage processor level (more secure and better data integrity)

The VMkernel scans for LUNs 0
255 (256 total). You can’t have a LUN with an ID over 256.

Storage Views


allows you to review associations between all storage entities available
in vCenter and analyze storage usage.

Reports are updated every 30 minutes.


Use VMFS 3 datastores whenever possible

VMFS is optimized for storing and accessing large files

A VMFS can have a maxi
mum volume size of 64 TB (32 x 2
512k extents)

Offers some functions that NFS doesn’t support

Use RDMs if your VM is performing SAN snapshotting, is clustered using MSCS or has
large amounts of data that you don’t want to convert i
nto a virtual disk

You cannot store an RDM on an NFS datastore but you can store an RDM on a VMFS datastore

You cannot use MSCS to cluster a VM that resides on a NFS datastore

Overcommitted datastore


When there are many thin provisioned virtual disks
that use close
to their allotted disk space.

Increasing the size of a VMFS datastore

Add an extent to the VMFS datastore. You can add any extent to any VMFS datastore up
to 32 extents

Expand the VMFS datastore. Increase the size of the VMFS datastore
within its extent if
it has free space

To expand a RDM’s underlying raw LUN on the array, you have to remove the RDM and re
create it

Deleting a VMFS datastore permanently deletes the pointers to the files on the datastore, so
the files cannot be retriev

Multipathing allows continued access to SAN LUNs in the event of hardware failure and also
provides load balancing

Hardware iSCSI


Use 2 or more hardware iSCSI adapters

Software or dependent hardware iSCSI


Use multiple NICs

onnect each NIC to a separate VMkernel port

Associate VMkernel ports with
iSCSI initiator

so that each VMkernel port connected
to a separate NIC becomes a different path

Multiple paths can exist to a datastore on an ESX/ESXi host

Click the host’s


Click the


Right click the datastore and select

Click Manage Paths

Path selection policies


The host always uses the preferred path to the disk when that path is available.
Fixed is the default policy for active
active storage devices.

Most Recently Used

The host uses the most recent path to the disk until this path
becomes unavailable.
host does not revert back to the preferred path. Most
Recently Used is the default and required type for active
passive storage devices.

Round Robin

The host uses a path
selection algorithm that rotates through all
available paths. RR supports load balan
cing across the paths.

Pluggable Storage Architecture (PSA)

A VMkernel layer responsible for managing multiple storage paths

A collection of VMkernel APIs that allow third party vendors to insert code directly into
the ESX/ESXi storage I/O path (multipath
ing plug
ins MPPs)

VMware provides a generic M
P by default called Native Multipathing Plug
in (NMP)

When naming VMs, its best practice to avoid using special characters including spaces in the
name since the VM name is used to name the files that make
up the VM.

Files that make up a V
irtual Machine


Virtual machine configuration file


File describing virtual disk characteristics


allocated virtual disk file that contains the data


Virtual machine BIOS



Virtual machine log file and files containing old virtual
machine log entries


Virtual machine swap file


File that describes the virtual machine’s snapshots


Virtual machine template configuration file

If a VM is converted to a template, a virtual machine template configuration file (.vmtx)
replaces the virtual machine configuration file (.vmx)

If a VM has more than one disk file, the file pair for the

second disk file and later is



where # is the next
number in the sequence starting with 1.

6 of the archive log files are maintained at any one time. Name
1.log, name
2.log etc.

A virtual disk consists of
2 files

The .vmdk files which describes the virtual disk’s characteristics


flat.vmdk file which contains the virtual disk’s data

The datastore browser only shows the .vmdk file

You can add multiple USB devices to a VM that resides on an ESX/ESXi host t
o which the device
is physically attached. The device is only available to VMS that reside on that host. A USB device
is available to only one VM at a time.

VMware virtual SNP allows you to take advantage of configuring a virtual machine with up to 8
ual CPUs, allowing larger CPU
intensive workloads to run on ESX/ESXi hosts.

Adding the first virtual disk to a VM implicitly adds a virtual SCSI adapter for it to be connected.
ESX/ESXi offers a choice of adapters:

BusLogic Parallel

LSI Logic Parallel


Logic SAS

VMware Paravirtual

Independent disk mode


Use if you want changes to be immediately and permanently written to disk


Use if you want to discard changes when the VM
powered off or
reverted to a snapshot

Virtual Machine Network Adapters


Functions as a

adapter i

VMware tools is not installed on the VM. It
functions as a

driver if VMware tools are installed on the VM


An emulated version of the AMD 79C970 PCnet32 LANCE NIC. Drivers
available in most 32 bit operating systems


A virtual network adapter that has no physical counterpart or vendor drivers
and is optimized for performance in a VM. The VM needs

to have VMware tools


An emulated version of the Intel 8254EM Gigabit Ethernet NIC with drivers
available in most newer operating systems. It’s the default adapter for 64 bit guest
operating systems.

vmxnet2 (Enhanced vmxnet)

Based on t
he vmxnet adapter but provides high
performance features commonly used on modern networks such as jumbo frames and
hardware off


The next generation of paravirtualized NIC designed for performance. It’s not
related to vmxnet or vmxnet2. It

offers all the features of vmxnet2 plus multiqueue
support (Receive
Side Scaling in Windows), IPv6 off
loads, MSI/MSI
X interrupt delivery,
fault tolerance and record/replay. Only supported by a limited set of guest operating
systems and only available on

VMs with hardware version 7

The virtual CD/DVD drive can point to:

The CD/DVD drive or floppy drive of the ESX/ESXi host


image or floppy (.flp) image

The CD/DVD or floppy on your local system

Features of VMware Tools

Device Drivers




Bus Logic SCSI driver




Balloon driver for memory management


Sync driver for quiescing I/O


VMware mouse driver

Virtual Machine Heartbeat

Time Synchronization

Ability to shut down a virtual machine

VMware Tools control panel

Scripts to
help automate guest operating system operations

VMware user process

lets you copy/paste

Virtual Appliances

Typically includes a preinstalled guest OS

VAs are deployed as an Open Virtual Machine (OVF) template.

To import VA go to
File>Browse VA marketp

then complete the deploy OVF
template wizard to download it and add it to the vCenter Server inventory

vSphere client allows you to import and export any file in OVF format

Specify OVF filename or URL that points to the file

orting VMs allows you t
o create

virtual appliances that can be imported by other

VMs can be changed into templates without the need to make a full copy of the virtual machine
files and the creation of a new object

You can create a template by:

Cloning a VM to a template

Converting a VM to a template

Cloning a template

When you clone a VM to a template, the original VM is maintained.

When you convert a VM to a template, the original VM is replaced by the template.

When you clone a template, you make a copy of a template.


to Template offers you the choice of format in which to store the VMs virtual disks

Same format as source

Thin provisioned disk

Thick format


to Template does not offer a choice and leaves the VMs disk file intact.

View templates from the
VMs and Templates inventory view or from Hosts and Clusters view by
selecting a container and clicking its Virtual Machines tab.

To deploy a VM from a template, right click the template and choose
Deploy Virtual Machine
from this Template

To convert a t
emplate to a VM, go to the VMS and Templates inventory view. Right click the
template and select
Convert to Virtual Machine
. You can also use the vCenter Update

You can’t clone a VM if connected directly to an ESX/ESXi host.

When you clone a V
M that is powered on, services and applications are not automatically
quiesced when the VM is cloned.

When you clone a VM or deploy from template, you can customize its guest OS

Use the Guest Customization wizard during cloning or deployment.

Or create customization specifications and apply to the new VM

vCenter must be configured for customizations

For Windows 2000, XP and 2003 you must install the Sysprep tools on the vCenter

Sysprep tools are built into Vista and 2008

You can provis
ion VMs across datacenters in vCenter. You can also create a template in one
datacenter and then deploy a VM from that template into a different datacenter.

vCenter Converter tasks

Converts physical machines to VMSs

Convert and import VMs created by
VMware Workstation or Microsoft Virtual Server

Convert third party backup or disk images to vCenter VMs

Restore VMware Consolidated Backup images to vCenter VMs

Export vCenter VMs to other VMware VM formats

Reconfigure vCenter VMs so they are bootable

Customize vCenter VMS

vCenter Converter Components

vCenter Converter Server

Enables the import and export of VMs . Install it on a
vCenter Server or an independent server with access to vCenter Server

vCenter Converter agent

Prepares a powered on phy
sical or virtual machine for

vCenter Converter client

Plugin which provides access to the vCenter Converter
Import, Export and Reconfigure wizards from the vSphere Client.

Converter and Converter Client only run on Windows

Converter supports Windo
ws and Linux for importing and exporting

Installation file


vCenter Converter client


vCenter Converter server


vCenter Converter agent


When performing a hot clone
live clone
, vCenter Converter requires 350MB on the
source machi

vCenter Converter supports only pure IPv4 or IPv6 environments and the source,
destination and vCenter Converter server and agent must run the same version of IP

vCenter Converter uses cloning and the destination virtual disk might not be an exact copy

the source disk

4 stages of hot cloning performed by vCenter Converter

Preparing the source machine for conversion


vCenter Converter installs the vCenter Converter

agent on the source machine


The agent then takes a

snapshot of the source volume


vCenter Converter creates the snapshot with Microsoft’s Volume Snapshot
Service (VSS)

Preparing the VM on the destination machine


vCenter Converter creates a new VM on the destination ESX/ESXi host

Completing the conversion process


vCenter Converter instal
ls required drivers to allow the OS to boot in the virtual

Cleaning Up


The agent removes all traces from the source machine. The VSS snapshot
created in stage one is deleted and the
vCenter Converter agent is uninstalled
from the source

The Impor
t Machine wizard allows you to import from the following sources

Powered on machine (physical or virtual)

VMware infrastructure VM

VMware Workstation or other VMware VM

Backup image or third party VM supported by vCenter Converter

V Server VM

Data i
s copied to the destination using volume
based or disk
based cloning

during importing

based cloning


Used for hot cloning and importing existing VMs


All volumes in the destination VM are basic volumes regardless of the source


Volume based
cloning at the file level is when you specify a size smaller than the
original volume


Volume based cloning at the block level is performed when you specify the same
or a larger volume



Supports all types of source volumes that Windows recognizes

ased cloning


Transfers all sectors from all disks and preservers all volume metadata


The destination VM receives the same partitions, of the same type, as the
partitions of the source VM


All volumes on the source machine’s partitions are copied as they are


Disk based cloning supports all types of basic and dynamic disks

VM importing supports basic
and dynamic volumes except RAID
, Windows NT 4 fault

GUID partition table volumes.

Importing services

You can select which services to stop before v
Center Converter synchronizes the data
between the source and destination machine.

You can transfer data for the second time by copying only the changes made during the first
transfer of data. This process is called synchronization.

Only available for Wi
ndows XP or later
source operating systems.

Settings that remain identical include operating systems configuration, computer name, SID,
user accounts, profiles, preferences, applications and data files, and the volume serial number
for each disk partition

Modifying VM Settings

CPU hot plug

add CPU and memory to a VM while its powered on (enabled by default)

You must install VMware Tools and the VM must use hardware version 7 or later

The guest OS in the VM must support CPU and memory hot plugging

hot plug option must be enabled in the Options tab of the VM’s properties

You can increase the size of a virtual disk that belongs to a VM that is powered on if it is a flat
virtual disk in persistent mode and the VM does not have snapshots.

Raw Device
Mapping (RDM)

When you create a raw device mapping, vCenter Server creates a file in the specified
VMFS volume that points to the raw LUN

Encapsulating disk information in the file (the RDM) allows the VMkernel to lock the
LUN so that only one virtual mach
ine can write to it.

An RDM supports 2 compatibility modes:


Physical Compatibility mode

Allows the guest OS to access the hardware directly. Useful if you are
using SAN
aware applications in the VM

Cannot be cloned, made into a template or migrated if the
involves copying to the disk


Virtual Compatibility mode

Allows the VM to use VMware snapshots and other advanced

Allows the LUN to behave as if it were a virtual disk

Can be cloned or made into a template (content of LUN copied to

virtual disk file


Virtual Machine Snapshots

Organized in a linear process or as a process tree

Linear Process

Each snapshot has one parent and one child, except for the last
snapshot which has no children

Process Tree

Each snapshot has one

parent, but one snapshot can have more than
one child

A snapshot captures the entire state of the VM at the time you take the snapshot including:

Memory State

The contents of the VMs memory (if powered on)

Settings State

The VMs settings

Disk State

The state of all the VMs disks

In the Snapshot Manager you can do 3 things:


Commits the snapshot data to the parent snapshot and then removes the
selected snapshot

Delete All

Commits all the intermediate snapshots before the current state icon (You
are here) to the base disk and removes all snapshots for that VM

Go to

Allows you to restore, or revert to, a particular snapshot. The snapshot you
restore to becomes the curren
t snapshot

A virtual machine

can have one or more snapshot
. Each snapshot consists of:

Memory state file



where # is the next numb
er the
sequence starting with 1

Snapshot description file


This file is a

small text file that
contains information about the snapshot

Snapshot delta file


This file contains changes to
the virtual disk’s data at the same time the snapshot was taken


is the snapshot list file, creat
ed at the time the VM is created. It contains
information about all the snapshots that belong to the VM. This information includes the name
of the snapshot

file and the name of the virtual disk file

To create a vApp, use the New vApp wizard and then

modify its settings

Resource allocation

Determines how CPU and memory should be allocated for the

IP allocation policy

Determines how IP addresses are allocated for the vApp


Fixed (static)





IP addresses are automatically allocated

using IP pools from a
specified range

The distribution format for a vApp is OVF

When you delete a VM from a datastore, it is removed from vCenter Server and all VM files are
deleted from the datastore

Concurrent VM migrations

A host can be involved in up to

migrations with vMotion or Storage vMotion at one

A maximum of

simultaneous vMotion, cloning, deployment, or Storage vMotion
access to a single

datastore is supported


Maximum of
for a



Comparison of Migration Types

Storage Tiering

Migrating VMs from Fibre Channel to iSCSI or NAS or within or between
enclosures with Storage vMotion

Upgrading datastores without VM downtime with Storage vMotion

You can migrate running VM
s from a

datastore to a

datastore and
upgrade the VMFS
2 datastore without affecting VMs

Storage vMotion limitations:

VMs with snapshots cannot be migrated with Storage vMotion

VM disk must be in persistent mode or be RDMs

You can’t do a v
Motion and Storage vMotion at the same time with the VM powered on

Access Control

Defined with the following concepts


The ability to perform a specific action or read a specific property


A collection of privileges


An entity upon which actions are performed

User or Group

A user or group who can perform the action

The combination of a role, a user or group and an object equals a

Users who are in the Active Directory group ESX Admins are automatically
assigned the
Administrator role. On ESXi you can use the Direct Console User Interface (DCUI) and technical
support mode to log in with AD accounts.

vCenter Server and ESX/ESXi hosts manage their own set of roles. A role that is created on the

vCenter S
erver is

visible to an ESX/ESXi host if a user logs in directly to a host.

A role is assigned to a user or group

All roles are independent of one another

Objects are entities on which actions are performed

Objects include datacenters, folders, resour
ce pools, clusters, hosts, datastores,
networks and virtual machines

All objects have a Permissions tab

This tab shows which user or group and role are associated with the selected object

To assign a permission:

Select a user

Select a role

Propagate the
permission to child objects (Optional)

You can view all of the objects to which a role was assigned and all of the users or groups who
were granted the roles (

You can override permissions set at a higher level by explicitly
setting different permissions for
a lower level object

When a user is a member of multiple groups, and these groups have permissions on the same
object in the inventory, the user is assigned the union of privileges assigned to the groups for
that object.

Permissions defined explicitly for the user on an object take precedence over a user’s group
permissions on that same object.

Mechanisms for optimizing virtual machine resource use (3 groups)

Mechanisms that are managed by the VMkernel

Mechanisms that ar
e used at the discretion of each virtual machine’s owner

Mechanisms that are used by the vSphere administrator to set policies for virtual

Resource management

is the allocation of resources from providers (hosts, clusters, and
resource pools) to
consumers (virtual machines)

Resources include CPU, memory, storage and

Resource allocation settings

CPU and memory is controlled by using


Storage I/O is controlled by using shares and limits

A virtual machine has
3 user defined settings that affect its CPU resource allocation:

CPU limit

defines the maximum amount of CPU, measured in megahertz, that this VM is

CPU reservation

defines the amount of CPU, measured in megahertz, reserved for the
VM when CPU cont
ention occurs


specify the relative priority or importance of a VM. If a VM has twice the CPU
shares as another virtual machine, it is entitled to consume twice as much CPU when
these VMs are competing for resources

Proportional Share

mechanism applies to CPU, memory, and storage I/O allocation. It
operates only when VMs are contending for the same resource


guarantee that a VM is given a certain amount of a resource

You can add shares to a VM while it is running, and it will ge
t more access to that
resource (assuming competition for the resource)

A virtual machine has 4 user defined
memory settings

that affect its memory resource

Available memory

is the amount of memory of given to the VM at the time it was

Memory limit

defines the maximum amount of virtual machine memory that can reside
in RAM, not to exceed available memory

Memory reservation

is the amount of RAM reserved for that VM. Unused memory
reservations, like CPU reservations, are not wasted

emory shares

control how often it wins competition for RAM when RAM is scarce

Storage I/O Control

provides quality of service capabilities for storage I/O in the form of I/O
shares and limits that are enforced across all virtual machines accessing

a datas
tore, regardless
of which host they are running on

When you allocate storage I/O resources, you can limit the input/output operations per second

that are allowed for a virtual machine.

Configuring Storage I/O Control is a 2 step process:

Enable St
orage I/O Control for each datastore that you want to control

Set the number of storage I/O shares and upper limit of IOPS for each VM

By default, all VM share are set to
Normal (1000),

with unlimited IOPS

Resource Pool

is a logical abstraction for hierarchically managing CPU and memory resources

It is used on standalone hosts or clusters enabled for VMware Distributed Resource
Scheduler (DRS)

The topmost resource pool is called the
root resource pool
. Each standalone h
ost and each DRS
cluster has an (invisible) root resource pool that groups the resources of that host or cluster.

The root resource pool does not appear, because the resources of the host (or cluster)
and the root resource pool are always the same

A vApp

is not only a container for VMs but also a resource pool for its virtual machines

Benefits of resource pools:

Flexible hierarchical organization

Isolation between pools and sharing within pools

Access control and delegation

Separation of resources from

Management of sets of virtual machines running a multitier service

Resource pool attributes:


Low, normal, high and custom

in MHz and MB


in MHz and MB
(unlimited by default)

Expandable reservation



VMs and
subpools can draw from this pool’s parent



VMs and subpools can draw only from this pool, even if its parent has free

You can create a resource pool on an ESX/ESXi standalone host, DRS cluster, or in another
resource pool.

Except for the ro
ot resource pool, every resource pool has a
parent resource pool
. A resource
pool might contain child resource pools or only VMs that are powered on within it

child resource pool

is used to allocate resources from the parent resource pool for the child’
consumers. Administrative control can also be delegated to individuals or organizations. A child
resource pool cannot exceed the capacity of the parent resource pool. Creating a child pool
reserves resources from the parent pool, whether or not any virtu
al machines in the child pool
are powered on.

Expandable reservation

allows a resource pool that cannot satisfy a reservation to request
through its hierarchy to find unreserved capacity to satisfy the reservation request.

Admission Control

is used to en
sure that you cannot allocate resources that are not available.
Certain operations must satisfy admission control

Powering on a VM

Creating a resource pool with its own reservations

Increasing a resource pool’s reservation

The resource pool

tab di
splays information that applies to the host machine and its


pane displays basic information about VMs in the resource pool, as well as
child resource pools


pane displays host CPU usage


pane displays host memory usa


pane allows you to perform actions like creating a VM, creating a
resource pool, and editing a resource pool’s settings

Resource Allocation

tab allows you to display information about a resource pool’s
CPU, memory and storage resources

You can schedule a task to change the resource settings for a resource pool or virtual machine

You can configure a

with up to

virtual CPUs. The VMkernel include

a CPU scheduler that
dynamically schedules vCPUs on the physical processor of the host system.

Hyperthreading provides more logical CPUs on which vCPUs can be scheduled. It does not
double the power or a core. Hyperthreading is enabled by default. You can enable
in the system BIOS.

Logical processors on the same core have adjacent CPU

numbers. Logical processors 0 and 1 are
on the first core together; logical processors 2 and 3 are on the same core, and so on.

Every 2
40 milliseconds (depending on the socket
thread topology), the VMkernel looks to
migrate vCPUs from one logical p
rocessor to another to keep the load balanced. The VMkernel
does its best to schedule virtual machines with multiple vCPUs on 2 different cores rather than
on 2 logical processors on the same core.

For ESX hosts only, the service console always runs on th
e first logical processor and is never
migrated to another one.

If a logical processor has no work, it is put into a halted state. This action frees its execution

The VMkernel manages a machine

s entire memory

Part of this memory is used by t
he VMkernel

Some of this memory is used by the service console (ESX only)

The rest is available for use by VMs (configured memory, plus overhead)

VMS can use more memory than the physical machine has available (

Memory compression


virtual machine performance when memory is overcommitted.

When memory becomes overcommitted, virtual pages are compressed and stored in

Compressed memory is faster to access than memory swapped to disk

Enabled by default

When a host’s memory becom
es overcommitted, ESX/ESXi compresses virtual pages
and stores them in memory

Accessing compressed memory is faster than accessing memory that has been swapped
to disk

The Service Console typically uses 300MB

The VMkernel dynamically scans memory to look for duplicate pages. The VMkernel detects
when different virtual machines have memory pages with identical content and arranges for
those pages to be shared.

That is, a single physical page is mapped into each
VM’s address
space. If a VM tries to modify a page that is shared, the VMkernel creates a new, private copy
for that VM and then maps that page into the address space of that VM only. The other VMs
continue to share the original copy.


Balloon Driver

efers to the

device driver

Used to perform memory deallocation or reallocation

Installed on the guest OS when you install VMware Tools

It demands memory from the guest OS and later to relinquishes it under the control of
the VMkernel

When a syste
m is not under memory pressure, no VM’s balloon is inflated. But when
memory becomes scarce, the VMkernel chooses a VM and inflates it balloon telling the
balloon driver in the VM to demand memory from the guest OS

VMkernel Swap File

Each VM has its own

reated when the VM is powered on and deleted when it’s powered off

Default location is the same VMware vStorage, VMFS volume as the VM’s boot disk.

Size is equal to the difference between the memory guaranteed to it, if any, and the
maximum it can use

ws the VMkernel to swap out the VM’s machine entirely if memory is scarce

Used as last resort since performance is slow

If a VM can’t get enough memory through ballooning, the VMkernel forcibly reclaims memory
from other VMs. The VMkernel copies the conten
ts of the pages of these VMs to their
corresponding swap files before giving the pages to the VM that needs memory.

By default,
up to 65%

of a VM’s memory can be taken away in the ballooning process, subject
to the memory reservation settings.

VMware Too
ls includes a library of functions called the
Perfmon DLL

Perfmon allows you to access key host statistics in a guest VM.

The Perfmon performance objects (
VM Processor

VM Memory
) allow you to view
actual CPU and memory use alongside observed CPU and

memory use of the guest OS.


to display charts for the most common data counter for CPU, disk,
memory, and network metrics.


to view data counters not supported in the overview performance
charts, to export chart data, and to print charts.

The key to interpreting performance data is to observe the range of data from the guest
operating system, the virtual machine, and the host’
s perspective

Multiple Virtual Machines are

by CPU if:

There is high CPU use in the guest OS

There are relatively high CPU ready values for the VMs

Ready Time

refers to the interval when a VM is ready to execute instructions but cannot,
because it cannot get scheduled onto a CPU

When a VM experiences ballooning activity, some of the guest operating system’s physical
memory is being reclaimed from the VM by the

balloon driver. If a VM experiences high
ballooning values, this might not be a problem if the VM continues to have the memory that it
needs. But if a VM experiences high ballooning activity over time and its guest operating system
stars to page, the VM m
ight be constrained for memory.

Monitoring for increases in active memory on the host

Host active memory

refers to active physical memory used by virtual machines and the

If amount of physical memory is high, this could lead to VMs that are memor

intensive applications can saturate the storage or the path. If you suspect that a VM is
constrained by disk access:

Measure the throughput and latency between the virtual machine and storage

Use the advanced performance charts to monit


Read rate

write rate


Read latency

write latency

If you select a host object, you can view throughput and latency for a datastore, a storage
adapter, or a storage path. The storage

charts are only available for Fibre Channel
storage. The


charts are available for Fibre Channel and iSCSI storage,


To monitor
, view the
Read rate

Write rate

counters. To monitor
, view
Read latency

Write latency


Find disk problems by monitoring disk

latency and data counters

Kernel Command Latency


Measures the average amount of time, in
, that the VMkernel
spends processing each SCSI command


For best performance, the value should be 0
1 milliseconds

Physical Device Command Latency


s the average amount of time, in
, for the physical device to
complete a SCSI command


Depending on your hardware, a number greater than 15 milliseconds indicates
that the storage array might be slow or overworked

If you suspect a VM is cons
trained by the network:

Confirm that VMware Tools is installed and that the
enhanced network drivers


Measure the effective bandwidth between the VM and its peer system

Check for dropped
receive packets

and dropped
transmit packets

To determine whether packets are being dropped, use the advanced performance
charges to examine the


network counter values of a VM


The predefined alarms are configurable

To create an alarm, right click an object in the inven
tory and select
Alarm>Add Alarm

The Alarm Settings dialog box has 4 tabs:


In the

tab, you name the alarm, give it a description,
enable or disable the
give it an alarm type

and select what to monitor


Monitor for specific conditions or state


Create conditions based alarms for VMs, hosts and datastores


Monitor for specific events occurring on this object


Create event based alarms for VMs, hosts, clusters, datacenters, datastores,
networks, distributed vi
rtual switches, and distributed virtual port groups



Alarms have 2 types of
: condition or state triggers and event triggers

Condition or State Triggers


Monitor the current condition or state of virtual machines, hosts and


nditions or states include power states, connection states, and
performance metrics such as CPU and disk usage

Event Triggers


Monitor events that occur in response to operations occurring with a
managed object in the inventory or the vCenter Server itself

If you add multiple triggers, you can choose to trigger the alarm if any one of the conditions is
satisfied or if all the conditions are satisfied

Reporting tab

Used to define a tolerance range and trigger frequency for condition or state triggers
available for event triggers)

Reporting further restricts when the condition or state trigger occurs. You can specify a

or a


If using a range, the triggered alarm is repeated when the condition exceeds the


If using a frequency, the tr
iggered alarm is repeated every so often (in minutes)

Actions tab

Every alarm can send a notification email, send a notification trap, or run a command

You can set alarms to trigger when the state changes:


From a green circle to a yellow triangle


From a
yellow triangle to a red diamond


From a red diamond to a yellow triangle


From a yellow triangle to a green circle


For every action, you can specify an option for each color transition:

Empty indicate

no interest in the transaction

Once tells vCenter to do

the action only one time

Repeat tells vCenter to repeat the action until another color change
occurs. The default if 5 minutes and the maximum is 2 days

Virtual machine and host alarms have more actions such as:


Power on a VM


Power off a VM


Suspend a VM


eboot host


Shut down host

You can configure up to 4 receivers of SNMP traps.


They must be configured in numerical order


Each SNMP trap requires a corresponding host name, port and community

Data Protection

After you configure, change the configuration,
or upgrade an ESXi host, backup your

The serial number is backed up and restored when you restore your configuration

The serial number is not preserved when you run the recovery CD (ESXi Embedded) or
perform the repair operation (ESXi Install

Use the

command to do the backup from the vCLI from Windows or

Use the recovery CD or the repair option if the host does not boot up because the file
partitions or MBR on the installation disk might be corrupted

Use the followi
ng methods when backing up the Service Console:

File backed backup


Treat the service console a

a physical machine with a deployed backup agent

Image based backup


Use third party software to create a backup imaged that you can restore quickly

Machine Backups

VMware Consolidated Backup (VCB)

Used with supported third party software to do backups of virtual machine disks.

Centralizes backup on the VCB proxy server

VCB is the previous generation backup technology (vStorage APIs for Data Protection

and Data Recovery is most current)

vStorage APIs for Data Protection

Allows backup and recovery o

entire VM images across SAN storage or LANs

Is an easy
Smart Plug
in (

that is directly integrated with backup tools from third
party vendors

you to remove load from the host and consolidates backup load onto a central
backup server

Protects VMs that use any type of storage supported by ESX/ESXi (Fibre Channel, iSCSI,
NAS or local storage

Part of a larger set of APIs know as vStorage APIs and co

of the following sets:


Site Recovery Manager


Array Integration




Data Protection

Data Recovery


Agentless disk based backup and recovery appliance

Based on the vStorage APIs for Data Protection

VMware vCenter plugin

up to

appliances per vCenter Server instance

Supports up to

VMs per appliance

Intended for small to mediums sized environments

Different backup appliances do not share information about backup jobs

All backed up VMs are stored in a deduplicated
store. The deduplicated store can be
stored in a VMFS, RDM, NFS, or Common Internet File System (CIFS) share

Requires an absolute minimum of 10GB of free space

Need Essentials Plus, Advanced, Enterprise or Enterprise Plus licensing

VDR components communic
ate with each other over TCP


Connects to vCenter Server Web services on ports



Client plugin and File Level Restore connect to the backup appliance over port


The backup appliance connects to an ESX/ESXi host over port


RDMs are recommended for deduplication stores

To maximize deduplication rates, ensure that similar VMs are backed up to the same

The deduplication store completes the following processes:


Integrity check

Verifies and maintains dat
a integrity

VDR completes an incremental integrity check every 24 hours

VDR performs an integrity check of all restore points once a week



Ensures that the catalog of restore points is synchronized with the
contents of the deduplication store



Reclaims space on the deduplication store

Runs daily or when a backup job requires more space than is available on
the deduplication store

Supports dedupl
ication stores that are up to

in size on VMDKs and RDMs and
on CIFS shares

Each backup a
ppliance is limited to using 2 deduplication stores

VDR installation

Install the client plugin

Install the backup appliance

Add a hard disk to the backup appliance


Power on the appliance and change the root password

Configure network
settings, and reboot if necessary

Connect the appliance to the vCenter Server

Configure the backup destination on the appliance

Default username is

and password is

VDR backup jobs

A maximum of

jobs can run simultaneously

Backup jobs can backup

VMs total

By default, backup jobs run at night Monday through Friday and at any time Saturday
and Sunday

Rehearsal Restore

Used to test how a VM would be restored through restore operations

Does not replace the current VM

Level Restore

Can be installed in Windows or Linux VMs

Requires administrator privileges

Not supported on physical machines

vCenter Linked Mode

Log in simultaneously to all vCenter Server systems

View and search the inventories of all vCenter Server

You cannot migrate hosts or VMs between vCenter Server systems in Linked Mode

Can have up to

linked vCenter Server systems

Can have up to

hosts across the linked vCenter Server systems


powered on VMs and

registered V
Ms across linked vCenter
Server systems

Uses Microsoft’s Active Directory Application Mode

to store and synchronize
data across multiple vCenter Server instances

Using peer to peer networking, the vCenter Server instances in Linked Mode replicated
hared global data to the LDAP directory

The vSphere Client can connect to other vCenter Server instances by using the
connection information retrieved from ADAM.

Apace Tomcat Web service

running on vCenter Server enables the search capability
across m
ultiple vCenter Server instances

For inventory searches, vCenter Linked Mode relies on a Java based Web application
called the
query service
, which runs in Tomcat Web services

The search service queries Active Directory for information about user permissio
ns. So
you must be logged in to a domain account to search all vCenter Server systems in
vCenter Linked Mode

When adding a vCenter Server instance to a Linked Mode group, the user running the installer
must be a local administrator on the machine where vC
enter Server is being installed and on
the target machine of the Linked Mode group. Generally, the installer must be run by a domain
user who is an administrator of both systems

The following requirements apply to each vCenter Server system that is a mem
ber of a Linked
Mode group:

DNS must be operational for Linked Mode replication to work

The vCenter Server instances in a Linked Mode group can be in different domains if the
domains have a 2 way trust relationship. Each domain must trust the other domains

which vCenter Server instances are installed

All vCenter Server instances must have network time synchronization. The vCenter
Server installer validates that the machine clocks are no more than 5 minutes apart

Install the first vCenter Server instance

as a standalone instance

The vCenter Server instances in a Linked Mode group do not need to have the same domain
user login

During vCenter Server installation, if you enter an IP address for the remote instance of vCenter
Server, the installer converts
it into a fully qualified domain name

To join a vCenter Server system to a Linked Mode group click on
Start>Programs>VMware>vCenter Server Linked Mode Configuration

vCenter Server Status

shows information such as:

A list of all vCenter Server systems and

their services

A list of all vCenter Server plugins

The status of all listed items

The data and time of the last change in status

Messages associated with the change in status

Roles are replicated when a vCenter Server system is joined to a Linked Mode g

If role names differ on vCenter Server systems, they are combined into a single common
list and each server will have all the user roles

If role names are identical, they are combined into a single role if they have the same

If role names a
re identical, and the roles contain different privileges, these roles must be

Use the vCenter Server Linked Mode Configuration wizard to isolate (remove) a vCenter Server
instance from a Linked Mode group

Start>Programs>VMware>vCenter Server Li
nked Mode Configuration

Click Modify linked mode configuration and click Next

Click Isolate this vCenter Server instance from linked mode group

Host Profiles

Basic workflow to implement host profiles:


Setup and configure a host for a reference


Use the
Create Profile wizard to create a profile from the designated reference


Attach the host or cluster to the profile


Check the host’s compliance against a profile to ensure that the host continues
to be correctly configured


Check new hosts for compliance

against the host profile. You can easily apply the
host profile of the reference host to other hosts or clusters of hosts that are not
in compliance

You can also import and export a profile file to a host profile that is in the VMware profile
format (.vp

After the host profile is created and associated with a set of hosts or clusters, you can check the
compliance status from various places in the vSphere Client

Host Profiles main view

Displays compliance status of hosts and clusters, listed by

Host Summary tab

Displays compliance status of the selected host

Cluster Profile Compliance tab

Displays compliance status of the selected cluster and
all the hosts within the selected cluster

Whenever a new host is added into a cluster, it is check
ed for compliance against the host
profile that has be


You can also schedule tasks in vSphere to help automate compliancy checking

To apply a host profile:

Go to Home>Management>Host Profiles

Select the host profile in the inventory and click
the Hosts and Clusters tab

Right click the host and select Apply

vNetwork Distributed Switch

vCenter Server owns the configuration of the distributed virtual switch. The
configuration will be consistent across all the hosts that use it

A distributed virtual switch can support up to


A distributed virtual switch can benefit from the performance of 10GbE physical NICs


support for private VLANs


ports migrate with their clients

Private VLANs

allow you to use VL
AN IDs within a private network without having to worry
about duplicating VLAN IDs across a wider network

Some configuration is specific to the host. A host’s uplink ports are allocated to the distributed
virtual switch and are managed in the host’s networ
k configuration. Similarly, the VMkernel and
service console ports are managed in the host’s network configuration as well.

You connect a virtual machine to a distributed virtual switch by connecting the VMs NIC to a
port group on the distributed virtual

A distributed virtual switch is a managed entity configured in vCenter Server

Each distributed virtual switch includes distributed ports. A distributed port represents a port to
which you can connect any networking entity, such as a VM, a VMkernel

interface, or a service
console interface (ESX only)

Ports can exist without port groups

An uplink is an abstraction to associate the vmnics from multiple hosts to a single distributed
virtual switch

VMs on different hosts can communicate with each oth
er only if both VMs have uplinks on the
same broadcast domain

The distributed virtual switch architecture consists of 2 planes: the

and the I

The control plane resides in vCenter Server and is responsible for configuring distributed
virtual switches, distributed port groups, distributed ports, uplinks, NIC teaming etc.

The I/O plane is implemented as a hidden virtual switch in the VMkernel of each
ESX/ESXi host. The I/O plane manages the I/O hardware on the host and is responsible

forwarding packets

Editing general switch properties

The settings dialog box has 3 tabs:
Network Adapters

Private VLAN

The Network A
dapters tab is a read only form

that allows you to verify which physical
adapters are connected to the dis
tributed virtual switch

The Private VLAN tab allows you to setup private VLANs for the distributed virtual switch

The Network Adapters and Private VLAN tabs are only available for distributed virtual
switches, not for distributed ports or distributed port

Settings on the Properties tab are grouped into the categories General and Advanced.


for the distributed virtual switch allow you to edit the information
specified when creating the distributed virtual switch

Advanced properties

n the distributed virtual switch allow you to define the maximum
transmission unit (MTU), the Cisco Discovery Protocol (CDP) status, and the
administrator contact details


Maximum Transmission Unit

determines the maximum size of frames in this distributed
virtual switch. The distributed virtual switch drops frames bigger than the specified size. If your
environment supports jumbo frames, use this option to enable or disable jumbo frames on the
buted virtual switch. To enable
jumbo frames

on the distributed virtual switch, set the
Maximum MTU

to 9000. To use jumbo frames, the network must support it end to end.
ESX/ESXi supports jumbo frames in the gest OS and on VMkernel ports.


has 3 oper
ation modes:

Listen mode (default)

The ESX/ESXi host detects and displays information about the
associated Cisco switch port. But information about the virtual switch is not available to
the Cisco switch admin

Advertise mode


The ESX/ESXi host makes inf
ormation about the virtual switch
available to the Cisco switch admin

Both mode

does both

Network resource pools

determine the priority that different network traffic types are given on
a distributed virtual switch. By default, Network I/O Control is d
isabled. When Network I/O
Control is enabled,

distributed virtual switch traffic is divided into the following network
resource pools:

FT traffic

iSCSI traffic

vMotion traffic

Management traffic

NFS traffic

VM traffic

Network shares and limits apply to a
host’s outbound network I/O traffic only

To enable Network I/O Control

Go to Home>Inventory>Networking

Select the distributed virtual switch in the inventory and click the
Resource Allocation


Click the

link and select
Enable network I/O con
trol on this vDS

To modify the shares or limits of a particular network resource pool, right click the
resource pool and select
Edit Settings

vMotion Migration

The state information includes the current memory content and all the information that defin
and identifies the virtual machine

vMotion Migration consists of the following steps:


The VMs memory state is copied over the vMotion network from the source host to the
target host


After most of the VMs memory is copied from the source host to the