Transcript PVS-Comprehensive 6 0 Updatex

PVS –
Comprehensive Training
(230)
Christian Paller/Gerard Carragher
Support Readiness
Agenda
• Introduction
• Architecture
• vDisks
• Target Devices
• Server Administration
• Advanced Features
Introduction
Non-Provisioned Environments
Reserve Servers
(Hot Standby)
Active Servers
Physical Disks =
Call Center Apps.
Call Center
Agent Apps.
XenApp
XenApp
XenApp
XenApp
Web Server
Web Server
NAS or SAN
Citrix Provisioning Services Environments
Reserve Servers
(Hot Standby)
Active Servers
No Physical Disks =
Call Center Apps.
XenApp
XenApp
Web Server
vDisks
Call Center Apps.
XenApp
Web Server
“Stateless”
Reserve
Provisioning
Server Farm
NAS or SAN
Rollout / Rollback
Reserve Servers
(Hot Standby)
Active Servers
No Physical Disks =
Call Center Apps.
XenApp
XenApp
Web Server
vDisks
Call Center Apps.
XenApp
Web Server
“Stateless”
Reserve
Provisioning
Server Farm
NAS or SAN
XenApp
Benefits of Citrix PVS
• Manageability
• Simplify and streamline server provisioning
• Assure build consistency
• Eliminate the need for “hot-standby” servers
• Flexibility
• Provide rapid server provisioning
• Simplify and reduce the time required to rollout images
• Stream workloads to physical and virtual machines
• Support high availability
• Support hardware repurposing
• Perform instant restore
Licensing
PVS Licensing
Product
Version
Stream Server OS
Stream Client OS
XenApp
Platinum
Y
N
Enterprise
N
N
Advanced, Fundamentals
N
N
Platinum, Enterprise
Y
Y
Standard, Express
N
N
XenDesktop
Grace Periods
• Support out-of-box (OOBG) period of 96 hours in all
licensing models
• License server disconnects, 720 hour grace period for all
licensing models
• If no proper license and OOBG expired, target devices
receive shutdown warning message:
• PVS 5.1 – 5 minutes
• PVS 5.1 SP2 – 3 hours
• PVS 5.6.1 – 96 hours
• PVS 6.0 installation – 720 hours
Licensing KB Articles
• CTX117793 – PVS Grace Period Overview
• CTX117378 – PVS and License Server FAQ
Architecture
PVS Component Architecture
TCP: 27000
Server
Target
Devices
AD
LDAP: 389
I/O: 6910 - 6930
CIFS/NFS
TFTP: 69
ODBC
PXE: 66/4011
DHCP: 67
License
Server
Shared
Storage
DB (SQL)
DHCP Server
PXE Server
TFTP Server
Citrix PVS Farms
Provisioning
Services
Farm
MSSQL
Server
Database
License
Server
Site 1
Device
Collection
Provisioning Servers
Device
Collection
Device
Collection
Shared
Storage
Provisioning Servers
Site 2
Device
Collection
Device
Collection
Provisioning Server Components
Components
PXE Service
PXE Service
PVS PXE Implementation
Acts as DHCP Proxy to deliver
bootstrap location to target device (if
not using Windows DHCP Options
66/67)
Use this service if a DHCP service
exists, and can not be changed and
another PXE service is not used
Provisioning Server Components
Components
PXE Service
PVS Database
Configuration Database
PVS 6.0 uses a SQL Server database
for storing all configuration settings for
the farm
SQL Express can be used (for POCs)
Only one database per farm
Can be on separate server
Provisioning Server Components
Components
TFTP Service
PXE Service
Delivers the bootstrap program to a
target device request
PVS Database
Use if another TFTP server is not
available in the network
TFTP Service
Provisioning Server Components
Components
Streaming Service
PXE Service
Streams vDisk content to target
device
PVS Database
Manages client registration on boot
TFTP Service
Manages license check-out /check-in
Streaming Service
Sends write data from target device to
vDisk or write cache
Provisioning Server Components
Components
SOAP Service
PXE Service
Provides framework for console and
management CLI
PVS Database
Covers 100% of the product
TFTP Service
SOAP Server Programmer's Guide
Streaming Service
SOAP Service
Boot Process
Normal PC Boot Process (abridged)
Target Device
PC starts up
PVS Server
BIOS  POST
Identify boot device
Load operating system
Local HDD
vDisk
How Does A Target Device Receive A Streamed OS?
• Boot Process in Short
• Perform PXE Boot to boot from network
• Receive DHCP IP Address
• Receive name and location of a “Network Bootstrap Program”
• Download a small 10kb bootstrap NBP from specified location
• NBP install a BIOS Disk IO redirector and PVS protocol
• Provisioning Server delivers streamed OS from network location to target
device on demand as a block level disk device
Enabling PXE Boot
Receiving DHCP IP Address
• Device requires IP address to connect to network devices
(PVS server)
• Client sends DHCP broadcast as part of PXE boot process
• DHCP options:
• Windows DHCP (most common)
• Tellurian DHCP (included with PVS and can be used if Windows DHCP not
available)
• BOOTP (legacy option)
Retrieving Name/Location of Bootstrap Program
• Target devices need name and location of NBP
• TFTP server hosts bootstrap file (ARDBP32.BIN)
• Options for delivering name/location:
• DHCP Options 66/67
• PXE Service
• USB/CD-ROM
• An OEM Option ROM
Downloading Bootstrap Program
• TFTP Service provides NBP to target devices
• TFTP = Trivial File Transfer Protocol
• Bootstrap program includes name of up to four Provisioning Servers
Delivering Streamed OS to Target Device
• PVS Stream Service facilitates streaming
• vDisk is stored on Windows file share, SAN, NAS, or PVS server
• Ensure stream service has access to vDisk location
Normal PC Boot vs. PVS Boot
Target Device
PC starts up
PVS Server
BIOS  POST
Identify
PXE
boot
boot:
device
IP address
LoadGet
operating
system
Get NBP name / location
Get NBP
vDisk
NBP initializes
PVS login
Load operating system
PVS Login Sequence
Target Device
What Login IP:Port can I use?
Use this Login IP:Port
Login and HA reconnect
begins here
Login Server – Log me in; here’s my MAC address and
reconnect flag
OK – Use this least busy server using this contact port and
this disk ID on this device!
Additional processing
happens here (disk menu,
BIOS prompts, etc)
PVS
Farm
Least busy server – what IO port should I use?
Use this IO port
service my request for this disk on this device
All set – streaming now …
Non-HA reconnect
begins here
Streaming – The Whole vDisk?
Average Transferred Data (MB)
vDisk OS
Device Cache
Server Cache
XP SP2 x32
85
90
XP SP2 x64
110
115
2003 Server SP1 x32*
95
100
2003 Server SP1 x64*
120
130
Vista Enterprise x32
180
190
Vista Enterprise x64
220
240
Streaming – The Whole vDisk?
Average Transferred Data (MB)
vDisk OS
Device Cache
Server Cache
Windows 7 *86
156
166
Windows 7 *64
196
210
Windows 2008 *86
140
150
Windows 2008 *64
210
220
Windows 2008R2 *64
230
240
Farm Structure
Farms
• Provisioning Server farms:
• Are a grouping of Provisioning Servers
• Share a database
• Share a license server/license server VPX
Sites
• Sites typically represent:
• Physical sites
• Buildings
• Geographic locations
Stores
• Logical representations of physical location of vDisk folder
• Can exist on either local server or shared storage
• Can be one of several types
• Farm
• Site
• Single server
• Distributed server
• vDisk Pool: collection of vDisks available to a site
(One pool per site)
Farm Store
MSSQL
Server
Database
License
Server
Shared
Storage
Site 2
Site 1
WinXP
Store
\\192.168.0.103\vDisks
Provisioning Servers
Provisioning Servers
Server has been configured to provide the store and
UNC file path has been specified in Store Properties
Site Store
MSSQL
Server
Database
License
Server
Shared
Storage
Site 2
Site 1
WinXP
Store
\\192.168.0.103\vDisks
Provisioning Servers
Provisioning Servers
Server has been configured to provide the store and
UNC file path has been specified in Store Properties
Distributed Server Store
MSSQL
Server
Database
License
Server
Shared
Storage
Site 2
Site 1
WinXP
H:\vDisks
WinXP
H:\vDisks
WinXP
H:\vDisks
WinXP
H:\vDisks
Provisioning Servers
Server has been configured to provide the store in Store Properties,
and local path override has been configured in Server Properties
Single Server Store
License
Server
MSSQL
Server
Database
Shared
Storage
Site 2
Site 1
WinXP
H:\vDisks
Provisioning Servers
Provisioning Servers
Server has been configured to provide the store and
local file path has been specified in Store Properties
Device Collections
• Device collections typically represent
• Physical locations
• Subnet ranges
• Organization names
Administration Roles
Farm
Farm Administrators
Site
Site Administrators
Provisioning Servers
vDisk Pool
Device Collection
Device Collection
Target Devices
Target Devices
Device Administrators
Device Operators
Exercise – Install and Configure a PVS Farm
vDisks
Modes and Cache Types
vDisk Overview
• VHD File which contains a drive/OS to stream to target
device
• Can be stored on
• Network file share
• SAN/NAS
• Provisioning Server local DAS
• Administrator determines vDisk size upon creation
• Fixed or dynamic
• Server can view vDisk file as a removable drive
• vDisk is mounted and mapped to first available drive letter
Working With vDisks
Private Image Mode
A single image is streamed on boot to the
target device
User installs software or updates which are
written back to the vDisk real-time
Provisioning Server
Target Device
Network
Storage
The target device is shut down
On next boot, changes persist
Working With vDisks
Standard Image mode (Difference Disk mode)
Target Device 1
Server-Side Disk Cache
Device-Side Disk Cache
Provisioning Server
Target Device 2
Network
Storage
A
Target Device 3
A single vDisk is streamed to many target
devices
Any session changes are not written back to
the base vDisk
On reboot, a “clean” image is streamed
down to the target devices
Device-Side RAM Cache
Where do the "writes" go when using Standard Image mode?
Write Cache Considerations
• RAM Cache
• Best performance for single applications
• Possibility of overflow errors due to limited RAM
• Perform Server-based cache to estimate size requirement
• Client Disk Cache
• Low network traffic
• Required for full system dumps
• Most common in deployments
• Can be secured through encryption
• Server Disk Cache
• No requirement for local hard disk
• Can be secured through encryption
Environment Uniqueness
Things like:
My Documents
Desktop
Wallpaper
Start Menu
Target Device
Network
Storage
User Data
User Data
Tools:
Sepago, AppSense
Roaming Profiles
Hybrid Profiles
Folder Redirection
These tools help you store and configure the
user workspace outside the write-back cache
Machine Uniqueness
Target Device Personality feature
allows data for specific target devices
Custom Script
Made available at boot time
Custom Data
Information is stored in the database
Target Device
Network
Storage
Custom Data
Application Uniqueness
Target Device 1
Isolation
A single image is streamed to many target
devices
Applications can be streamed “on- demand”
to each target device…
Provisioning Server
Target Device 2
Network
Storage
Isolation
A
Target Device 3
Isolation
Application Streaming
Managing the Target Device Name at Runtime
MTD
TD1
TD2
TD3
High-level boot process for XP
Power-on Self Test
Master Boot Record
Boot Strap Loader (Ntldr)
Memory Addressing
File System
Boot Menu
Registry
Hardware Profile
Control Set
Device Drivers
WinLogon
Lsass
vDisk Administration
vDisk Pool
• Collection of all vDisks available to a site
• There is one vDisk Pool per site and it can reference many stores
vDisk (Un)Assignment
• Association between
target device and vDisk
• Does not make changes
to vDisk file
• Can be done when device is active
Deleting a vDisk
vDisk Lock Management
• Locks control access to vDisk files
• Prevent corruption of the vDisk
• Can be managed through the console
• Are released when a target device is shut down
• vDisk locks are not released if
• Target device fails
• Power to the target device is lost
• Target device is not shut down gracefully
Basic vDisk Properties: General Tab
vDisk File Properties: General Tab
vDisk File Properties: Mode Tab
vDisk File Properties: Identification Tab
vDisk File Properties: Options Tab
Copying Properties to Another vDisk
Target Devices
Master Target Device
Master Target Device
image
vDisk
Master Target Device
• Create "Golden Image"
• OS, apps, drivers, etc.
• PVS Target Device Software
• Add to console
• Target device boot order
• Always PXE boot
• Assign vDisk
• Private image mode
Exercise: Create a vDisk and Image the MTD
Adding Target Devices
Adding Target Devices Manually Within Console
• Specify Target Device Name - Description – MAC address
Comparing Methods for Adding Target Devices
Benefits
Considerations
Single Add
• Simplest method for adding single target
• MAC addresses need to be known beforehand
MCLI
devices
• Batch file allows multiple target devices to be
added at same time
• MAC addresses need to be known beforehand
• Great method for adding hundreds of devices
• Import file allows multiple target devices to be
need to be updated to 5.0 format
• MAC addresses need to be known beforehand
Import File
added at same time
• Great method for adding hundreds of devices
Auto-Add
• Batch files created for the 4.x MCLI utility will
• Console access required
• Admins can only add devices to device
demand
collections for which they have ownership of
• Target devices are given dynamic name based
on template name
• MAC addresses do not need to be known
• Admins need to add devices to domain before
beforehand
users can log in with domain accounts
• Target devices are auto-added to PVS on
Adding Target Devices using Auto-Add Feature
• Allows devices to be added dynamically during PXE boot
• Administrative control over how they are added
• Enable Auto-Add at the farm level - choose default site and collection
Adding Target Devices using Auto-Add Feature
• Auto-added devices are given a dynamic hostname based
on the template name
Target Device Properties
General Tab
Log level on server has to
be same or higher
Copying Target Device Properties
Domain Computer Accounts
Active Directory Integration
• Add MTD to domain before building vDisk image*
• Computer accounts for target devices can be created
• Using the Console
• Using the CLI
• CLI commands
• Run AddDeviceToDomain
• Run RemoveDeviceFromDomain
• Run ResetDeviceForDomain
Creating Domain Accounts Using the Console
Creating Domain Accounts Using the MCLI
Machine Account Passwords
• Domain members need name and password
• Problem: Automatic re-negotiation of passwords
• Turn off on domain or local level
• Let PVS manage domain passwords
Enabling Machine Account Password Management
Enabling Automatic Password Support
Enable Domain Policy
Citrix Confidential - Do Not Distribute
Exercise: Streaming to Multiple Target Devices
Citrix Confidential - Do Not Distribute
Server Administration
Basic Server Properties
Basic Server Properties Administration
• The Server Properties screen is separated by four tabs
• General
• Network
• Stores
• Options
• Changing server properties requires Stream Service restart
Basic Server Properties
Log level on client has to be
the same or lower
Copying Properties to Another Server
Advanced Server Properties
Network: Maximum Transmission Unit (MTU)
Pacing: Maximum Devices Booting
Pacing: Boot Pause Seconds
Pacing: vDisk Creation Pacing
Device: License Timeout
Server Logs
PVS 6.0 Server - Logs
Win2K8R2: C:ProgramData\Citrix\Provisioning Services\Log
Log Files
• StreamProcess.exe

Stream.log
• MCLI.exe

MCLI.log
• SoapServer.exe

SoapServer.log
• Console.exe

Console.log
• ConfigWizard.exe

ConfigWizard.log
• XenConvert.exe

XenConvert.txt
Network Bootstrap Program - Verbose Mode
Identify which part of
PXE Process is failing
Advanced Features
High Availability
High Availability
High Availability (HA) Overview
• Multiple Provisioning Servers are installed within a site
• Up to 4 Provisioning Servers facilitate login requests from target devices
• Up to 10 Provisioning Servers stream vDisks to target devices
• HA reconnect occurs after 10 failed requests to connect to vDisk
• Excludes rest of infrastructure
• SQL Server (Provisioning Server database)
• DHCP
• TFTP
• vDisk storage (Windows shares, NAS, SAN)
• Network devices (switches and routers)
Distributed HA
Centralized HA
Deployment Considerations
How HA Works …
Target Device
What Login IP:Port can I use?
Use this Login IP:Port
Login Server – Log me in; here’s my MAC address and
reconnect flag
OK – Use this least busy server using this contact port and
this disk ID on this device!
Least busy server – what IO port should I use?
Use this IO port please!
Thanks – please service my request for this disk on this
device
All set – streaming now …
PVS
Farm
General HA Share Requirements
• Supports different shared storage systems
• RAID, SAN, NAS, Windows shared storage
• Combination of the above
• Entire HA Cluster must have connectivity to the Share
• Streaming Service must run on each host
• Streaming Service account needs full control to access the share
• All servers must have access to the vDisks on the Share
• HA is based on a “native PVS clustering mechanism”
• No 3rd party clustering software is required for HA
Configuring the Bootstrap File
Target devices will choose
a random PVS server
If that PVS server is not
available round robin is
performed
Enabling a vDisk for HA
Configuring Access to HA Storage
Configuring NTFS Security Permissions
Testing HA Failover
Performance and Scalability
XenApp – Installed OS vs. Streamed OS
Streamed XenApp Server
XA 5 – Windows 2008
HP DL360G5
Single Intel Xeon 2.0 GHz Quad
Core Processor
8GB of RAM
2 internal 1GB network cards
EdgeSight for
Load Testing
Virtual user test setup
Physical XenApp Server
XA 5 – Windows 2008
HP DL360G5
Single Intel Xeon 2.0 GHz Quad
Core Processor
8GB of RAM
2 internal 1GB network cards
The Results….
• Average it took to run Excel script on each XenApp system
In the series of tests conducted no measurable impact on:
• User density
• Stability of a streamed XenApp environment
PVS – Server Scalability Test
Physical PVS Server
Different hardware
(754 devices total):
Dell 1750
Dell 1850
IBM 335
HP ML150
XenServer VMs
HP ProLiant DL360 G5
Two quad-core Intel Xeon CPU
E5335 @ 2.00GHz
16 GB FB-DDR2, PC2-5300
6 disks 72GB 15k configured as
C: 2 disks, RAID 0 array,
OS and PVS install
F: 4 disks, RAID 0 array,
local VHD store
2 HP NC373i Multifunction
Gigabit Server
DB on dedicated SQL server
5 vDisks to accommodate
different TD hardware
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% Utilization
CPU and Disk Utilization
XenApp servers under load
25
20
Findings:
Reduced CPU and disk utilization
while streaming single vDisk vs.
multiple vDisks
15
461 - % Processor Time
233 - % Processor Time
72 - % Processor Time
10
461 - % Disk Time
233 - % Disk Time
72 - % Disk Time
5
0
Provisioning Server Performance
Target servers use Provisioning Server as a proxy to access their virtual disk over the network. As a result,
there are a number of factors that can impact the performance of the deployment.
Network Performance
• Bandwidth
• Latency
Server Performance
• Number of NIC’s
• Number and Speed of CPU’s
• Amount of Memory
vDisk Storage Performance
• Number of Drives
• Drive Configuration
• Drive Cache
• Spindle Speed
• Latency
• Data Link (for shared
storage)
Additional Deployment
Configuration Variables
• Number Target Servers
per Server
• Number Concurrent
Boots
• Number of Active vDisks
• vDisk OS
A
Target Server
Provisioning Server
Network
Storage
Scalability documents
• CTX122296 – PVS and Storage Considerations
• CTX119286 – PVS High Availability Considerations
• CTX129992 – PVS 6.0 Release Notes
• CTX117922 – XenApp and XenServer – Reference
Architecture
• CTX120464 – Provisioning Services for XenApp Best
Practices
• CTX117378 PVS and License Server FAQ
vDisk Updates with PVS
Updating vDisk Images Pre-PVS 6.0
• Private Image – No different than hard drive
• Standard Image – Depends on mode of operations
• “Single Shift”
• “24 x 7”
• Basically, the idea is:
• Switch VDisk to Private Image mode
• Perform updates
• Switch VDisk back to Standard Image mode
• Clone the vDisk – perform the update and copy to new vDisk back over
Integrated vDisk Versioning
Updating a vDisk with PVS 5.6.1
Ver1.vhd
15.0 GB
Clone
Ver2.vhd
15.0 GB
15.1
15.2
15.3
Updating a Vdisk with PVS 6.0 – The New Model
vDisk.vhd
15.0 GB
Parent
vDisk.1.avhd
100
200
300
0 MB
MB
How does Versioning Work?
• New VHD types
• New vDisk lifecycle operations and modes
• New target device types
New VHD Types
The existing VHD file types are preserved
• Fixed
• Dynamic
New VHD types
• VHD Base Disk, *.vhd (either fixed or dynamic VHD)
• VHD Differencing disk, *.avhd
VHD Chains – Examples
VHD Chains – Read/Write Access
Properties & Lock Files
• Properties file for each version to retain printer configurations
• Cache type will be determined by top version
• Lock file will exist for each version
vDisk Lifecycle Management
• Maintenance
• Test
• Production
• Standard Mode
• Private Mode
New Target Device Types
• Maintenance
• Test
• Production
Lifecycle and VHD Chain Operations
• Lifecycle operations
• New
• Promote
• Revert
• VHD chain operations
• Merge (2 ways)
• Delete
• Replication (Import / Export)
vDisk Versioning User Interface
JoeAdmin: Adding latest sales support application.
vDisk Versioning User Interface
Icon Version
Maintenance
Test
Pending
Current Production
Obsolete
Creating a New vDisk Version
Lifecycle Operations - Promote
• Promotes a disk to
test or maintenance
• Can be immediate
or scheduled
Lifecycle Operations - Revert
• Reverts a
production to test
or maintenance
• Reverts a test into
maintenance
VHD Chain Operations - Merge
• Consolidate multiple
differencing disks into:
• Another differencing disk (consolidated)
• New base disk
• Can only be done if
• No Maintenance version exist
• No Test version(s) exists
VHD Merge – Consolidated Differencing Disk
VHD Merge – New Base Image
Automatic Merge
VHD Chain Operations – Import/Export
• Import and export of both versioned and unversioned
vDisks, from an existing store to a store in a different farm
• Import or Export of VHDs and VHD chains
• Treat disks from external sources as single VHD
• All differencing disks not exported with PVS must be merged
to a base disk before imported
Performance Considerations
• Performance
• The longer the VHD chain the more IOPS and memory it will consume
• Upgrade and backward compatibility
• Upgrade ALL SERVERS before using vDisk versioning
• Old target drivers specify versions are compatible with vDisk versioning
Class Attribute
Use the Class attribute to associate target devices with vDisks
Type Attribute
.
Associate current vDisk with updated vDisk
Enabling Automatic & Incremental VDisk Updates
Enable Updates on the Server
vDisk Serial Number
PVS 6.1 release
Release date: March 09th 2012 as part of (Project Ibiza)
6.1 release features include:
• Support for System Center 2012 (SCCM and VMM)
• Support for new Streamed with PvD catalog in XD Environs
• Support for vSphere 5
PVS 6.0 to 6.1 Upgrade best practise
• Upgrade your Servers first (Rolling upgrade) TD’s on
• Once Servers and consoles are upgraded, upgrade your
Target Device S/W
• Review all hotfixes that have been released after
CPV61E003 and apply as necessary
• Public Hotfixes for PVS:
http://support.citrix.com/product/provsvr/pvsv6.1/hotfix/gener
al/public/?sortBy=CREATIONDATE
FAQs
• Q: In Standard Image Mode, why is the write cache using
a lot of disk space?
• In Short: Every change means writing to the cache, even
deleting files, i.e. the cache can only grow
• Q: Will antivirus software installed on a Provisioning
Server impact the performance of the vDisk provisioning
and target device performance?
• Yes. VHD files should be excluded from real-time scanning.
• Q: How does Provisioning Services handle SID
uniqueness?
• It doesn't, because it's not necessary (see notes)
http://blogs.technet.com/markrussinovich/archive/2009/11/03/3291024.aspx
• Q: What is the necessary bandwidth required by
Provisioning Services?
• The following formula can be used to estimate the necessary
bandwidth
Boot time(s) = # of TDs * minimum dowload (MB) / NW througput (MB, not Mb)
• Q: Can the pre-boot services be made fault tolerant?
• DHCP Cluster
Two DHCP servers with different scopes (split scopes)
DHCP Stand-by Server
• Hardware-based load balancing (NetScaler)
• DNS round robin: use FQDN within DHCP option 66
• Provisioning Services PXE service
• TFTP on multiple PVS servers
• Multiple PVS servers in bootstrap
• Q: Why does Provisioning Services use UDP instead of
TCP?
• The UDP protocol is much simpler to implement with the
network stack being only 25% of a TCP stack. Because
Provisioning Services operates at such a low level, the
Provisioning Services bootstrap and virtual disk driver both
implement at UDP stack.
• Q: Why do I not get an option to choose what NIC to use
for PVS traffic in W2K8R2?
• Changes to the TCP stack in Windows 2008R2 mean that
the user no longer has access to or control over network
traffic paths within the OS. These options are no longer
available to the user space in Windows.
• So how is network traffic apportioned in W2K8R2?
• Windows decides on the best path based on available
network connections at that moment
• http://ccsweb02.citrite.net/q4/qmldap.dll
• “PVS Basic comprehensive training"