2. Machine Creation Services (MCS)
Citrix XenDesktop 5

3. Jits Langedijk Sr. Consultant Application & Desktop Delivery
@JRLangedijk
JitsLangedijk

4. Agenda Citrix XenDesktop 5.x Why MCS? Where can I “find” MCS?
What does MCS do exactly?
How does MCS work?
What is IntelliCache?
What about PVS?

5. Citrix XenDesktop 5 (december 2010)
Farm
Desktop Group
DDC / Broker / Controller
IMA datastore
Terminal Services
Site
Catalog with Desktop Group
XenDesktop Controller
SQL database
Removed Dependency

6. XenDesktop 5.5 (August 2011) Second Generation Flash Redirection
Windows Media Redirection
Multi-Stream ICA (UDP for audio)
MS RemoteFX Support
Windows 7 Aero Redirection
HDX 3D Pro
HDX Plug-N-Play
Desktop Director 2.0

7. XenDesktop 5.6 (march 2012) Personal vDisk (RingCube)
SCCM 2012 support
Virtual Desktop Agent ( )
Desktop Director 2.1

8. Why MCS? Single image management Less complex infrastructure
Easy to deploy
Citrix IntelliCache

9. Where can I find MCS?
MCS is integrated in to XenDesktop 5.0 >

10. MCS based Virtual Desktops
Desktop Machine Types
Pooled
Dedicated
Existing
Physical
Streamed
MCS based Virtual Desktops
Direct copies of the master VM. Changes are not persisted. (Random / Static)
Permanently assigned to individual users. Changes are persisted.
VM’s that were previously created.
Desktops hosted on dedicated blade servers
vDisk imaged from a master target device with PVS

11. New Desktop Machine Types XD 5.6
Pooled with personal vDisk
Streamed with personal vDisk
Personal vDisk session
15:30 hr

12. MCS Desktop Machine Types XD 5.6
Pooled (Stateless)
Random – Users are randomly assigned a machine at logon
Static – Users are assigned the same machine at logon
Dedicated (Stateful)
Pooled with personal vDisk (next session)

13. Create Catalog with MCS
Type
Machine Type
Master Image
VMs
Number of VMs
Accounts
Create accounts
Admini
stration
Administration
Summary

14. Create Catalog with MCS
Create machine accounts
Create a proviosiong scheme by copying master VM
Create machines using the provisioning scheme
Add machines to the broker catalog

15. What does MCS do exactly?
Admin selects “Golden Master Image”, this is copied as Full Clone and becomes the “Golden Master VM Image”
Hypervisor 1 2 3 4
Admin Provisions ‘x’ VM’s
MCS creates an ID Disk and a Difference Disk and attaches them to each VM
Storage
MCS Powers up the VM, obtains Identity from the ID Disk ID ID ID ID
DIFF
DIFF
DIFF
DIFF
OS Reads come from the Base
Golden Master VM Image (BASE)
Golden Master Image
OS Writes go to the Diff Disk

16. What does MCS do exectly?
Each VM consists of three “parts”
1 – Master VM
2 – Difference Disk (diff disk)
3 – Identidy Disk (ID disk)

17. The ID Disk The Identidy disk 16 MB in size
Contains the “Identidy” of the virtual machine
A file called ‘CTXSOSID.INI’, The ListOfDDCs key
Attached as a second disk to the VM at creation
Remains untouched for the lifetime of the VM

18. The Diff Disk The Difference disk
The “primary” disk for the provisioned machine
Created by making a difference disk to the master image
Destroyed at VM boot (Pooled)
Persistent at VM Boot (Dedicated)

19. Citrix XenDesktop 5.6 “Small Overview”
Desktop Studio
Desktop Director
XenDesktop Controller
Machine Creation
Service
Host Service
AD Identity Service
Machine Identity Service
Broker Service
Configuration
Service
Virtual Desktop Agent
Machine Creation
Services
Broker
Services
Infrastructure
Services
SQL Server

20. Machine Creation Services consists of…
Responsible for the creation of the VMs
AD Identity Service
Creates / Manages AD computer accounts and passwords of VM.
Machine Identity Service
Create DIFF and ID disks for VMs
Manages storage attached to provisioned VMs
Machine Identity Agent (VDA based)
Component that resides on the VDA that ensures VDA Identity within the domain
Maintains the computer AD password of the Virtual Desktop
Machine Creation Service
Responsible for the creation of the VMs
Uses AD Identity Service and Machine Identity Service to create Provisioned Machines.
Maintenance of the master image that is used to provide the desktops.
AD Identity Service
Creates / Manages AD computer accounts and passwords to provide the identity for Provisioned Machines.
AD computer accounts get created by the AD Identity Service
Existing AD computer accounts can be imported.
Machine Identity Service
Create OS and Identity disks for VMs (provision)
Remove OS and Identity disks for VMs (deprovision)
Manages storage attached to provisioned VMs
Ensures a fresh Diff disk is attached to the VM at boot
Ensures the ID Disk is attached to the VM at boot time (used by the Machine Identity Service Client to provide the Computer Account)
Update of OS disk (reset VM functionality)
Machine Identity Agent
Component that resides on the VDA
Ensures VDA Identity within the domain
Maintains the computer AD password of the Virtual Desktop
There is no direct communication between the Machine Creation Services and the Machine Identity Agent
The Machine Identity Service provides the information required by the Machine Identity Agent via files on the Identity disk
These files are created by the Machine Identity Service at machine provisioning time and mounted against the appropriate VM.

21. Machine Creation Process
Provisioning process consists of 2 mechanisms
Creation of a Provisioning Scheme
Creation of Machines
The Provisioning Scheme defines
Name, CPU Count, Memory size, Master Image VM, Identity Pool, Hosting Unit, Boot Behaviour
Tasks on the Provisioning Scheme are synchronous
i.e. you cannot provision and delete at the same time

22. B B A B A B A B A A B A B B A B A B A A B A B B A A B A B
Snapshot chain is consolidated for performance into new Golden Master VM Image
Master VM
Desktop Group is updated to reference new Golden Master VM Image
snapshot 3 B
snapshot 2
consolidate
snapshot 1
New “image” is propagated to Virtual Machines at reboot
golden image

23. IntelliCache XenDesktop NFS Based Storage
Master Image created through XenDesktop MCS
VM is configured to use Master Image
VM using Master Image is started
XenServer creates read cache object on local storage
Reads in VM being done from local cache
Additional Reads done from SAN when required
Writes will happen in VHD child per VM
Local “write” cache is deleted when VM is shutdown/restarted
Additional VMs will use same read cache VM VM
011001 VM
XenServer
Cache – not local copy
Fast update master images
Live migration
Persistent/Assigned VMs
Seamless fallback to shared storage
Master Image
Cache
NFS Based Storage

24. Provisioning Services
What about PVS?
Provisioning Services:
Hypervisor(s)
Provisioning Services
Storage
Caches ‘base image’ in RAM for fast delivery
Machine Creation Service:
Hypervisor(s)
Storage
RAM Cache
Caches ‘base image’ in RAM for fast delivery

25. What about IOPS? XenDesktop MCS produces about 1.5x more IOPS than PVS
1100 Desktops on XS
MCS
PVS
Total IOPS
18,000
11,000
Read:Write IOPS ratio
50:50
10:90
Average IOPS per desktop 16 10
Stated by Citrix!!

26. Summary Citrix XenDesktop 5.6 Why MCS? Where can I “find” MCS?
What does MCS do exactly?
How does MCS work
IntelliCache

27. Thanks for your patience!