• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 1105
  • Last Modified:

1.XD 5.6 - How does the XenDesktop Controller Create Machines in vCenter

I just deployed XenDesktop 5.6 FP1 on VSphere 5 and Vcenter .

I created my first catalog to have 2 machines (Pooled Random) ..While was was watching Vcenter doing the stuff, i though of posting a question on how it does the stuff in simple terms:

Using MCS

My golden Image computer Win 7 x64 Enterprise was On and it started to snapshot and then delete somethings and then 2 mahines were created.

Can some one explain me simply what happens : Steps XD controller takes , vCenter takes

Do i have to keep the gold Image On.

Why do the newly created machines stay in off state after being created.

When will they be turned on.

I know i may find all info online , but while i search that i though of asking the experts as you people always give precise advice that helps me get upto the speed.
2 Solutions
TunerMLSystems EngineerCommented:
Let me try and advise you as much as possible, though it would be good for you to do the XenDesktop Overview (SPO) free course offered by Citrix, since your obviously diving in without any experience.

Firstly for XenDesktop to communicate with vShpere SSL certificates must be in place.

The template with which you deploy your MCS machines is consumed and no longer visible as a VM or template on the hypervisor, though you will still see the alloted storage space for the virtual disk, which is now being used by XenDesktop.

After adding computers to a catalog (the amount is specified by yourself at the time of catalog creation) you must the create a Desktop Group, here you assign users and configure the power options for the quantity of machines to be started, what times of the day, and any necessary peak power options you may want to set.
MOQINFRAAuthor Commented:
Hi TurnerML

I have created the Catalog and all is fine. What i am not understanding how the stuff is done in the background.

I need to understand How the image is used , Is it cloned /Snapshot for catalog creation etc

When i started to created my another Catalog , i still see the Golden image

But now i see an entry under it while creating the catalog

I havent templated the golden image , it is just a machine which i left powered on and can still see in vCenter and during catalog creation.
The golden image VM hangs around.  You'll use it to update the VMs created from it.  You don't have to keep this VM on except when you perform an update to the base image.

When you configured XD you specified a host (vSphere) along with a service account that the XD Controller(s) use to communicate with vSphere.  XD uses the service account to log on to vCenter and then leverages the hypervisor APIs to create, start up, shutdown, and reboot VMs.

Power state is controlled by the properties of the desktop group (assignment).  Have you created one of these yet?  When you create a desktop group XD will assign a default power state setting, which *should* power on some of the VMs.  You can and should change the power state settings to ensure you have enough idle VMs on for your users.
Network Scalability - Handle Complex Environments

Monitor your entire network from a single platform. Free 30 Day Trial Now!

FYI, this is NOT my work but easier than me writing this all out myself. http://blogs.citrix.com/2011/06/28/machine-creation-services-primer-part-1/

1 . Manual Step: First, have your master virtual machine created. This means you need to define the VM (vCPU, RAM, Disk space), install the OS, install the apps and make any configurations you want to be part of your user’s desktops. If you are thin provisioning the disk, you only use the amount needed up to your maximum amount define.
2. Manual Step: Within Desktop Studio, you create a catalog for a pooled desktop and you have to select the master virtual machine you want to base other VMs on. This is the one you installed and configured with the OS and applications.
3. Automatic Step: MCS creates a snapshot (thin) of the master VM unless you selected a snapshot, which will not create another snapshot. This uses minimal space
4. Automatic Step: MCS creates a full copy of the point in time snapshot and places this on each storage repository defined in the host connection. This will utilize the amount of space used for your complete image.
5. Automatic Step: MCS adds these desktops into Active Directory. This step creates the unique AD identities to be used later in the process
6. Automatic Step: MCS creates the number of VMs specified in the create catalog wizard with two disks defined for each VM. However, in addition to the 2 disks for each VM, a master will also be be stored in the same storage repository. If you have multiple storage repositories defined, then each one will get the following types of disks
      1.The full snapshot, which is read-only and shared across the VMs just created. Each storage repository will get one. This is the same disk identified in step 4.
      2. A unique identity disk (16MB) used to provide each VM with a unique identity. Functionality within the XenDesktop Controllers creates the identity disks. Each VM gets an identity disk.
      3. A unique difference disk used to store any writes made to the VM. The disk is thin provisioned (if supported by the storage) and will increase to the maximum size of the base VM if required. Each VM gets a difference disk.
I would also add that if you considering a few hundred or more virtual desktops, I would advise using provisioning services over MCS.
MOQINFRAAuthor Commented:
Thank you ,
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Featured Post

Ultimate Tool Kit for Technology Solution Provider

Broken down into practical pointers and step-by-step instructions, the IT Service Excellence Tool Kit delivers expert advice for technology solution providers. Get your free copy now.

Tackle projects and never again get stuck behind a technical roadblock.
Join Now