It has been a year and half since VMware Instant Clone Technology became available in VMware Horizon 7. With each successive release, this capability has improved in quality and feature richness. If you are still on the older VMware View Composer linked-clone technology, it’s time to try a new way of provisioning desktops.
Provisioning using Instant Clone Technology is significantly faster than with View Composer linked-clone technology. In addition, instant cloning makes desktop and Remote Desktop Services (RDS) server patching a cinch. A clone is automatically deleted when the user logs out, and a new clone is created using the latest master image.
This rolling update approach can reduce the maintenance window to near zero. And best of all, there’s no more refresh, recompose and rebalance—and no more View Composer server and database!
In this post, I’d like to provide some tips for you, current Horizon 7 admins, to quickly get Instant Clone Technology up and running. If you already have Horizon 7 installed and configured, complete the following tasks to start creating instant clones. For more details, please refer to the product documentation.
- Horizon 7 is already installed and configured in your environment.
- You need a Horizon Enterprise license.
- You also need VMware vSphere 6.0 Update 1 or later.
- Instant Clone Technology requires static port binding with fixed port allocation. Also, your VMware vCenter and VMware ESXi versions must be the same. The combination of vCenter 6.5 and ESXi 6.0 is not currently supported.
- Review the supported guest operating system (OS) versions:
- Verify that Change Block Tracking (CBT) is disabled on vCenter.
- Configure an Active Directory domain for instant clones. The instant-clone domain administrator must have certain Active Directory domain privileges. (Note: If you have multiple domain controllers spread across many sites, you may face this issue.)
- In Horizon Administrator, select View Configuration>Instant Clone Domain Admins.
- Click Add.
- Enter the login name and password for the instant-clone domain administrator.
- Ensure vCenter Server User configured for Horizon 7 has sufficient privileges on vCenter Server to create instant-clone desktops. If you have previously created successful View Composer linked clones, the vCenter Server User likely has sufficient privileges on vCenter for instant clones. For more information see the “View Composer and Instant Clone Privileges Required for the vCenter Server User” guide.
- Create and prepare a master virtual machine (VM) for instant cloning. Be sure to select VMware Horizon Instant Clone Agent rather than VMware Horizon View Composer Agent during Horizon Agent installation.
- It’s best to start with a fresh Windows machine with the latest updates.
- You must use the VMXNET3 network adapter. Using the default E1000 adapter can cause customization timeout errors during cloning.
- If you are using Windows 7 Service Pack 1 (SP1), you may run into this Microsoft issue. Follow the Knowledge Base article to install this Microsoft hotfix.
- Make sure that the virtual machine hardware is version 11 or later.
- Follow steps to prepare a master image and optimize it for Horizon deployment. For more information see “Creating and Preparing a Virtual Machine for Cloning.”
- Starting with Horizon 7.2, Super Video Graphics Array (SVGA) settings (e.g. number of monitors, max resolution) for an instant clone pool are inherited from the values configured in the master image. This Knowledge Base article provides information on how to configure the SVGA settings in the master image. By default, vCenter configures one monitor and a max resolution of 1280×800 in the master VM. However, this value may change with different versions of vCenter or even different versions of an OS, so it is always best practice to configure these settings yourself. Prior to Horizon 7.2, the SVGA settings for the instant clone pools were hardcoded to two monitors and a max resolution of 1600×1200. This cannot be changed. (Note: This is valid only for non-vGPU environments. In case of vGPU being enabled, SVGA settings—monitors and vRam size—are taken from vGPU graphics settings.)
- Finally, shut down the prepared master image and take a snapshot.
- Now you are ready to create your first instant clone virtual desktop infrastructure (VDI) pool. The Add Desktop Pool Wizard guides you through the steps. (Note: If the internal parent VM triggers a memory usage alert in vCenter, you can ignore the alert because it is a false alert.)
- In Horizon Administrator, select Catalog> Desktop Pools.
- Click Add.
- Select Automated Desktop Pool.
- Select either Dedicated or Floating User Assignment.
- On the vCenter Server page, select Instant Clones.
- Follow the prompts to create the pool.
- Instant-clone desktops cannot have persistent disks. Users can use network share or VMware App Volumes to store persistent user data.
- VMware Virtual Volumes and vSphere Storage APIs for Array Integration (VAAI) native Network File System (NFS) snapshots are not supported. They do not provide significant value for instant clones.
- Microsoft’s System Preparation (Sysprep) tool and VMware QuickPrep are not available for desktop customization. Use ClonePrep, which is specifically designed for instant clones.
- Windows 8 and Windows 8.1 are not supported.
- Internet Protocol version 6 (IPv6) is not supported.
- Persona Management is not available.
- You cannot specify a minimum number of ready (provisioned) machines during instant-clone maintenance operations. This feature is not needed because the high speed of creating instant clones means that some desktops are always available even during maintenance operations.
Learn more about instant-clone use cases, the Instant Clone Technology and its benefits in this whitepaper, “VMware Horizon 7 Instant-Clone Desktops and RDSH Servers.”