When you create an instant-clone desktop pool, you can configure certain options. You can use this worksheet to record your configuration options before you create the pool.

Before creating an instant-clone desktop pool, take a snapshot of the golden image. You must shut down the golden image in vCenter Server before taking the snapshot.

Table 1. Worksheet: Configuration Options for Creating an Instant-Clone Desktop Pool
Option Description
User assignment Select Floating or Dedicated.

In a floating instant-clone desktop pool, users are assigned random desktops from the pool. When a user logs out, the instant clone desktop VM is deleted. A new clone is then regenerated using the latest golden image, based on the pool provisioning setting.

In a dedicated instant-clone desktop pools, users are assigned a particular remote desktop and return to the same desktop at each login. When a user logs out, a refresh operation retains the computer name and the Mac address of the VM, deletes the desktop clone, and regenerates a new desktop clone from the latest golden image with the retained computer name and Mac address. You can optionally configure the instant-clone desktop pool to not refresh after log off.

Enable automatic assignment In a dedicated-assignment pool, a machine is assigned to a user when the user first logs in to the pool. You can also explicitly assign machines to users.

If you do not enable automatic assignment, you must explicitly assign a machine to each user. For more information, see Assign a Machine to a User in a Dedicated-Assignment Pool.

Enable Multi-User Assignment In a dedicated-assignment pool, you can assign multiple users to each machine in the pool.

Multi-user assignment is not supported for automatic user assignment.

If an assigned user has a connected or disconnected session on a multi-user assignment machine, other assigned users will be unable to launch a session on that machine. For more information, see Assign a Machine to a User in a Dedicated-Assignment Pool.

vCenter Server Select Instant clones and select the vCenter Server that manages the instant-clone VMs.
Desktop Pool ID The unique name that identifies the pool.

If you have multiple Connection Server configurations, make sure that another Connection Server configuration does not use the same pool ID. A Connection Server configuration can consist of a single Connection Server or multiple Connection Servers

Display name The pool name that users see when they log in from a client. If you do not specify a name, the pool ID is used.
Access group Select an access group for the pool or leave the pool in the default root access group.

If you use an access group, you can delegate managing the pool to an administrator who has a specific role.

Note: Access groups are different from vCenter Server folders that store desktop VMs. You select a vCenter Server folder later in the wizard.
State
  • Enabled. After being created, the pool is enabled and ready for immediate use.
  • Disabled. After being created, the pool is disabled and not available for use, and provisioning is stopped for the pool. Select this setting if you want other forms of baseline maintenance.
Connection Server restrictions
  • None. The desktop pool can be accessed by any Connection Server instance.
  • With tags. Select one or more Connection Server tags to make the desktop pool accessible only to Connection Server instances that have those tags. You can use the check boxes to select multiple tags.
You can restrict access to the pool to certain Connection Servers by clicking Browse and selecting one or more Connection Servers.

If you intend to provide access to desktops through VMware Workspace ONE Access, and you configure Connection Server restrictions, the VMware Workspace ONE Access app might display desktops to users when those desktops are actually restricted. VMware Workspace ONE Access users will be unable to launch these desktops.

Category Folder Specifies the name of the category folder that contains a Start menu shortcut for the desktop pool entitlement on Windows client devices. For more information, see Configuring Start Menu Shortcuts for Desktop and Application Pools in Setting Up Published Desktops and Applications in Horizon.
Client Restrictions Select whether to restrict access to entitled desktop pools from certain client computers. You must add the names of the computers that are allowed to access the desktop pool in an Active Directory security group. You can select this security group when you add users or groups to the desktop pool entitlement.
Session Types You can enable the VM Hosted Applications feature by selecting the supported session type for the desktop pool:
  • Desktop. Select this option to use the pool as a regular desktop pool. All the virtual machines in the pool can only be used to host desktops.
  • Application. Select this option to use all the virtual machines in the pool to host applications.
  • Desktop and Application. When this option is selected, the virtual machine in the pool can either host a regular desktop session or host an application session. The first connection to the particular virtual machine will determine the session type of the virtual machine.

For more information about the VM Hosted Applications feature, see the technical marketing white paper "Best Practices for Published Applications and Desktops in VMware Horizon and VMware Horizon Apps" available at https://techzone.vmware.com.

Automatically logoff after disconnect
  • Immediately. Users are logged off when they disconnect.
  • Never. Users are never logged off.
  • After. The time after which users are logged off when they disconnect. Type the duration in minutes.

    The logoff time applies to future disconnections. If a desktop session is already disconnected when you set a logoff time, the logoff duration for that user starts when you set the logoff time, not when the session was originally disconnected. For example, if you set this value to 5 minutes, and a session was disconnected 10 minutes earlier, Horizon will log off that session 5 minutes after you set the value.

Empty session timeout (applications only)

Determines the amount of time that an empty application session is kept open. An application session is empty when all the applications that run in the session are closed. While the session is open, users can open applications faster. You can save system resources if you disconnect or log off empty application sessions. Select Never, Immediate, or set the number of minutes as the timeout value. The default is After 1 minute. If you select Immediate, the session logs off or disconnects within 30 seconds.

You can further reduce the time the session logs off or disconnects by editing a registry key on the RDS Host on which Horizon Agent is installed. Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\VMware, Inc.\VMware VDM\Plugins\wssm\applaunchmgr\Params and set a value for WindowCheckInterval. The default value is 20000. This means that the poll for the empty session check is every 20 seconds, which sets the maximum time between the last application session close and session log off to 40 seconds. You can change this value to 2500. This means that the poll for the empty session check is every 2.5 seconds, which sets the maximum time between the last application close and session log off to 5 seconds.

Pre-launch session timeout (applications only) Determines the timeout for the application session before the session is disconnected or logged off.
When timeout occurs Determines whether an empty application session is disconnected or logged off after the Empty session timeout limit is reached. Select Disconnect or Log off. A session that is logged off frees up resources, but opening an application takes longer. The default is Disconnect.
Allow users to reset/restart their machines

Specify whether users can reset the virtual machine or restart the virtual desktop.

A reset operation resets the virtual machine without a graceful operating system restart.

A restart operation restarts the virtual machine with a graceful operating system restart.

Refresh OS disk after logoff Select whether and when to refresh the OS disks. This option is available for dedicated assignment pools.
  • Always. The OS disk is refreshed every time the user logs off. Select this option to use App Volumes with dedicated instant clones.
  • Every. The OS disk is refreshed at regular intervals of a specified number of days. Enter the number of days.

    The number of days is counted from the last refresh, or from the initial provisioning if no refresh has occurred yet. For example, if the specified value is 3 days, and three days have passed since the last refresh, the desktop is refreshed after the user logs off.

  • At. The OS disk is refreshed when its current size reaches a specified percentage of its maximum allowable size. The maximum size of a instant clone's OS disk is the size of the replica's OS disk. Enter the percentage at which refresh operations occur.
  • Never. The OS disk is never refreshed.
Reclaim VM disk space Determine whether to allow ESXi hosts to reclaim unused disk space on instant clones that are created in space-efficient disk format. The space reclamation feature reduces the total storage space required for instant clone desktops.
Note: This setting is only applicable if you use a vSphere version earlier than 6.7 and if you use non-vSAN storage. For vSphere 6.7 and later, space reclamation is done automatically by vSphere and no additional steps are needed on Horizon.
Initiate reclamation when unused space on VM exceeds: Type the minimum amount of unused disk space, in gigabytes, that must accumulate on a instant clone OS disk to trigger space reclamation. When the unused disk space exceeds this threshold, Horizon initiates the operation that directs the ESXi host to reclaim space on the OS disk.

This value is measured per virtual machine. The unused disk space must exceed the specified threshold on an individual virtual machine before Horizon starts the space reclamation process on that machine.

The default value is 1 GB.

Note: This setting is only applicable if you use a vSphere version earlier than 6.7 and if you use non-vSAN storage. For vSphere 6.7 and later, space reclamation is done automatically by vSphere and no additional steps are needed on Horizon.
Display Assigned Machine Name Displays the host name of the assigned machine instead of the desktop pool display name when you log in to Horizon Client.

If no machine is assigned to the user, then Display Name (No Machine Assigned) appears for the desktop pool when you log in to Horizon Client.

Allow user to initiate separate sessions from different client devices With this option selected, a user connecting to the same desktop pool from different client devices gets different desktop sessions. The user can only reconnect to an existing session from the same client device. When this setting is not selected, users are always reconnected to their existing session no matter which client device is used.
Default display protocol Select the default display protocol. The choices are Microsoft RDP, PCoIP, and VMware Blast.
Allow users to choose protocol Specify whether users can choose display protocols other than the default.
  • Yes. Allow users to choose a display protocol.
  • No. Do not allow users to choose a display protocol.
3D Renderer This field shows the type of 3D Render available for the instant-clone pool. This is not a selectable field. Depending on what you configured on the ESXi host and the golden image used for this pool, Horizon will automatically display one of the following two options:
  • NVIDIA GRID vGPU. 3D rendering is enabled for NVIDIA GRID vGPU.
  • Manage using vSphere Client. The 3D Renderer option that you configured in vSphere Client.
See Configuring 3D Rendering Options for Instant-Clone Pools.
Allow Session Collaboration Select Enabled to allow users of the desktop pool to invite other users to join their remote desktop sessions. Session owners and session collaborators must use the VMware Blast protocol.
Enable Provisioning You can enable or disable virtual machine provisioning in the desktop pool. When you disable provisioning in the desktop pool, Horizon stops provisioning new virtual machines for the desktop pool. After you disable provisioning, you can enable provisioning again.

Before you change a desktop pool's configuration, you can disable provisioning to ensure that no new machines are created with the old configuration. You can also disable provisioning to prevent Horizon from using additional storage when a pool is close to filling up the available space.

When you first create a desktop pool and disable this option, Horizon creates a desktop pool without any virtual machines. If you edit a desktop pool and disable provisioning, Horizon does not allow any new virtual machines to be provisioned in this desktop pool. End users can still connect to existing virtual machines.

For instant-clone desktop pools that are configured to refresh after a user logs out, Horizon deletes the old clone and creates a new clone to replace. This operation will continue to work even if you have disabled pool provisioning.

Stop provisioning on error Specify whether Horizon stops provisioning desktop VMs if an error occurs and prevents the error from affecting multiple VMs.
Naming pattern Specify a pattern that Horizon uses as a prefix in all the desktop VM names, followed by a unique number. The naming pattern can be used for both floating and dedicated-assignment pools. See Using a Naming Pattern for Desktop Pools.
Note: Naming machines manually is not supported for instant-clones.
Max number of machines Specify the total number of desktop VMs in the pool.

Provision machines on demand

Min number of machines

Provision all machines up front

Specify whether to provision all desktop VMs when the pool is created or to provision the VMs when they are needed.
  • Provision all machines up front. When the pool is created, Horizon provisions the number of VMs you specify in Max number of machines. For a floating instant-clone desktop pool, the MAC address is preserved on a resync or refresh.
  • Provision machines on demand. When the pool is created, Horizon creates the number of VMs based on the Min number of machines value or the Number of spare (powered on) machines value, whichever is higher. Additional VMs are created to maintain this minimum number of available VMs as more users connect to desktops. This provides dynamic pool expansion capability where the size of the pool expands and contracts to accommodate the number of users who need desktops. When Horizon is deployed on VMware Cloud on AWS, you can configure the Elastic DRS feature (rapid scaling) so that additional hosts can be automatically created (and conversely decommissioned) to meet the capacity required by the desktop pool. For more information about VMware Cloud on AWS, see the VMware Cloud on AWS documentation at https://docs.vmware.com/en/VMware-Cloud-on-AWS/index.html.
Desktop pool sizing Specify the maximum number of desktop VMs and powered on spare machines in the pool. For details, see Naming Machines Manually or Providing a Naming Pattern in Horizon Console.
Number of spare (powered on) machines Specify the number of desktop VMs to keep available to users.
Select separate datastores for replica and OS disks Specify whether to store the replica and OS disks on a datastore that is different from the datastores that the instant clones are on.

If you select this option, you can select the options to select one or more instant-clone datastores or replica disk datastores.

Parent VM in vCenter Select the golden image in vCenter Server for the pool.
Snapshot (default image) Select the snapshot you took of the golden image.

To specify the number of monitors and resolution for your instant-clone desktop pool, you must configure these parameters in the golden image and then take a snapshot. See Configure Number of Monitors and Screen Resolution.

VM folder location Select the folder in vCenter Server for the desktop VMs.
Cluster Select the vCenter Server cluster for the desktop VMs.
Resource pool Select the vCenter Server resource pool for the desktop VMs.
Datastores Select one or more datastores for the desktop VMs.

The Select Instant Clone Datastores window provides high-level guidelines for estimating the pool's storage requirements. These guidelines help you determine which datastores are large enough to store the clones. The Storage Overcommit value is always set to Unbounded and is not configurable.

Note: Instant clones and Storage vMotion are compatible. When you create an instant-clone desktop pool on a Storage DRS datastore, the Storage DRS cluster does not appear in the list of datastores. However, you can select individual Storage DRS datastores.
Networks

Select the networks to use for the instant-clone desktop pool. You can select multiple vLAN networks to create a larger instant-clone desktop pool. This option uses the network type from the current golden image configured in vSphere Client and displays networks based on the network type of the parent VM: DVS, NSX-t, and Standard. You can use the same network as the parent VM or select a network from the list of available options. Networks are filtered based on the parent VM network type available in the selected cluster.

The Select Networks wizard provides a list of networks based on the parent VM network type available in the selected cluster. To use multiple networks, you must unselect Use network from current parent VM image and then select the networks to use with the instant-clone pool. The Show All Networks switch shows or hides (greys out) incompatible networks within the selected network type. By default, only compatible networks are shown.

The wizard displays error messages for the following incompatible networks:

  • vmcNetworks. This network belongs to VMC internal network
  • dvsUplinkPort. Cannot use network because it does not meet the naming standards for a virtual switch uplink port.
  • notConfiguredOnAllHosts. Cannot use network because it is not configured on all hosts in the cluster.

The wizard does not list the Standard network type for selection. Therefore, if the parent VM network type is Standard, then you must select Use network from current parent VM image.

The wizard also provides the list of ports and port bindings that are available to use: static (early binding) and ephemeral. Instant-clones only support static port group types and ephemeral port group types are grayed out and listed as incompatible.

All selected NSX-t network segments must be the same size, such as all /24 networks. Unequal sized segments can result in provisioning errors.

vGPU Profile The vGPU profile for the pool is the vGPU profile of the snapshot you selected. The pool inherits this profile. You cannot select or edit this field in Horizon Console. For details, see Configuring 3D Rendering Options for Instant-Clone Pools.
Domain Select an Active Directory domain. The drop-down list shows the domains that you specify when you configure instant-clone domain administrators.
AD container Specify the Active Directory container's relative distinguished name.

For example: CN=Computers

In the Add Desktop Pool window, you can browse the Active Directory tree for the container. You can also copy, paste, or enter the path for the AD tree for the container.
Allow reuse of pre-existing computer accounts Select this option to use existing computer accounts in Active Directory when the virtual machine names of new instant clones match the existing computer account names. See Allow Reuse of Existing Computer Accounts.
Power-off script Specify the path name of a script to run on the desktop VMs and the script parameters before the VMs are powered off.
Post-synchronization script Specify the path name of a script to run on the desktop VMs and the script parameters after the VMs are created.