12.3. Explanation of Settings and Controls in the New Pool and Edit Pool Windows
12.3.1. New Pool and Edit Pool General Settings Explained
The following table details the information required on the General tab of the New Pool and Edit Pool windows that are specific to virtual machine pools. All other settings are identical to those in the New Virtual Machine window.
| Field Name | Description |
|---|---|
| Template |
The template and template sub-version on which the virtual machine pool is based. If you create a pool based on the |
| Description | A meaningful description of the virtual machine pool. |
| Comment | A field for adding plain text human-readable comments regarding the virtual machine pool. |
| Prestarted VMs |
Allows you to specify the number of virtual machines in the virtual machine pool that will be started before they are taken and kept in that state to be taken by users. The value of this field must be between |
| Number of VMs/Increase number of VMs in pool by |
Allows you to specify the number of virtual machines to be created and made available in the virtual machine pool. In the edit window it allows you to increase the number of virtual machines in the virtual machine pool by the specified number. By default, the maximum number of virtual machines you can create in a pool is 1000. This value can be configured using the |
| Maximum number of VMs per user |
Allows you to specify the maximum number of virtual machines a single user can take from the virtual machine pool at any one time. The value of this field must be between |
| Delete Protection | Allows you to prevent the virtual machines in the pool from being deleted. |
12.3.2. New Pool and Edit Pool Type Settings Explained
The following table details the information required on the Type tab of the New Pool and Edit Pool windows.
| Field Name | Description |
|---|---|
| Pool Type | This drop-down menu allows you to specify the type of the virtual machine pool. The following options are available:
|
| Stateful Pool | Specify whether the state of virtual machines in the pool is preserved when a virtual machine is passed to a different user. This means that changes made by a previous user will persist on the virtual machine. |
12.3.3. New Pool and Edit Pool Console Settings Explained
The following table details the information required on the Console tab of the New Pool or Edit Pool window that is specific to virtual machine pools. All other settings are identical to those in the New Virtual Machine and Edit Virtual Machine windows.
| Field Name | Description |
|---|---|
| Override SPICE proxy | Select this check box to enable overriding the SPICE proxy defined in global configuration. This feature is useful in a case where the user (who is, for example, connecting via the VM Portal) is outside of the network where the hosts reside. |
| Overridden SPICE proxy address | The proxy by which the SPICE client connects to virtual machines. This proxy overrides both the global SPICE proxy defined for the Red Hat Virtualization environment and the SPICE proxy defined for the cluster to which the virtual machine pool belongs, if any. The address must be in the following format: protocol://host:port |
12.3.4. Virtual Machine Pool Host Settings Explained
The following table details the options available on the Host tab of the New Pool and Edit Pool windows.
| Field Name | Sub-element | Description |
|---|---|---|
| Start Running On | Defines the preferred host on which the virtual machine is to run. Select either:
| |
| Migration Options | Migration mode | Defines options to run and migrate the virtual machine. If the options here are not used, the virtual machine will run or migrate according to its cluster’s policy.
|
| Use custom migration policy | Defines the migration convergence policy. If the check box is left unselected, the host determines the policy.
| |
| Use custom migration downtime |
This check box allows you to specify the maximum number of milliseconds the virtual machine can be down during live migration. Configure different maximum downtimes for each virtual machine according to its workload and SLA requirements. Enter | |
| Auto Converge migrations | Only activated with Legacy migration policy. Allows you to set whether auto-convergence is used during live migration of the virtual machine. Large virtual machines with high workloads can dirty memory more quickly than the transfer rate achieved during live migration, and prevent the migration from converging. Auto-convergence capabilities in QEMU allow you to force convergence of virtual machine migrations. QEMU automatically detects a lack of convergence and triggers a throttle-down of the vCPUs on the virtual machine. Auto-convergence is disabled globally by default.
| |
| Enable migration compression | Only activated with Legacy migration policy. The option allows you to set whether migration compression is used during live migration of the virtual machine. This feature uses Xor Binary Zero Run-Length-Encoding to reduce virtual machine downtime and total live migration time for virtual machines running memory write-intensive workloads or for any application with a sparse memory update pattern. Migration compression is disabled globally by default.
| |
| Pass-Through Host CPU | This check box allows virtual machines to take advantage of the features of the physical CPU of the host on which they are situated. | |
| Configure NUMA | NUMA Node Count |
The number of virtual NUMA nodes to assign to the virtual machine. If the Tune Mode is Preferred, this value must be set to |
| Tune Mode | The method used to allocate memory.
| |
| NUMA Pinning | Opens the NUMA Topology window. This window shows the host’s total CPUs, memory, and NUMA nodes, and the virtual machine’s virtual NUMA nodes. Pin virtual NUMA nodes to host NUMA nodes by clicking and dragging each vNUMA from the box on the right to a NUMA node on the left. |
12.3.5. New Pool and Edit Pool Resource Allocation Settings Explained
The following table details the information required on the Resource Allocation tab of the New Pool and Edit Pool windows that are specific to virtual machine pools. All other settings are identical to those in the New Virtual Machine window. See Virtual Machine Resource Allocation Settings Explained in the Virtual Machine Management Guide for more information.
| Field Name | Sub-element | Description |
|---|---|---|
| Disk Allocation | Auto select target | Select this check box to automatically select the storage domain that has the most free space. The Target and Disk Profile fields are disabled. |
| Format | This field is read-only and always displays QCOW2 unless the storage domain type is OpenStack Volume (Cinder), in which case the format is Raw. |
