# Manage hosts (VDI) There are two basic types of hosts when using Parallels RAS VDI: template-based and non-template based. This topic describes management tasks for both host types, indicating whether a task applies to a particular host type. ## **Viewing host list** To view the list of non-template based hosts, select **Farm** > \ > **VDI** > **Desktops**. If you have a filter applied to the list, remove it by click the magnifying glass icon. Without the filter, the list shows all desktops available in this RAS Farm, including hosts (both template-based and non-template based), hosts from a pool (RAS or native), and pool-based Remote PCs. Therefore, the **Desktops** tab is a location where you can view all of your desktops in one place. Here you can perform all of the standard desktop management tasks accessible from the **Tasks** menu, including Recreate, Delete, Assign, Unassign, Start, Stop, Restart, Suspend, Reset, Show sessions, and others.The Restart operation (graceful) has a 10 min timeout. If not completed during this time, the Reset operation (forced) will be used. To view the list of hosts created from a template, select **Farm** > \ > **VDI** > **Templates.** Select a template and click **Tasks** > **Show hosts**. You will be switched to the **Desktops** tab where the list of desktops will be filtered to include only those that belong to the template. As was mentioned above, you can perform all of the standard desktop management operations on this tab, including power operations, which are described in detail later in this section. For the list to include only the hosts from a particular pool, select a pool in the **Pools** tab and click **Tasks** > **Show hosts in Pool**. The filter in the **Desktop** tab can also be applied manually by clicking the magnifying glass icon and entering the filter criteria in the fields that appear at the top of the list. ## **Site defaults** Hosts created from a template inherit the template settings. To view the settings, note on which template a host is based and then view properties of that template, specifically the **Settings** and **Security** tabs. For more information, see [**Site defaults**](/landing/ras-admin-guide/parallels-ras-21-administrators-guide/virtual-desktop-infrastructure-vdi/site-defaults-vdi.md). Note that you a template can inherit Site default settings or you can specify your own custom settings for it. Non-template based hosts have their own settings, some of which (specifically Settings and Security) are inherited from [Site defaults](/landing/ras-admin-guide/parallels-ras-21-administrators-guide/virtual-desktop-infrastructure-vdi/site-defaults-vdi.md). To see settings for a non template-based VM, navigate to **Farm** > \ > **VDI** > **Desktops**. A host that doesn't belong to a template is identified by an empty value in the **Template** column. Right-click a template and choose **Properties** (note that template-based hosts do not have this menu option). ## **Checking the RAS Guest Agent status** A host must have the RAS Guest Agent installed and the agent must match the Parallels RAS version. The agent is installed by default when a host is created from a template. If a host was created using the native hypervisor tools, it may not have the agent installed in it. In such a case, the host will be able to serve only the remote desktop. To enable it to server applications or documents, you'll need to install the agent yourself. To check if the RAS Guest Agent is installed in a host and is up to date: 1. Select a host in the list and then click **Tasks** > **Troubleshooting** > **Check agent**. 2. The **Guest Agent Information** dialog opens displaying the information about the RAS Guest Agent. 3. If the agent is not installed, click the **Install** button and follow the instructions. The agent will be push installed in Windows running inside the host. ## **Deleting a host** To delete a template-based host, select it and then click the **Tasks** > **Delete**. {% hint style="warning" %} **Important:** You should delete a host only from the RAS Console. You should not try to delete a host using the hypervisor's native client or web interface. If you do, it may delete not only the VM but its parent template as well (which will also invalidate all other hosts created as linked clones from this template). The reason for this is some native hypervisor clients treat linked clones as standalone VMs. Parallels RAS treats linked clones as clones, not as standalone VMs. {% endhint %} ## **Managing hosts that failed preparation** If a template-based host encounters a problem during the preparation stage, it remains on the server but cannot be used. You can identify such VMs by the "Failed to create" value in the **Status** column. Unless a VM like this is repaired, it will be automatically removed after the time period specified in the [Site defaults](/landing/ras-admin-guide/parallels-ras-21-administrators-guide/virtual-desktop-infrastructure-vdi/site-defaults-vdi.md). To see Site defaults: 1. Select **Farm** > \ > **VDI** > **Desktop** and then click **Tasks** > **Site defaults**. 2. In the dialog that opens, on the **General** tab, view or modify (if needed) the **Auto remove hosts which failed preparation after** option. You can set any of the available time periods by selecting it from the drop-down list or you can type a desired value, such as "8 days" or "12 hours". ## **Recreating a host** If something happens to a template-based host and it becomes unusable, you don't have to delete it and create a new one. Instead, you can recreate it keeping its name, MAC address, and other properties. This way none of the other Site settings, which may rely on a broken host, will be affected. Another reason for recreating a host is to apply changes made to the template (when you exit from maintenance without executing the Recreate command). Please note that recreated VMs can keep the the following properties: * MAC address is kept on ESXi, vCenter, Hyper-v, Hyper-v Failover Cluster, Nutanix AHV (AOS), and SC//HyperCore. * BIOS UUID is kept on ESXi and vCenter. * DRS groups are kept on vCenter. To recreate one or more hosts: 1. In the Parallels RAS Console, navigate to **Farm** > \ > **VDI** > **Templates**. 2. To recreate all deployed hosts, click the **Tasks** drop-down list and choose **Recreate all hosts**. 3. To recreate a specific host (or multiple hosts), click **Tasks** > **Show hosts**. This will open the **Desktops** tab, which will list hosts. Select one or more hosts and then click the **Tasks** > **Recreate**. When you recreate a host: * The procedure deletes a VM and creates a new one from the same template. * The new host retains the same computer name as the one it replaces. * If a host is running, all unsaved data in its memory will be lost. For this reason, an important data should be saved to an external storage. ## Assigning a host If a template-based host becomes unassigned from its host pool, the Parallels console shows a dialog indicating that a templated host is not assigned to a host pool at a particular site. To assign the host back to the host pool: 1. Open the hosts VDI hosts overview 2. Select one or more unassigned hosts 3. Right-click select **Assign to host pool** 4. Select the host pool you want to assign the host to and click **OK**. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.parallels.com/landing/ras-admin-guide/parallels-ras-21-administrators-guide/virtual-desktop-infrastructure-vdi/manage-vdi/manage-hosts-vdi.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.