3.3. Installing Guest Agents and Drivers

3.3.1. Red Hat Virtualization Guest Agents and Drivers

The Red Hat Virtualization guest agents and drivers provide additional information and functionality for Red Hat Enterprise Linux and Windows virtual machines. Key features include the ability to monitor resource usage and gracefully shut down or reboot virtual machines from the User Portal and Administration Portal. Install the Red Hat Virtualization guest agents and drivers on each virtual machine on which this functionality is to be available.

Table 3.1. Red Hat Virtualization Guest Drivers

Driver
Description
Works on
virtio-net
Paravirtualized network driver provides enhanced performance over emulated devices like rtl.
Server and Desktop.
virtio-block
Paravirtualized HDD driver offers increased I/O performance over emulated devices like IDE by optimizing the coordination and communication between the guest and the hypervisor. The driver complements the software implementation of the virtio-device used by the host to play the role of a hardware device.
Server and Desktop.
virtio-scsi
Paravirtualized iSCSI HDD driver offers similar functionality to the virtio-block device, with some additional enhancements. In particular, this driver supports adding hundreds of devices, and names devices using the standard SCSI device naming scheme.
Server and Desktop.
virtio-serial
Virtio-serial provides support for multiple serial ports. The improved performance is used for fast communication between the guest and the host that avoids network complications. This fast communication is required for the guest agents and for other features such as clipboard copy-paste between the guest and the host and logging.
Server and Desktop.
virtio-balloon
Virtio-balloon is used to control the amount of memory a guest actually accesses. It offers improved memory over-commitment. The balloon drivers are installed for future compatibility but not used by default in Red Hat Virtualization.
Server and Desktop.
qxl
A paravirtualized display driver reduces CPU usage on the host and provides better performance through reduced network bandwidth on most workloads.
Server and Desktop.

Table 3.2. Red Hat Virtualization Guest Agents and Tools

Guest agent/tool
Description
Works on
rhevm-guest-agent-common
Allows the Red Hat Virtualization Manager to receive guest internal events and information such as IP address and installed applications. Also allows the Manager to execute specific commands, such as shut down or reboot, on a guest.
On Red Hat Enterprise Linux 6 and higher guests, the rhevm-guest-agent-common installs tuned on your virtual machine and configures it to use an optimized, virtualized-guest profile.
Server and Desktop.
spice-agent
The SPICE agent supports multiple monitors and is responsible for client-mouse-mode support to provide a better user experience and improved responsiveness than the QEMU emulation. Cursor capture is not needed in client-mouse-mode. The SPICE agent reduces bandwidth usage when used over a wide area network by reducing the display level, including color depth, disabling wallpaper, font smoothing, and animation. The SPICE agent enables clipboard support allowing cut and paste operations for both text and images between client and guest, and automatic guest display setting according to client-side settings. On Windows guests, the SPICE agent consists of vdservice and vdagent.
Server and Desktop.
rhev-sso
An agent that enables users to automatically log in to their virtual machines based on the credentials used to access the Red Hat Virtualization Manager.
Desktop.
rhev-usb
A component that contains drivers and services for Legacy USB support (version 3.0 and earlier) on guests. It is needed for accessing a USB device that is plugged into the client machine. RHEV-USB Client is needed on the client side.

Important

The Legacy USB option has been deprecated and will be removed in Red Hat Virtualization 4.1.
Desktop.

3.3.2. Installing the Guest Agents and Drivers on Windows

The Red Hat Virtualization guest agents and drivers are installed on Windows virtual machines using the rhev-tools-setup.iso ISO file, which is provided by the rhev-guest-tools-iso package installed as a dependency to the Red Hat Virtualization Manager. This ISO file is located in /usr/share/rhev-guest-tools-iso/rhev-tools-setup.iso on the system on which the Red Hat Virtualization Manager is installed.

Note

The rhev-tools-setup.iso ISO file is automatically copied to the default ISO storage domain, if any, when you run engine-setup, or must be manually uploaded to an ISO storage domain.

Note

Updated versions of the rhev-tools-setup.iso ISO file must be manually attached to running Windows virtual machines to install updated versions of the tools and drivers. If the APT service is enabled on virtual machines, the updated ISO files will be automatically attached.

Note

If you install the guest agents and drivers from the command line or as part of a deployment tool such as Windows Deployment Services, you can append the options ISSILENTMODE and ISNOREBOOT to RHEV-toolsSetup.exe to silently install the guest agents and drivers and prevent the machine on which they have been installed from rebooting immediately after installation. The machine can then be rebooted later once the deployment process is complete. 
D:\RHEV-toolsSetup.exe ISSILENTMODE ISNOREBOOT

Procedure 3.4. Installing the Guest Agents and Drivers on Windows

  1. Log in to the virtual machine.
  2. Select the CD Drive containing the rhev-tools-setup.iso file.
  3. Double-click RHEV-toolsSetup.
  4. Click Next at the welcome screen.
  5. Follow the prompts on the RHEV-Tools InstallShield Wizard window. Ensure all check boxes in the list of components are selected.
    Selecting All Components of Red Hat Virtualization Tools for Installation

    Figure 3.2. Selecting All Components of Red Hat Virtualization Tools for Installation

  6. Once installation is complete, select Yes, I want to restart my computer now and click Finish to apply the changes.
The guest agents and drivers now pass usage information to the Red Hat Virtualization Manager and allow you to access USB devices, single sign-on into virtual machines and other functionality. The Red Hat Virtualization guest agent runs as a service called RHEV Agent that you can configure using the rhev-agent configuration file located in C:\Program Files\Redhat\RHEV\Drivers\Agent.

3.3.3. Automating Guest Additions on Windows Guests with Red Hat Virtualization Application Provisioning Tool(APT)

Red Hat Virtualization Application Provisioning Tool (APT) is a Windows service that can be installed on Windows virtual machines and templates. When the APT service is installed and running on a virtual machine, attached ISO files are automatically scanned. When the service recognizes a valid Red Hat Virtualization guest tools ISO, and no other guest tools are installed, the APT service installs the guest tools. If guest tools are already installed, and the ISO image contains newer versions of the tools, the service performs an automatic upgrade. This procedure assumes you have attached the rhev-tools-setup.iso ISO file to the virtual machine.

Procedure 3.5. Installing the APT Service on Windows

  1. Log in to the virtual machine.
  2. Select the CD Drive containing the rhev-tools-setup.iso file.
  3. Double-click RHEV-Application Provisioning Tool.
  4. Click Yes in the User Account Control window.
  5. Once installation is complete, ensure the Start RHEV-apt Service check box is selected in the RHEV-Application Provisioning Tool InstallShield Wizard window, and click Finish to apply the changes.
Once the APT service has successfully installed or upgraded the guest tools on a virtual machine, the virtual machine is automatically rebooted; this happens without confirmation from the user logged in to the machine. The APT Service will also perform these operations when a virtual machine created from a template that has the APT Service already installed is booted for the first time.

Note

The RHEV-apt service can be stopped immediately after install by clearing the Start RHEV-apt Service check box. You can stop, start, or restart the service at any time using the Services window.