Install the Scale Computing Guest Agent Tools (Virtual Disk Drivers)

The Scale Computing Guest Agent Tools are a series of dedicated VirtIO drivers — a standard for virtualization, network, and disk device drivers — available within SC//HyperCore™ HyperVisor for guest operating system performance and compatibility. The SC//HyperCore system runs on a Red Hat Enterprise Linux operating system with a KVM Linux kernel; the Scale Computing Guest Agent Tools help a guest VM recognize that it is running inside a Red Hat-based hypervisor and allow information from inside the guest to be passed back to the host and the web interface.

A lightweight guest agent tool can be deployed on SC//HyperCore VMs to coordinate application data consistency for VM-level snapshots. The guest agent quiesces I/O at the time of the snapshot when possible so that all open applications will not have to roll back incomplete transactions.

You may receive alerts that there was a ‘quiesce failure’ for a VM snapshot. Snapshots will still be taken and be viable even if the quiesce fails; they will simply be crash consistent rather than application consistent.

The Scale Computing Guest Agent Tools also enable: disk mount information displayed on VM cards, live disk add/deletion/cloning features on supported OSes, recognition and support of VM virtual disks and NICs, and many other features. It is always recommended to keep the latest drivers installed.

See Supported Guest Operating Systems for the list of tested Windows and Linux/Unix guest OSes, their minimum required SC//HyperCore version, and VirtIO driver versions.

Obtaining and Updating the Scale Computing Guest Agent Tools

The Scale Computing Guest Agent Tools are not available as a separate external download. They are packaged with the SC//HyperCore system itself, and the correct version for your cluster’s firmware is delivered as an ISO through the SC//HyperCore web interface.

To ensure a VM has the latest Scale Computing Guest Agent Tools:

  1. Update the cluster to the most recent SC//HyperCore General Availability release.
  2. Eject all versions of the Scale Computing Guest Agent Tools from all VM cards.
  3. Open the Media tab and delete all existing versions of the Scale Computing Guest Agent Tools listed there.
  4. Create a new VM with the OS type set to Windows. Creating a new Windows VM automatically adds the latest Scale Computing Guest Agent Tools ISO (matched to the cluster’s current firmware) to the Media tab, where it can be mounted to any existing VM.

If the cluster is already on the latest release and creating a new VM does not populate a newer Scale Computing Guest Agent Tools version than what you currently have, contact Scale Computing Support. See Contacting Scale Computing Support.

When to Run the Scale Computing Guest Agent Tools

Run or update the Scale Computing Guest Agent Tools on a VM if you encounter:

  • Issues with the guest OS utilizing underlying hardware
  • Drive expansion issues
  • Quiesce failures
  • Problems adding or removing virtual disks
  • General VM performance issues

Leaving the Scale Computing Guest Agent Tools ISO unmounted from a VM’s CD tray does not remove drivers that have already been installed in the guest OS.

Always take a snapshot of the VM before installing or updating the Scale Computing Guest Agent Tools, whether on Windows or Linux/Unix.

Windows

  1. Open the Devices screen on the VM card.
  2. Add the latest Scale Computing Guest Agent Tools drivers (provided with the SC//HyperCore software) into the virtual CD tray.
  3. Access the guest OS and the CD tray containing the Scale Computing Guest Agent Tools.
  4. Double-click the appropriate installer for the guest OS. Inside the Scale Computing Guest Agent Tools package there are two Windows Installer Packages: one for 32-bit systems (ending in x86) and one for 64-bit systems (ending in x64).
  5. When the Scale Computing Guest Agent Tools Setup Wizard appears, click Install.
  6. If a security confirmation window appears, verify the installation to proceed.
  7. When the installer finishes installing and/or updating all necessary VirtIO drivers, click Finish to close the wizard.

Installing the Scale Computing Guest Agent Tools should not require an OS reboot. If issues persist after installation, refresh the Scale Computing Guest Agent Tools using the steps in Obtaining and Updating the Scale Computing Guest Agent Tools.

Linux / Unix

  1. Access the guest OS.
  2. Install the qemu-guest-agent package (may also be called qemu-ga) using the appropriate command for your OS (typically yum install or apt-get).
  3. Start the qemu-guest-agent or qemu-ga service once it is installed.
  4. In some instances, an OS complete power cycle (power off and power back on, not a reboot) may be required to apply the changes.