Installing XenServer Tools
XenServer Tools provide high performance I/O services without the overhead of traditional device emulation. XenServer Tools consists of I/O drivers (also known as Paravirtualized drivers or PV drivers) and the Management Agent.
The I/O drivers contain storage and network drivers, and low-level management interfaces. These drivers replace the emulated devices and provide high-speed transport between Windows and the XenServer product family software. During the installation of a Windows operating system, XenServer uses traditional device emulation to present a standard IDE controller and a standard network card to the VM. This allows Windows to complete its installation using built-in drivers, but with reduced performance due to the overhead inherent in emulation of the controller drivers.
The Management Agent , also known as the Guest Agent, is responsible for high-level virtual machine management features and provides full functionality to XenCenter, including quiesced snapshots.
XenServer has a simple mechanism to install and update the I/O drivers and the Management Agent. The I/O drivers and the Management Agent are combined together and issued as ‘XenServer Tools’ for ease of installation. See the following sections for information about installing XenServer Tools and updating the I/O drivers and the Management Agent.
Customers should install XenServer Tools on each VM to be able to perform the following operations:
- Cleanly shut down, reboot, or suspend a VM
- View VM performance data in XenCenter
- Migrate a running VM (using XenMotion or Storage XenMotion)
- Create quiesced snapshots or snapshots with memory (checkpoints), or revert to snapshots
- Adjust the number of vCPUs on a running Linux VM (Windows VMs require a reboot for this to take effect)
Running a VM without installing the XenServer Tools is not a supported configuration. While a Windows VM can function without them, performance is significantly hampered when the I/O drivers (PV drivers) are not installed. Running Windows VMs without these drivers is not supported. Some features, such as live relocation across physical hosts, will only work with the I/O drivers installed and active
Finding out the virtualization state of a VM
XenCenter reports the virtualization state of a VM on the VM’s General tab. You can find out whether or not XenServer Tools (I/O drivers and the Management Agent) are installed, and whether the VM has the capability to install and receive updates from Windows Update. The following section lists the messages displayed in XenCenter:
I/O optimized (not optimized) - displays whether or not the I/O drivers are installed on the VM. Click on the Install I/O drivers and Management Agent link to install the I/O drivers from the XenServer Tools ISO.
I/O drivers will be automatically installed on a Windows VM that has the ability to receive updates from Windows Update. For more information, see Updating XenServer Tools.
Management Agent installed (not installed) - displays whether or not the Management Agent is currently installed on the VM. Click on the Install I/O drivers and Management Agent link to install the Management Agent from the XenServer Tools ISO.
Able to (Not able to) receive updates from Windows Update - specifies whether the VM has the capability to receive I/O drivers from Windows Update. For more information, see Updating XenServer Tools.
Install I/O drivers and Management Agent - This message is displayed when the VM does not have the I/O drivers or the Management Agent installed. Click the link to install XenServer Tools. For Linux VMs, clicking the status link switches to the VM’s console and loads the XenServer Tools ISO. You can then mount the ISO and manually run the installation, as described in the following section.
If you have a large number of VMs on your server or a pool, select the server or pool on the Resources pane and click the Search tab. From the Saved Searches list, select VMs without XenServer Tools Installed. This displays a list of VMs that do not have XenServer Tools installed.
Installing XenServer Tools on Windows VMs
Note that installing XenServer Tools will cause any media in the virtual machine’s CD/DVD-drive to be ejected. Do not attempt to install XenServer Tools if the virtual machine’s CD/DVD-drive is in use, for example, during OS install from CD.
Select the VM in the Resources pane, right-click, and then click Install XenServer Tools on the shortcut menu. Alternatively, on the VM menu, click Install XenServer Tools.
On the General tab of the VM, click Install I/O drivers and Management Agent.
When you install XenServer Tools on your VM, you will be installing both I/O drivers (PV drivers) and the Management Agent.
- If AutoPlay is enabled for the VM’s CD/DVD drive, installation will start automatically after a few moments. The process installs the I/O drivers and the Management Agent. Restart the VM when prompted to get your VM to an optimized state.
If AutoPlay is not enabled, the XenServer Tools installer displays the installation options. Click Install XenServer Tools to continue with the installation. This mounts the XenServer Tools ISO (guest-tools.iso) on the VM’s CD/DVD drive.
When prompted, select to choose what happens with the XenServer Tools ISO.
Click Run Setup.exe to begin XenServer Tools installation. This opens the Citrix XenServer Windows Management Agent Setup wizard. Follow the instructions on the wizard to get your VM to an optimized state and perform any actions that are required to complete the installation process.
When you install XenServer Tools using this method, the Management Agent will be configured to get updates automatically. However, the I/O drivers will not be updated by the Management Agent update mechanism. This is the default behavior. If you prefer to change the default behavior, follow the instructions below in step b.
Alternatively, click Open folders to view files and then run Setup.exe from the CD drive. This option opens the Citrix XenServer Windows Management Agent Setup wizard and lets you customize the XenServer Tools installation and the Management Agent update settings.
Follow the instructions on the wizard to accept the license agreement and choose a destination folder. Customize your settings on the Installation and Updates Settings page. The Citrix XenServer Windows Management Agent Setup wizard displays the following settings by default. The wizard:
- Installs the I/O drivers
- Allows automatic updating of the Management Agent
- Does not allow the Management Agent to update the I/O drivers automatically.
If you do not want to allow the automatic updating of the Management Agent, select Disallow automatic management agent updates. If you prefer to update the I/O drivers automatically by the Management Agent, select Allow automatic I/O driver updates by the management agent. If you have chosen to receive I/O driver updates through the Windows Update mechanism, we recommend that you do not allow the Management Agent to update the I/O drivers automatically .
Click Install to begin the installation process. When prompted, perform any actions that are required to complete the XenServer Tools installation process and click Finish to exit the setup wizard.
- If you prefer to install the I/O drivers and the Management Agent on a large number of Windows VMs, install managementagentx86.msi or managementagentx64.msi using your preferred MSI installation tool. These files can be found on the XenServer Tools ISO.
- I/O drivers will be automatically installed on a Windows VM that has the ability to receive updates from Windows Update. However, we recommend that you install the XenServer Tools package to install the Management Agent, and to maintain supported configuration.
Installing XenServer Tools on Linux VMs
- Select the VM in the Resources pane, right-click, and then click Install XenServer Tools on the shortcut menu. Alternatively, on the VM menu, click Install XenServer Tools.
- Click Install XenServer Tools on the message dialog to go to the VM’s console.
As the root user, mount the image into the VM:
mount -o ro,exec /dev/disk/by-label/XenServer\\x20Tools /mnt <!--NeedCopy-->
If mounting the image fails, you can locate the image by running the command
blkid -t LABEL="XenServer Tools" <!--NeedCopy-->
Execute the installation script as the root user:
Unmount the image from the guest by running the command:
umount /mnt <!--NeedCopy-->
- If the kernel has been upgraded, or the VM was upgraded from a previous version, reboot the VM now.
Note that CD-ROM drives and ISOs attached to Linux VMs appear as /dev/xvdd (or /dev/sdd in Ubuntu 10.10 and later), rather than /dev/cdrom . This is because they are not true CD-ROM devices, but normal devices. When the CD is ejected by XenCenter, it hot-unplugs the device from the VM and the device disappears. This is different from Windows VMs, where the CD remains in the VM in an empty state
Updating XenServer Tools
XenServer has a simpler mechanism to automatically update I/O drivers (PV drivers) and the Management Agent for Windows VMs. This enables customers to install updates as they become available, without having to wait for a hotfix.
The Virtualization state section on a VM’s General tab specifies whether or not the VM is able to receive updates from Windows Update. The mechanism to receive I/O driver updates from Windows Update is turned on by default. If you do not want to receive I/O driver updates from Windows Update, you should disable Windows Update on your VM, or specify a group policy.
Ensure that all requested VM restarts are completed as part of the update. Multiple restarts might be required. If all requested restarts are not completed, this might result in unexpected behavior.
Updating the I/O drivers
If you are running newly created Windows VMs on XenServer 7.0 or higher, you will be able to get updates to I/O drivers automatically from Microsoft Windows Update, provided:
- You are running XenServer with Enterprise Edition, or have access to XenServer through Citrix Virtual Apps and Desktops entitlement
- You have created a Windows VM using XenCenter issued with XenServer 7.0 or higher
- Windows Update is enabled within the VM
- You have access to the internet, or are able to connect to a WSUS proxy server
Customers can also receive I/O driver updates automatically through the automatic Management Agent update mechanism. See Updating the Management Agent for details.
Updating the Management Agent
XenServer enables you to automatically update the Management Agent on both new and existing Windows VMs. By default, XenServer allows the automatic updating of the Management Agent. However, it does not allow the Management Agent to update the I/O drivers automatically. You can customize the Management Agent update settings during XenServer Tools installation. See Installing XenServer Tools on Windows VMs for details. The automatic updating of the Management Agent occurs seamlessly, and does not reboot your VM. In scenarios where a VM reboot is required, XenCenter issues notification to users about the required action.
To update the Management Agent automatically:
- You must be running XenServer 7.0 or higher with Enterprise Edition, or have access to XenServer through Citrix Virtual Apps and Desktops entitlement.
- You must have installed XenServer Tools issued with XenServer 7.0 or higher
- The Windows VM must be connected to the internet
- The ability to receive I/O drivers from Windows Update and the automatic updating of the Management Agent features are available for XenServer Enterprise Edition customers, or those who have access to XenServer through their Citrix Virtual Apps and Desktops entitlement.
- Updates to XenServer Tools can also be issued through the standard XenServer update (hotfix) mechanism. Such hotfixes contain updates to both I/O drivers and the Management Agent. There is no licensing restriction to update XenServer Tools issued as a hotfix.