Seeing as it is now July 8th, I hope all in the USA enjoyed the 4th and that everyone – around the world – is having a great start to the weekend!

The inspiration and encouragement of this blog stems from several discussions, but one specifically with an individual – you know who you are! – regarding Scientific Linux and XenServer 6.2.  It was a rather interesting discussion that will be continued internally, but the focal point was Scientific Linux versus XenTools, etc for this RedHat/CentOS-based distro and how I have made it run (with tools) in the past/present.

More information regarding Scientific Linux can be found at https://www.scientificlinux.org/

I have personally used this distro in previous versions of XenServer and even have 5.x and 6.0 (Carbon) running at present within XenServer 6.2 (as well as Alpha).

With this being said, the question of “full support” might come to mind as it is not listed as an officially supported guest OS in our documentation.  So, the point of this blog is to discuss how one can install Scientific Linux and XenTools Guest Agent Additions for educational/test purposes until this OS is officially supported, etc.

The following document contains many screenshots gathered during my installation of Scientific Linux 5.x as well as 6.x and I hope it is of use to all.

The Template and Install Media

First decide which version of Scientific Linux you will be using: 5.x or 6.0.  The reason for this is that the choice will determine the installation media from https://www.scientificlinux.org/

The template you will want to use will be CentOS 5 or CentOS 6: more specifically, 32 or 64 bit depending on the final decision.  This decision will dictate source URL needed as to install Scientific Linux as a guest VM within XenServer.  So, after the example below – which points out the specific templates I just mentioned based on SL 5.x or 6.0 – the remainder of this blog will illustrate the installation (as well as) the XenTools installation process for either version:

Scientific Linux 5.x

Select the CentOS 5 64-bit template when creating a new VM and be sure to reference the following URL to install Scientific Linux 5.x as a guest VM:

http://ftp2.scientificlinux.org/linux/scientific/5x/x86_64/

As you walk through the VM/Guest creation wizard, the install media source will be asked of you.

Ensure you reference the URL (provided above) as opposed to a CDROM or ISO image:

After selecting NEXT and proceeding to specify your guest VM parameters, the installer should start just fine within XenCenter:

Looks familiar, eh?  It is at this point I would detail the remainder of the install, but I am not one to make suggestions on what software or how you should partition your own VM.  Once the installation is complete, you will be prompted to reboot:

After rebooting you will most likely be taken through First Boot steps: networking config, authentication, etc.  Once complete, login as root to this guest VM’s CLI and execute the following command before installing XenTools:

yum update

This will run for a few minutes and will require your attention, but after this process is complete execute the following command to continue:

reboot

After the guest VM has fully rebooted, mount the XenTools ISO from XenCenter:

Now, login as root to the guest VM’s command line and execute the following commands:

mkdir tools

mount -o loop /dev/xvdd tools/

(/dev/xvdd may be different for your virtual cd device)

cd tools/Linux

./install.sh

After running install.sh, you should be presented with a Yes/No question and upon selecting Yes, the following output should be quite familiar:

At the advice of the installer, reboot the guest VM one last time and after it fully boots you will now notice you have full capabilities to migrate, shutdown, pause, and reboot the Scientific Linux 5.x guest VM:

Presto!  While the steps for Scientific Linux 6.x are virtually the same, let’s visit the same steps with a different approach to installing the XenTools Guest Additions for Linux.

Scientific Linux 6.x

Select the CentOS 6 64-bit template when creating a new VM and be sure to reference the following URL to install Scientific Linux 6.x as a guest VM:

http://ftp.scientificlinux.org/linux/scientific/6.0/x86_64/os/

As you walk through the VM/Guest creation wizard, the install media source will be asked of you.

Ensure you reference the URL (provided above) as opposed to a CDROM or ISO image:

After selecting NEXT and proceeding to specify your guest VM parameters, the installer should start just fine within XenCenter:

Again, this looks familiar (sans color), right?  As for the rest of the operating system installer – due to most of it being hard-coded – partition your drive accordingly and make any changes necessary for your purposes.  Once completed, the installer will ask you to reboot:

After rebooting you will most likely be taken through First Boot steps: networking config, authentication, etc.  Once complete, login as root to this guest VM’s CLI and execute the following command before installing XenTools:

yum update

This will run for a few minutes and will require your attention, but after this process is complete execute the following command to continue:

reboot

After the guest VM has fully rebooted, mount the XenTools ISO from XenCenter:

Now, login as root to the guest VM’s command line and execute the following commands:

mkdir tools

mount -o loop /dev/xvdd tools/

(/dev/xvdd may be different for your virtual cd device)

cd tools/Linux

Here is where Scientific Linux 6.x is a bit different.  The XenTools Guest Additions for Linux will not recognize the release if you use install.sh:

This is in fact not a Fatal Error, but an error induced because the distro build and revision are not presented as expected.  This means that you will manually need to install the XenTools Guest Additions by executing the following commands and rebooting:

rpm -ivh xe-guest-utilities-xenstore-6.2.0-1137.x86_64.rpm

and

rpm -ivh xe-guest-utilities-6.2.0-1137.x86_64.rpm

then

reboot

Post reboot, once the Scientific Linux 6.x guest VM is completely running you will now notice you have full capabilities to migrate, shutdown, pause, and reboot the Scientific Linux 6.x guest VM:

And with that, I say:

This is from my virtual desktop to you!

–jkbs

@xenfomation

This blog post covers a product configuration or procedure which Citrix does not currently offer support for.  Use of this configuration should only be used in a lab or test environment and not with production deployments.  The author is actively seeking feedback on the potential of implementing support for this configuration, but the form any level of support takes has yet to be determined.