Red Hat Training

A Red Hat training course is available for Red Hat Satellite

Chapter 10. Virtualization

In order to manage and provision your client systems, you must first synchronize content from RHN's central servers to your Satellite.
RHN recommends that you sync at least the following channels:
For Red Hat Enterprise Linux 5:
  • Red Hat Enterprise Linux Server (v. 5 for 32-bit x86) — rhel-i386-server-5 (and all child channels)
  • Red Hat Network Tools for RHEL Server (v. 5 for 32-bit x86) — rhn-tools-rhel-i386-server-5
  • Red Hat Enterprise Linux Server Virtualization (v. 5 for 32-bit x86) — rhel-i386-server-vt-5 (and all child channels)
For Red Hat Enterprise Linux 6:
  • Red Hat Enterprise Linux Server (v. 6 for 64-bit x86_64) — rhel-x86_64-server-6 (and all child channels)
  • Red Hat Network Tools for RHEL Server (v. 6 for 64-bit x86_64) — rhn-tools-rhel-x86_64-server-6

10.1. Setting Up the Host System for Your Virtual Systems

Before creating guest systems, you must first prepare your host system. To do this, create a Red Hat Enterprise Linux 5 Server kickstart profile, then use that kickstart profile to install the operating system on your host. Once these steps are complete, you can proceed to provision virtual guests.

10.1.1. Create a Kickstart Profile for the Guest Systems

  1. Login to the Satellite's web interface. Navigate to the Kickstart Overview screen by clicking the Manage Kickstarts link in the Tasks widget in Your RHN, or by clicking on the Systems tab, followed by the Kickstart subtab in the left navigation bar.
  2. On the Kickstart Overview page, click the Create a New Kickstart Profile link in the Kickstart Actions widget in the upper right corner.
    1. Enter a label for your profile that will enable you to distinguish it from your other profiles. For the remaining instructions, we'll assume the label is host-system-for-virtual-guests.
    2. For the Base Channel field, select Red Hat Enterprise Linux (v.5 for $ARCH) (where $ARCH is the architecture of your host system).

      Note

      You may install 32-bit Red Hat Enterprise Linux 5 on a 64-bit host system. If you choose to do this, however, please be aware that your guest systems must also run the 32-bit version of Red Hat Enterprise Linux.
    3. In the Kickstartable Tree field, select ks-rhel-$ARCH-server-5 where $ARCH is the architecture of your host system.
    4. Please select Para-Virtualized Host for the Virtualization Type field.

      Note

      If you are changing the Virtualization Type of an existing kickstart profile, it may also modify the bootloader and partition options, potentially overwriting any user customizations. Be sure to review the Partitioning tab to verify these settings when changing the Virtualization Type.
    5. Click the Next button in the lower right of the screen to continue on to the next step.

      Note

      If any of the fields are missing the options indicated above, you may not have successfully synced software channel content to your Satellite from Red Hat's servers.
  4. Select the location of the distribution files for the installation of your host system. There should already be a Default Download Location filled out and selected for you on this screen. Click the Next button on this screen to continue to Step 3.

    Note

    If the default download location is missing, you may not have successfully synced software channel content to your Satellite from Red Hat's server.
  5. Choose a root password to set on the host system you will be provisioning, and click Finish to finish creation of the profile.
  6. You will be shown the newly-created kickstart profile. You may browse through the various tabs of the profile and modify the settings as you see fit, but this is not necessary as the default settings should work well for the majority of cases.
    In order to be able to remotely start and stop the guest using the Satellite web interface, you will need to include the package acpid.

10.1.2. Kickstart Your Host System

Next, kickstart your host system using your newly-created kickstart profile. There are three different scenarios for kickstarting your host system. Please read through these three scenarios below, and follow the instructions for the scenario that applies best to you:

10.1.2.1.  Your Host System Does Not have Red Hat Enterprise Linux Installed

Create a boot CD to initiate the kickstart on your host system. You will be able to use the kickstart profile we created in earlier steps to provision the host. Note you must have physical access to the machine you intend to use in order to follow these steps:
  1. You will find an ISO to create a boot CD for you host by using ssh to log into your Satellite. It is at the following location on your satellite: 
    /var/satellite/rhn/kickstart/ks-rhel-i386-server-5/images/boot.iso

    Note

    It is possible to use a flash-memory USB key to boot your system in order to kickstart it. Refer to the Red Hat Enterprise Linux System Administration Guide (available at http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/index.html) for tips on how to do this. Note that your host system's hardware must support boot via these devices.
  2. Insert the boot CD in the drive and reboot the system, making sure the CD-ROM drive is set as the primary boot device in the system's BIOS.
  3. After reboot, you should find yourself at a boot prompt. Type the following command at this prompt to start your kickstart: 
    linux \
ks=http://your-satellite.example.com/ks/label/the profile label you created earlier

    Note

    For some systems you may either need to add ksdevice=eth0 to the command above or disable one of two or more NICs in the system's BIOS to avoid confusion during the kickstart process.
  4. The kickstart for your host system should begin. It should take around fifteen minutes to complete. Upon successful completion of this kickstart, you will have provisioned a host system for your virtual guest and registered it to your Satellite.

10.1.2.2. Your Host System Has Red Hat Enterprise Linux 6 Installed

You should register your host system to your Satellite and check to see if the required kvm packages are installed on the system. If they are not, install them using the Satellite.

Note

On Red Hat Enterprise Linux 6, virtualization is only supported on 64-bit Intel and AMD machines.

Note

The xen virtualization host is not currently supported on Red Hat Enterprise Linux 6.
  1. Register your host system to your Satellite. Use ssh to connect to your host system. Register your host system to your satellite issuing the following command as root: 
    rhnreg_ks --serverUrl=http://your-satellite.example.com/XMLRPC \
--username=username --password=password

    Note

    If your host system is already registered to a different Red Hat Network server, add the --force to the command above.
  2. Next, open up the host system's profile in the Satellite web interface. Log into the web interface of your Satellite at https://your-satellite.example.com/. Click on the Systems tab in the top navigational bar. You should see the host system you just registered - click on its profile name to access its system profile page.
  3. Make sure your system has access to the software channels it needs to access the software required for hosting virtual guests. From your host system's profile page, click on the Alter Channel Subscriptions link on the profile page under the Subscribed Channels header. Check the RHEL Virtualization and Red Hat Network Tools for RHEL Server checkboxes and click the Change Subscriptions button underneath the list of channels.
  4. Next, check to see if you have the necessary software installed for hosting virtual guest on the system. On the host system, issue the following command as root: 
    rpm -q qemu-kvm rhn-virtualization-host python-virtinst
    If rpm indicates these packages are not installed, you must install them by running the following command as root on the system: 
    yum install qemu-kvm rhn-virtualization-host python-virtinst
  5. Restart the machine to pick up the changes, or use the appropriate modprobe command for your processor: 
    modprobe kvm_intel
    or: 
    modprobe kvm_amd
  6. You will also need to install and run the osad package in order for your host system to be responsive to commands sent from the Satellite, such as start, pause, resume, and shutdown. To install: 
    yum install -y osad
    After installation, you should then start the osad process: 
    /sbin/service osad restart
  7. Your host system should now be ready for RHN virtual guest provisioning.

10.1.3. Your Host System Has Red Hat Enterprise Linux 5 Installed

You should register your host system to your Satellite and check to see if the required xen or kvm packages are installed on the system. If they are not, install them using the Satellite.
  1. Register your host system to your Satellite. Use ssh to connect to your host system. Register your host system to your satellite issuing the following command as root: 
    rhnreg_ks --serverUrl=http://your-satellite.example.com/XMLRPC \
--username=username --password=password

    Note

    If your host system is already registered to a different Red Hat Network server, add the --force to the command above.
  2. Next, open up the host system's profile in the Satellite web interface. Log into the web interface of your Satellite at https://your-satellite.example.com/. Click on the Systems tab in the top navigational bar. You should see the host system you just registered - click on its profile name to access its system profile page.
  3. Make sure your system has access to the software channels it needs to access the software required for hosting virtual guests. From your host system's profile page, click on the Alter Channel Subscriptions link on the profile page under the Subscribed Channels header. Check the RHEL Virtualization and Red Hat Network Tools for RHEL Server checkboxes and click the Change Subscriptions button underneath the list of channels.
  4. Next, check to see if you have the necessary software installed for hosting virtual guest on the system. On the host system, issue the following command as root: 
    rpm -q xen kernel-xen rhn-virtualization-host
    For kvm, issue the following command as root: 
    rpm -q kvm kmod-kvm rhn-virtualization-host python-virtinst
    If rpm indicates these packages are not installed, you must install them by running the following command as root on the system: 
    yum install xen kernel-xen rhn-virtualization-host
    For kvm users, install by running the following command as root: 
    yum install kvm kmod-kvm rhn-virtualization-host python-virtinst
    For Xen, you will then need to edit the /etc/grub.conf configuration file to boot the new xen kernel by default. To do this, select the lines in grub.conf that pertain to the xen kernel from the beginning of the title line to the end of the initrd line, copy the lines, delete them, and paste them so they are the first kernel entry in grub.conf. Also ensure that the value of the default variable at the top of grub.conf is set to a value of '0'.

    Note

    If you ever update the kernel on the host system, the standard kernel is the default choice upon reboot. To ensure that the Xen kernel is chosen by default, change the following value in the /etc/sysconfig/kernel file: 
    DEFAULTKERNEL=kernel
    Change the value to kernel-xen: 
    DEFAULTKERNEL=kernel-xen
  5. Restart the machine to pick up the changes, or use the appropriate modprobe command for your processor: 
    modprobe kvm_intel
    or: 
    modprobe kvm_amd
  6. Reboot the system, boot it into the xen kernel. The system should not automatically boot into the xen kernel on reboot but if you would like to make sure it has for troubleshooting purposes, use the command uname -r to see if the running kernel is a xen kernel. If you do not see the xen string in the name of the kernel, you have not booted into the correct kernel.

    Note

    If the system already has xen and kernel-xen installed you do not need to reboot after installing rhn-virtualization-host.
  7. You will also need to install and run the osad package in order for your host system to be responsive to commands sent from the Satellite, such as start, pause, resume, and shutdown. To install: 
    yum install -y osad
    after installation, you should then start the osad process: 
    /sbin/service osad restart
  8. Your host system should now be ready for RHN virtual guest provisioning.