Creating A Guest System

These instructions set up a simple Fedora installation as a Xen guest system.

Building a Fedora Guest System

With Fedora Core 5, installation of Xen guests using anaconda is supported, although with a few known bugs. The xen package includes a script for starting guest installs. You can run it with

• # /usr/sbin/xenguest-install.py
  

You will then be prompted to answer a few questions regarding the virtual machine you are trying to create. ⁴

1. What is the name of your virtual machine? This is the label used for display in the various xm commands as well as being used as the name of the domain config file in /etc/xen

2. How much RAM should be allocated (in megabytes)? This is the amount of RAM to be allocated for the guest instance in megabytes (eg, 256). Note that installation with less than 256 megabytes is not recommended (or likely to work with test2).

3. What would you like to use as the disk (path)? The local path and file name of the file to serve as the disk image for the guest (eg, /home/joe/xenbox1). This will be exported as a full disk to your guest.

4. How large would you like the disk to be (in gigabytes)? The size of the virtual disk for your guest if the file specified above does not already exist. The amount to specify depends on what you intend to install. 4.0 gigabytes is a reasonable guess for a "default" install

5. What is the install location? This is the path to a Fedora Core 5 installation tree in the format used by anaconda. NFS, FTP, and HTTP locations are all supported. Examples include:

   • nfs:my.nfs.server.com:/path/to/test2/tree/

   • https://my.http.server.com/path/to/tree/

   • ftp://my.ftp.server.com/path/to/tree

If you get an error at this point saying 'The privileged domain did not balloon!', you may need to resize one or more of your existing VMs' memory limits in order to free up RAM for the new guest VM. For instance, to resize dom0 to use only 256 megs of RAM, you could run:

• xm mem-set 0 256
  

Once you've shrunk your existing domains, you should be able to re-try the xenguest-instally.py script.

After this, the install kernel and initrd will be grabbed from your install tree and the installer will start.

• Once the questions are answered, you should be prompted with the standard anaconda text screen to choose the installation language and then keyboard.

• Configure TCP/IP as you normally would for a system.

• You are now about to install the guest. You can proceed with either a text mode or graphical mode via VNC.

Graphical Mode Installation via VNC

• Select Start VNC

• Now provide a password for a secure VNC connection or No Password for an open connection

• The VNC server information will be presented. Connect with your choice of VNC client (either running on the local machine or another system).

• VNC will display a standard Fedora graphical installation screen. Proceed with the installation of your xen guest.

• Notes

  • The xvda device is the file identified during the install-script.py process. It appears to the guest as an entire disk, not just as a partition; you can partition it or carve it up with LVM just like a normal disk. The first time you use it, you will need to partition and format it during the install process.