20.2.3. Direct kernel boot

When installing a new guest virtual machine OS, it is often useful to boot directly from a kernel and initrd stored in the host physical machine OS, allowing command line arguments to be passed directly to the installer. This capability is usually available for both para and full virtualized guest virtual machines.

  ...
  <os>
    <type>hvm</type>
    <loader>/usr/lib/xen/boot/hvmloader</loader>
    <kernel>/root/f8-i386-vmlinuz</kernel>
    <initrd>/root/f8-i386-initrd</initrd>
    <cmdline>console=ttyS0 ks=http://example.com/f8-i386/os/</cmdline>
    <dtb>/root/ppc.dtb</dtb>
  </os>
  ...
  

Figure 20.4. Direct Kernel Boot

The components of this section of the domain XML are as follows:

Table 20.4. Direct kernel boot elements

ElementDescription
<type>same as described in the BIOS boot section
<loader>same as described in the BIOS boot section
<kernel>specifies the fully-qualified path to the kernel image in the host physical machine OS
<initrd>specifies the fully-qualified path to the (optional) ramdisk image in the host physical machine OS.
<cmdline>specifies arguments to be passed to the kernel (or installer) at boot time. This is often used to specify an alternate primary console (eg serial port), or the installation media source / kickstart file