Installation guide

Reb o o t t o lo ad t h e n ew kern el
Reboot the system. The computer will restart with the default kernel. The KVM module should
be automatically loaded with the kernel. Verify KVM is running:
$ lsmod | grep kvm
kvm_intel 85992 1
kvm 222368 2 ksm,kvm_intel
The kvm module and either the kvm_intel module or the kvm_amd module are present if
everything worked.
33.2.2. KVM t o Xen
The following procedure covers changing from the KVM hypervisor to the Xen hypervisor. This
procedure assumes the kvm package is installed and enabled.
1. ⁠
Inst all th e Xen p ackag es
Install the kernel-xen and xen package if you have not already done so.
# yum install kernel-xen xen
The kernel-xen package may be installed but disabled.
2. ⁠
Verif y wh ich kern el is in u se
Use the uname command to determine which kernel is running.
$ uname -r
2.6.18-159.el5
The present kernel, "2.6.18-159.el5", is running on the system. This is the default kernel.
If the kernel has xen on the end (for example, 2.6.18-159.el5xen) then the Xen kernel is
running and you can skip the substep.
a. ⁠
Ch an g in g t h e d ef au lt kern el t o t h e Xen kern el
The grub.conf file determines which kernel is booted. To change the default kernel
edit the /boot/grub/grub.conf file as shown below.
default=0
timeout=5
splashimage=(hd0,0)/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux Server (2.6.18-159.el5)
root (hd0,0)
kernel /vmlinuz-2.6.18-159.el5 ro root=/dev/VolGroup00/LogVol00
rhgb quiet
initrd /initrd-2.6.18-159.el5.img
title Red Hat Enterprise Linux Server (2.6.18-159.el5xen)
root (hd0,0)
⁠Chapt er 33. T ips and t ricks
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