How do I enable LVE in LiteSpeed?

In LiteSpeed admin interface, do:

  Configuration -> Server -> Edit -> "Enable LVE" = "Yes" -> Save

How do I convert Linode CentOS 5.x VPS to CloudLinux

Start with this guide to prepare for custom CentOS kernel:
http://library.linode.com/linode-platform/custom-instances/pv-grub-howto#sph_centos-5
After that use standard way to convert from CentOS to CloudLinux:
http://www.cloudlinux.com/downloads/
Once you are done, in the Linode Manager, edit your Linode's configuration profile to use pv-grub-x86_64 (or 32bit one if you use 32bit arch) as the "Kernel". Make sure the root device is specified as xvda. Save your changes by clicking "Save Profile" at the bottom of the page, and reboot your Linode from the "Dashboard" tab.

How do I configure CloudLinux kernel on pv xen?

1. In /etc/sysconfig/kernel should be following lines:
UPDATEDEFAULT=yes
DEFAULTKERNEL=kernel-xen
If file does not exist, you should create it.
2. Run #yum install kernel-xen
3. Run #ln -s /boot/grub/grub.conf /boot/grub/menu.lst; ln -s /boot/grub/grub.conf /etc/grub.conf
If /boot/grub/grub.conf does not exist, create it using template in step 5, and repeat step 3
4. Run #rpm -qa|grep kernel
You should remove all kernel except xen kernel. For example, if output looks like this:
kernel-2.6.18-338.5.1.el5.lve0.8.25
kernel-xen-2.6.18-374.3.1.el5.lve0.8.44
kernel-headers-2.6.18-374.3.1.el5.lve0.8.44
then you should run: #rpm -e kernel-2.6.18-338.5.1.el5.lve0.8.25
5. Make sure your /etc/grub.conf looks like this:
default=0
timeout=10
title CloudLinux Server (2.6.18-374.3.1.el5.lve0.8.44xen)
root (hd0,0)
kernel /boot/vmlinuz-2.6.18-374.3.1.el5.lve0.8.44xen console=xvc0 root=/dev/sda1 ro
initrd /boot/initrd-2.6.18-374.3.1.el5.lve0.8.44xen.img
6. Switch to pygrub mode, and reboot the server
If you don't know how to switch in pygrub mode, contact your service provider,  as they should be able to do it for you.
bootloader = '/usr/bin/pygrub'