Storix Software SBAdmin Citrix XenServer Recovery Guide - Manual (Page 5)

Storix System Backup Administrator 5 Citrix XenServer Recovery Guide
Copyright © 2014 Storix, Inc.
Storix is a registered trademark of Storix, Inc in the USA. SBAdmin is a trademark of Storix, Inc in the USA and other countries
System Recovery of Citrix XenServer virtualized guests(domU)
The steps to perform system recovery of a Citrix XenServer virtual machine (domU) using SBAdmin are very
similar to the steps for any other Linux system. Refer to the
SBAdmin Linux System Recovery Guide for
additional details. However, the following considerations deserve mention because they are specific to Citrix
XenServer:
Determining virtualization type
Citrix XenServer is capable of doing both HVM and PV virtualization. HVM (hardware virtual machine)
technology is similar to a system running on real hardware. PV (paravirtualization) technology is a type of
virtualization specific to Xen. This type of virtualization requires the guest kernel to be modified to run in the
virtual machine.
The type of virtualization used is set at the time the virtual machine is created (please refer to Citrix
documentation for further information on creating new virtual machines). The profile used to create the
virtual machine will determine which type of virtualization is used. This is not immediately clear when using
the XenServer graphical interface.
The type of virtualization technolgy used by the domU, can be determined by logging into the XenServer
and running the following command.
#xe vm-list params=HVM-boot-policy,uuid,name-label
You will see output similar to the following:
uuid ( RO) : 8f7f2b5c-57d1-ff53-c4b5-d9b0a716cdd4
name-label ( RW) : Red Hat Enterprise Linux 5
HVM-boot-policy ( RW):
uuid ( RO) : 732588a6-f7e7-11f0-484a-d7c4100b19da
name-label ( RW) : Custom Linux
HVM-boot-policy ( RW) : BIOS order
The output indicates that the virtual machine named “Custom Linux” is using HVM because the HVM-boot-
policy is set to “BIOS order”. The machine named “Red hat Enterprise Linux 5” is using PV.
When restoring a backup to a new virtual machine (domU), the newly created virtual machine must use the
same type of virtualization as the system that was backed up.
Booting a paravirtualized domU
When booting a paravirtualized domU there are two boot loader options pygrub and eliloader. Pygrub is
used to boot from a harddisk device and eliloader is used to boot from a cdrom. When recovering a domU
that had been previously installed it may be necessary to change this option before booting the SBAdmin
boot media.
To determine which boot loader is in use, the following command may be run on the XenServer. Replacing
the uuid for the domU to be booted.
#xe vm-list params=PV-bootloader uuid=94012487-6bfa-306d-6e92387682eb9b0f