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35.12. Xen configuration files

When you create guests with the virt-manager or virt-install tools on Red Hat Enterprise Linux 5, the guests configuration files are created automatically in the /etc/xen directory.


Red Hat advises users not to manually edit Xen configuration files. Xen configuration files have limited error checking and many unsupported variables. Editing Xen configuration files may damage your guests, make guests unbootable or cause data loss.
The example below is a typical a para-virtualized guest configuration file:
name = "rhel5vm01"
memory = "2048"
disk = ['tap:aio:/var/lib/libvirt/images/rhel5vm01.dsk,xvda,w',]
vif = ["type=ieomu, mac=00:16:3e:09:f0:12 bridge=xenbr0', 
"type=ieomu, mac=00:16:3e:09:f0:13 ]
vnc = 1
vncunused = 1
uuid = "302bd9ce-4f60-fc67-9e40-7a77d9b4e1ed"
bootloader = "/usr/bin/pygrub"
on_reboot = "restart"
on_crash = "restart"
Note that the serial="pty" is the default for the configuration file. This configuration file example is for a fully-virtualized guest:
name = "rhel5u5-86_64"
builder = "hvm"
memory = 500
disk = ['/var/lib/libvirt/images/rhel5u5-x86_64.dsk.hda,w']
vif = [ 'type=ioemu, mac=00:16:3e:09:f0:12, bridge=xenbr0', 'type=ieomu, mac=00:16:3e:09:f0:13, bridge=xenbr1']
uuid = "b10372f9-91d7-ao5f-12ff-372100c99af5'
device_model = "/usr/lib64/xen/bin/qemu-dm"
kernel = "/usr/lib/xen/boot/hvmloader/"
vnc = 1
vncunused = 1
apic = 1
acpi = 1
pae = 1
vcpus =1
serial ="pty" # enable serial console
on_boot = 'restart'


Editing Xen configuration files is unsupported. Use virsh dumpxml and virsh create (or virsh edit) to edit the libvirt configuration files (xml based) which have error checking and safety checks.