Xen 3.x Configuration File Options

== Xen Configuration File Options ==
Originial Document at http://www.xen.org/files/Support/XenConfigurationDetails.pdf
== SUMMARY ==
This file contains a complete summary of all the configuration options available in open source Xen. I
am using the Xen 3.4 source tree so some of these options may not be available in previous versions.
The complete list of options is viewable in the python source file create.py in
xen/tools/python/xen/xm/.
The file contains two types of configuration settings: options and variables.
== STANDARD CONFIGURATIONS ==
To assist the reader of the document, here are some sample configurations that are commonly used. A
complete list of examples can be found at /xen-3.4.0/tools/examples.
Example 1 (Comments in Italics)
(from http://www.linuxdevcenter.com/pub/a/linux/2006/01/26/xen.html)
Kernel image file
kernel = /boot/vmlinuz-2.6.11-1.1366_FC4xenU
Initial memory allocation (MB) for new domain
memory = 128
Name of domain (must be unique)
name = "dokeos.x-tend.be"
Additional configuration settings
extra = "selinux=0 3"
Network Interfaces
vif = ['ip = "10.0.11.13", bridge=xen-br0']
Disk devices domain has access to
disk = ['phy:vm_volumes/root.dokeos,sda1,w'
,'phy:vm_volumes/var.dokeos,sda3,w'
,'phy:vm_volumes/www.dokeos,sda4,w'
,'phy:vm_volumes/swap.dokeos,sda2,w'
]
Set root device
root = "/dev/sda1 ro"
Example 2 (Comments in Italics)
(Source xmexample1 from Xen source code)
Kernel image file
kernel = "/boot/vmlinuz-2.6.10-xenU"
Optional ramdisk
ramdisk = "/boot/initrd.gz"
Domain build function; default is linux
builder = "linux"
Initial memory allocation (MB) for new domain
memory = 64
Name of domain (must be unique)
name = "ExampleDomain"
128-bit UUID for the domain
uuid = "06ed00fe-1162-4fc4-b5d8-11993ee4a8b9"
List of which CPUs this domain is allowed to use; VCPU0 runs on CPU2 & VCPU1 runs on CPU3
cpus = ["2", "3"]
Number of virtual CPUs to use (default is 1)
vcpus = 2
Network interface created with defaults
vif = [ ]
Frame buffer device; default is no frame buffer; example below creates one using
the SDL backend''
vfb = [ 'sdl=1' ]
TPM instance the user domain should communicate
vtpm = [ 'instance=1,backend=0' ]
Root device for NFS
root = "/dev/nfs"
NFS server
nfs_server = '192.0.2.1'
Root directory on NFS server
nfs_root = '/full/path/to/root/directory'
Sets runlevel 4
extra = "4"
Domain exit behavior settings
on_poweroff = 'destroy'
on_reboot = 'restart'
on_crash = 'restart'
Configure PVSCSI devices
vscsi = [ '/dev/sdx, 0:0:0:0' ]
== OPTIONS ==
Help
;help: Print this help.
help or h (default = 0)
;help_config: Print the available configuration variables (vars) for the "configuration script
help_config (default = 0)
Misc
;quiet:Quiet.
quiet or q (default =0)
;path: Search path for configuration scripts
path (default='.:/etc/xen')
;defconfig: Use the given Python configuration script
defconfig or f (default='xmdefconfig')
;config: Domain configuration to use (SXP)
config or F (default=None)
;dryrun: Dry run — prints the configuration in SXP but does not create the domain
dryrun or n (defaut = 0)
;xmldryrun: Dry run — prints the configuration in XML but does not create the domain
xmldryrun or x (defaut = 0)
;skipdtd: Skip DTD checking - skips checks on XML before creating.
skipdtd or s (default = 0)
;paused: Leave the domain paused after it is created
paused or p (default = 0)
;vncviewer: Connect to the VNC display after the domain is created
vncviewer (default = 0)
;vncviewer-autopass: Pass VNC password to viewer via stdin and -autopass
vncviewer-autopass (default = 0)
;console_autoconnect: Connect to the console after the domain is created.
console_autoconnect or c (domain=0)
== VARIABLES ==
Kernel + Memory Size
;kernel: Path to the kernel image
kernel (Default=' '; Value='FILE')
;loader: Path to HVM firmware
loader (Default=' ' ;Value='FILE')
;features: Features to enable in guest kernel
features (Default=' ';Value='FEAUTRES')
;ramdisk: Path to ramdisk image (optional)
ramdisk="/data/guest1/initrd.img"
;builder: Function to use to build the domain
builder (Default='linux'; Value='FUNCTION')
;memory: Domain memory in MB
memory (Default=128; Value='MEMORY')
;maxmem: Maximum domain memory in MB
maxmem (Default=None; Value='MEMORY')
;boot: Default Boot Device
boot (Default='c';Value='a|b|c|d') 
;shadow_memory: Domain shadow memory in MB
shadow_memory (Default=0; Value='MEMORY)
;bootloader: Path to bootloader
bootloader (default=None; Value='File')
;bootargs: Arguments to pass to boot loader
bootargs (default=None; Value='Name')
;bootentry: DEPRECATED. Entry to boot via boot loader. Use bootargs.
bootentry (default=None; Value='Name')
;s3integrity: Should domain memory integrity be verified during S3? (0=protection is disabled; 1=protection is enabled.
s3integrity (Default=1; Value='TBOOT_MEMORY_PROTECT')
;machine_address_size: Maximum machine address size
machine_address_size (Default=None;Value='BITS')
;suppress_spurious_page_faults: Do not inject spurious page faults into this guest
suppress_spurious_page_faults (Default=None;Value='yes|no')
== CPU ==
;cpu: CPU to run the VCPU0 on
cpu (default=None; Value='CPU')
;cpus: CPUS to run the domain on
cpus (default=None; Value='CPUS')
;cpu_cap: Set the maximum amount of cpu. CAP is a percentage that fixes the maximum amount of cpu
cpu_cap (default=None; Value='CAP')
;cpu_weight: Set the cpu time ratio to be allocated to the domain
cpu_weight (default=None; Value='WEIGHT')
;vcpus: # of Virtual CPUS in domain
vcpus (default=1; Value='VCPUS')
;vcpus_avail: Bitmask for virtual CPUs to make available immediately
vcpus_avail (default=None; Value='VCPUS')
;cpuid: Cpuid Description
cpuid (Default=[];Value="IN[,SIN]:eax=EAX,ebx=EBX,ecx=EXC,edx=EDX")
;cpuid_check: Cpuid check Description
cpuid_check (Default=[];Value="IN[,SIN]:eax=EAX,ebx=EBX,ecx=EXC,edx=EDX")
== Networking ==
;hostname: Set the kernel IP hostname
hostname (Default=;Value="NAME")
;ip: Set the kernel IP interface address.
ip (Default=' ' ; Value='IPADDR' )
;interface: Set the kernel IP interface name.
interface (Default="eth0";Value="INTF")
;dhcp: Set the kernel dhcp option
dhcp (Default='off'; Values="off|dhcp")
;vif: Add a network interface with the given MAC address and bridge. The vif is configured by calling the given configuration script. If type is not specified, default is netfront. If mac is not specified a random MAC address is used. If not specified then the network backend chooses it's own MAC address. If bridge is not specified the first bridge found is used. If script is not specified the default script is used. If backend is not specified the default backend driver domain is used. If vifname is not specified the backend virtual interface will have name vifD.N where D is the domain id and N is the interface id. If rate is not specified the default rate is used. If model is not specified the default model is used. If accel is not specified an accelerator plugin module is not used. This option may be repeated to add more than one vif. Specifying vifs will increase the number of interfaces as needed.
vif (Default=[]; Value="type= TYPE, mac=MAC, bridge=BRIDGE, ip=IPADDR, script=SCRIPT," + \ "backend=DOM, vifname=NAME, rate=RATE, model=MODEL, accel=ACCEL" )
;vtpm: Add a TPM interface. On the backend side use the given instance as virtual TPM instance. The given number is merely the preferred instance number. The hotplug script will determine which instance number will actually be assigned to the domain. The associtation between virtual machine and the TPM instance number can be found in /etc/xen/vtpm.db. Use the backend in the given domain. The type parameter can be used to select a specific driver type that the VM can use. To prevent a fully virtualized domain (HVM) from being able to access an emulated device model, you may specify 'paravirtualized' here.
vtpm (Default= [] ; Value= "instance=INSTANCE,backend=DOM,type=TYPE")
;netmask: Set the kernel IP netmask
netmask (Default=' ' ; Value='MASK' )
;gateway: Set the kernel IP gateway.
gateway (Default=' ' ; Value="IPADDR" )
;nfs_server: Set the address of the NFS server for NFS root.
nfs_server (Default=None;Value="IPADDR")
;nfs_root: Set the path of the root NFS directory.
nfs_root (Default=None;Value="PATH")
;device_model: Path to device model program.
device_model (Default=None;Value='FILE')
;uuid: xenstore UUID (universally unique identifier) to use. One will be randomly generated if this option is not set, just like MAC addresses for virtual network interfaces. This must be a unique value across the entire cluster.
uuid (Default=None;Value=)
;ioports: Add a legacy I/O range to a domain, using given params (in hex). For example 'ioports=02f8-02ff'. The option may be repeated to add more than one i/o range
ioports (Default= [] ; Value= 'FROM[-TO]')
== PCI ==
;pci:Add a PCI device to a domain, using given params (in hex). For example 'pci=c0:02.1'. If VSLOT is supplied the device will be inserted into that virtual slot in the guest, else a free slot is selected. If msitranslate is set, MSI-INTx translation is enabled if possible. Guest that doesn't support MSI will get IO-APIC type IRQs translated from physical MSI, HVM only. Default is 1. The option may be repeated to add more than one pci device. If power_mgmt is set, the guest OS will be able to program the power states D0-D3hot of the device, HVM only. Default=0.
pci (Default=[]; Value=BUS:DEV.FUNC[@VSLOT][,msitranslate=0|1][,power_mgmt=0|1]
;vscsi: Add a SCSI device to a domain. The physical device is PDEV, which is exported to the domain as VDEV(X:X:X:X)
vscsi (Default= [];Value= 'PDEV,VDEV[,DOM]')
;pci_msitranslate: Global PCI MSI-INTx translation flag (0=disable;1=enable)
pci_msitranslate (Default=1; Value='TRANSLATE')
;pci_power_mgmt: Global PCI Power Management flag (0=disable; 1=enable)
pci_power_mgmt (Default=0; Value='POWERMGT')
;xen_platform_pci: Is xen_platform_used?
xen_platform_pci (Default=1; Value='0|1')
;serial:Path to serial or pty or vc
serial (Default=' ';Value='FILE')
;keymap: Set keyboard layout used
keymap (Default=' '; Value='FILE')
;usb: Emulate USB devices
usb (Default=0; Value='no|yes')
;usbdevice: Name of USB device
usbdevice (Default=' '; Value='NAME') 
== HVM ==
;viridian:Expose Viridian interface to x86 HVM guest?
viridian (default=0; Value='VIRIDIAN')
;pae: Disable or enable PAE of HVM domain
pae (default=1; Value='PAE')
;hap: Hardware Assisted Paging (HAP) status (0=hap is disabled;1=hap is enabled.)
hap (Default=1; Value='HAP')
;acpi: Disable or enable ACPI of HVM domain.
acpi (default=1; Value='ACPI')
;apic: Disable or enable APIC mode
apic (default=1; Value='APIC')
== Timers ==
;rtc_timeoffset: Set RTC offset
rtc_timeoffset (default=0; Value='RTC_TIMEOFFSET')
;timer_mode: Timer mode (0=delay virtual time when ticks are missed; 1=virtual time is always wallclock time
timer_mode (default=1; Value='TIMER_MODE')
;localtime: Is RTC set to localtime?
Localtime (Default=0; Value='no|yes')
;vpt_align: Enable aligning all periodic vpt to reduce timer interrupts
vpt_align (default=1; Value='VPT_ALIGN')
;vhpt: Log2 of domain VHPT size for IA64
vhpt (default=0; Value='VHPT')
;hpet: Enable virtual high-precision event timer
hpet (default=0; Value='HPET')
== Drivers ==
;irq: Add an IRQ (interrupt line) to a domain. For example 'irq=7'. This option may be repeated to add more than one IRQ
irq (Default = []; Value = 'IRQ')
;blkif: Make the domain a block device backend.
blkif (Default=0; Value='no|yes')
;netif: Make the domain a network interface backend
netif (Default=0; Value='no|yes')
;tpmif: Make the domain a TPM interface backend
tmpif (Default=0; Value='no|yes')
;vfb: Make the domain a framebuffer backend. Both sdl=1 and vnc=1 can be enabled at the same time. For vnc=1, connect an external vncviewer. The server will listen on ADDR (default 127.0.0.1) on port N+5900. N defaults to the domain id. If vncunused=1, the server will try to find an arbitrary unused port above 5900. vncpasswd overrides the XenD configured default password. For sdl=1, a viewer will be started automatically using the given DISPLAY and XAUTHORITY, which default to the current user's ones. OpenGL will be used by default unless opengl is set to 0. keymap overrides the XendD configured default layout file
vfb (Default=[];Value= "vnc=1,sdl=1, vncunused=1, vncdisplay=N, vnclisten=ADDR, display=DISPLAY, xauthority=XAUTHORITY,vncpasswd=PASSWORD, opengl=1, keymap=FILE")
== Disk Devices ==
;root: Set the root= parameter on the kernel command line. Use a device, e.g. /dev/sda1, or /dev/nfs for NFS root
root (Default =' '; Value='DEVICE')
;disk: Add a disk device to a domain. The physical device is DEV, which is exported to the domain as VDEV. The disk is read-only if MODE is 'r', read-write if MODE is 'w'. If DOM is specified it defines the backend driver domain to use for the disk. The option may be repeated to add more than one disk
disk (default=[] ; Value='phy:DEV,VDEV,MODE[,DOM]')
;access_control:Add a security label and the security policy reference that defines it. The local ssid reference is calculated when starting/resuming the domain. At this time, the policy is checked against the active policy as well. This way, migrating through save/restore is covered and local labels are automatically created correctly on the system where a domain is started / resumed. 
access_control (Default= [] ; Value="policy=POLICY,label=LABEL")
== Behavior ==
;on_poweroff: Behavior when a domain exits with reason 'poweroff
on_poweroff (Default=None; Value='destroy|restart|preserve|rename-restart')
;on_reboot: Behavior when a domain exits with reason 'reboot'
on_reboot (Default=None; Value='destroy|restart|preserve|rename-restart')
;on_crash: Behavior when a domain exits with reason 'crash'
on_crash (Default=None; Value='destroy|restart|preserve|rename-restart|coredump-destroy|coredump-restart)
;on_xend_start: Action to preform when xend starts
on_xend_start (Default='ignore'; Value='ignore|start')
;on_xend_stop: Behaviour when Xend stops:- ignore: Domain continues to run;- shutdown: Domain is shutdown;- suspend: Domain is suspended;
on_xend_stop (Default='ignore'; Value='ignore|shutdown|suspend')
;target: Set domain target
target (Default=0; Value='TARGET')
== Graphics and Audio ==
;console: Port to export the domain console on
console = /dev/console
;nographic: Should device models use graphics
nographic (Default=0;Value='no|yes')
;soundhw: Should device models enable audio device
soundhw (Default=' ';Value='audiodev')
;sdl:Should the device model use SDL?
sdl (Default=None;Value=)
;opengl: Enable\Disable OpenGL
opengl (Default=None; Value=' ')
;vnc: Should the device model use VNC?
vnc (Default=None;Value=' ')
;vncunused: Try to find an unused port for the VNC server. Only valid when vnc=1
vncunused (Default=1;Value=' ')
;videoram: Maximum amount of videoram a guest can allocate for frame buffer
videoram (Default=4; Value='MEMORY')
;vncdisplay: VNC Display to use
vncdisplay (Default=None;Value=' ')
;vnclisten: Address for VNC server to listen on
vnclisten (Default=None; Value=' ')
;vncpasswd: Password for VNC console on HVM domain
vncpasswd='xxxxx' (default=None)
;vncviewer: Spawn a vncviewer listening for a vnc server in the domain. The address of the vncviewer is passed to the domain on the kernel command line using 'VNC_SERVER=<host>:<port>'. The port used by vnc is 5900 + DISPLAY. A display value with a free port is chosen if possible. Only valid when vnc=1. DEPRECATED
vncviewer (default = None; Value = 'no|yes')
;vncconsole: Spawn a vncviewer process for the domain's graphical console. Only valid when vnc=1
vncconsole (default=None; Value = 'no|yes')
;stdvga: Use standard VGA or Cirrus Logic Graphics
stdvga (Default=0; Value='no|yes')
;isa: Simulate an ISA only system
isa (Default=0; Value='no|yes')
;guest_os_type: Guest OS type running in HVM
guest_os_type (Default='default'; Value='NAME')
;extra: Set extra arguments to append to the kernel command line
extra (Default=' ' ; Value="ARGS")
;fda: Path to floppy device a
fda (Default=' ';Value=FILE)
;fdb: Path to floppy device b
fdb (Default=' ';Value=FILE)
;display: X11 display to use
display (Default=None;Value='DISPLAY')
;xauthority: X11 authority to use
display (Default=None;Value='XAUTHORITY')
Category:Xen
Category:Overview
Category:Example
Category:Users
Category:Beginners