xen boot arguments

Xen systems are typically booted with GrUB. The GrUB "kernel" is Xen itself. The kernel image for domain 0 is given to grub as the first "module". An initrd for domain 0, if required, is specified as a further module. A number of options can be passed to Xen on the command line.

• For an up-to-date list see the . Options available on version 3.0 are (with examples for common options):

Parameter	Description	Default
dom0_mem=131072	Initial domain 0 memory allocation in kBytes	16000kBytes
mem=131072	Set the physical RAM address limit. (beyond is ignored)	16000kBytes
dom0_vcpus_pin	Pins domain 0 VCPUs on their respective
com1=115200,8n1 com2=	Serial console details for Xen (Linux will need its own serial console configuration if required). Format is ,DPS,,.
console=com1	Comma-separated list of console outputs (see also )	com1,vga
sync_console	Force synchronous console output.	async, except on major errors
vga=text-80x50	VGA console mode and options	vga=text-80x25
conswitch	Specify how to switch serial-console input between Xen and DOM0.	Ctrl-A three times|
noacpi	ACPI tables are not parsed	Tables are parsed
noreboot	Don't reboot the machine automatically on errors.	reboot on errors
nosmp	Disables secondary processors	SMP Enabled
ignorebiostables	ACPI and MP tables are ignored (implies noacpi, nosmp)	Tables are parsed
watchdog	Run a watchdog NMI on each processor	Not run
physdev_dom0_hide=	List of PCI slots to hide from domain 0, Format is '(%02x:%02x.%1x)(%02x:%02x.%1x)' and so on.
badpage=	Comma-separated list of hexadecimal page numbers containing bad bytes. e.g. 'badpage=0x3f45,0x8a321'
sched=bvt	Scheduler - see Users' Manual	sched=credit
leveltrigger=	Force an IO-APIC-routed IRQ to be level-triggered. Example: 'leveltrigger=4,5,6,20 edgetrigger=21'
edgetrigger=	Force an IO-APIC-routed IRQ to be edge-triggered. Example: 'leveltrigger=4,5,6,20 edgetrigger=21'
nmi=	One of: fatal: Xen prints diagnostic message and then hangs. dom0: The NMI is virtualised to DOM0. ignore: The NMI error is cleared and ignored.	dom0
pbd=	Name of serial port for Xen pervasive debugger (and enable pdb)	Disabled
conswitch=a	A character pair controlling console switching. CTRL+ is used to switch console input between Xen and DOM0. Char 2: If this character is 'x', then do not auto-switch to DOM0 when it boots. Any other value, or omitting the char, enables auto-switch	a
tbuf_size=	Trace buffer size (in pages)	10
xenheap_megabytes=	x86-64 only. Size of Xen heap in megabytes, excluding the pfn_info table and allocation bitmap	defined: XENHEAP_DEFAULT_MB as 16
noirqbalance	Disable software IRQ balancing and affinity.
apic_verbosity	Print more detailed information about local APIC and IOAPIC
lapic / nolapic	Force / Ignore use of local APIC	auto
apic	Specify NUMA platform...
Old options (version 2.0)
noht	Disables Hyper-Threading	HT Enabled

XenLinux Boot Options :

In addition to the standard Linux kernel boot options, we support:

* `xencons=tty'

Read 's Boot Options