XenBooting

To Do: Merge with XenHypervisorBootOptions

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 user manual. Options available on version 3.0 are (with examples for common options):

Parameter	Description
|dom0_mem=131072	Initial domain 0 memory allocation in kBytes
|mem=131072	Set the physical RAM address limit. (beyond is ignored)
|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 <baud>,DPS,<io-base>,<irq>.
|console=com1	Comma-separated list of console outputs (see also xencons=)
|sync_console	Force synchronous console output.
|vga=text-80x50	VGA console mode and options
|conswitch	Specify how to switch serial-console input between Xen and DOM0.	Ctrl-A three times
|noacpi	ACPI tables are not parsed
noreboot	Don't reboot the machine automatically on errors.
|nosmp	Disables secondary processors
|ignorebiostables	ACPI and MP tables are ignored (implies noacpi, nosmp)
|watchdog	Run a watchdog NMI on each processor
|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
|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.
|pbd=	Name of serial port for Xen pervasive debugger (and enable pdb)
|conswitch=a	A character pair controlling console switching. CTRL+<char1> 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
|tbuf_size=	Trace buffer size (in pages)
|xenheap_megabytes=	x86-64 only. Size of Xen heap in megabytes, excluding the pfn_info table and allocation bitmap
|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
|apic	Specify NUMA platform...
|noht	Disables Hyper-Threading

XenLinux Boot Options :

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

• `xencons=tty' :: Read http://www.cl.cam.ac.uk/research/srg/netos/xen/readmes/user/user.html 's XenLinux Boot Options