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xl-network-configuration(5)	      Xen	   xl-network-configuration(5)

       xl-network-configuration	- XL Network Configuration Syntax

       This document specifies the xl config file format vif configuration
       option.	It has the following form:

	       vif = [ '<vifspec>', '<vifspec>', ... ]

       where each vifspec is in	this form:


       For example:

	       '' # The	empty string

       These might be specified	in the domain config file like this:

	       vif = [ 'mac=00:16:3E:74:34:32',	'mac=00:16:3e:5f:48:e4,bridge=xenbr1' ]

       More formally, the string is a series of	comma-separated	keyword/value
       pairs. All keywords are optional.

       Each device has a "DEVID" which is its index within the vif list,
       starting	from 0.

       If specified then this option specifies the MAC address inside the
       guest of	this VIF device. The value is a	48-bit number represented as
       six groups of two hexadecimal digits, separated by colons (:).

       The default if this keyword is not specified is to be automatically
       generate	a MAC address inside the space assigned	to Xen's
       Organizationally	Unique Identifier

       If you are choosing a MAC address then it is strongly recommend to
       follow one of the following strategies:

       o   Generate a random sequence of 6 byte, set the locally administered
	   bit (bit 2 of the first byte) and clear the multicast bit (bit 1 of
	   the first byte). In other words the first byte should have the bit
	   pattern xxxxxx10 (where x is	a randomly generated bit) and the
	   remaining 5 bytes are randomly generated See
	   [] for more	details	the
	   structure of	a MAC address.

       o   Allocate an address from within the space defined by	your
	   organization's OUI (if you have one)	following your organization's
	   procedures for doing	so.

       o   Allocate an address from within the space defined by	Xen's OUI
	   (00:16:3e). Taking care not to clash	with other users of the
	   physical network segment where this VIF will	reside.

       If you have an OUI for your own use then	that is	the preferred
       strategy. Otherwise in general you should prefer	to generate a random
       MAC and set the locally administered bit	since this allows for more
       bits of randomness than using the Xen OUI.

       Specifies the name of the network bridge	which this VIF should be added
       to. The default is "xenbr0". The	bridge must be configured using	your
       distribution's network configuration tools. See the wiki
       for guidance and	examples.

       Specifies the name of the network interface which has an	IP and which
       is in the network the VIF should	communicate with. This is used in the
       host by the vif-route hotplug script. See wiki
       <> for	guidance and examples.

       NOTE: netdev is a deprecated alias of this option.

       This keyword is valid for HVM guests only.

       Specifies the type of device to valid values are:

       o   "ioemu" (default) --	this device will be provided as	an emulate
	   device to the guest and also	as a paravirtualised device which the
	   guest may choose to use instead if it has suitable drivers

       o   "vif" -- this device	will be	provided as a paravirtualised device

       This keyword is valid for HVM guest devices with	"type=ioemu" only.

       Specifies the type device to emulated for this guest. Valid values are:

       o   "rtl8139" (default) -- Realtek RTL8139

       o   "e1000" -- Intel E1000

       o   in principle	any device supported by	your device model

       Specifies the backend device name for the virtual device.

       If the domain is	an HVM domain then the associated emulated (tap)
       device will have	a "-emu" suffice added.

       The default name	for the	virtual	device is "vifDOMID.DEVID" where
       "DOMID" is the guest domain ID and "DEVID" is the device	number.
       Likewise	the default tap	name is	"vifDOMID.DEVID-emu".

       Specifies the hotplug script to run to configure	this device (e.g. to
       add it to the relevant bridge). Defaults	to "XEN_SCRIPT_DIR/vif-bridge"
       but can be set to any script. Some example scripts are installed	in

       Specifies the IP	address	for the	device,	the default is not to specify
       an IP address.

       What, if	any, effect this has depends on	the hotplug script which is
       configured. A typically behaviour (exhibited by the example hotplug
       scripts)	if set might be	to configure firewall rules to allow only the
       specified IP address to be used by the guest (blocking all others).

       Specifies the backend domain which this device should attach to.	This
       defaults	to domain 0.  Specifying another domain	requires setting up a
       driver domain which is outside the scope	of this	document.

       Specifies the rate at which the outgoing	traffic	will be	limited	to.
       The default if this keyword is not specified is unlimited.

       The rate	may be specified as "/s" or optionally "/s@".

       o   "RATE" is in	bytes and can accept suffixes:

	   o   GB, MB, KB, B for bytes.

	   o   Gb, Mb, Kb, b for bits.

       o   "INTERVAL" is in microseconds and can accept	suffixes: ms, us, s.
	   It determines the frequency at which	the vif	transmission credit is
	   replenished.	The default is 50ms.

       Vif rate	limiting is credit-based. It means that	for "1MB/s@20ms", the
       available credit	will be	equivalent of the traffic you would have done
       at "1MB/s" during 20ms. This will results in a credit of	20,000 bytes
       replenished every 20,000	us.

       For example:

	       'rate=10Mb/s' --	meaning	up to 10 megabits every	second
	       'rate=250KB/s' -- meaning up to 250 kilobytes every second
	       'rate=1MB/s@20ms' -- meaning 20,000 bytes in every 20 millisecond period

       NOTE: The actual	underlying limits of rate limiting are dependent on
       the underlying netback implementation.

       Specifies the devid manually instead of letting xl choose the lowest
       index available.

       NOTE: This should not be	set unless you have a reason to.

4.14.0				  2020-07-23	   xl-network-configuration(5)

NAME | SYNTAX | Keywords

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