|
NAME | SYNOPSIS | DESCRIPTION | [MATCH] SECTION OPTIONS | [LINK] SECTION OPTIONS | [SR-IOV] SECTION OPTIONS | EXAMPLES | SEE ALSO | NOTES | COLOPHON |
|
|
|
SYSTEMD.LINK(5) systemd.link SYSTEMD.LINK(5)
systemd.link - Network device configuration
link.link
A plain ini-style text file that encodes configuration for
matching network devices, used by systemd-udevd(8) and in
particular its net_setup_link builtin. See systemd.syntax(7) for
a general description of the syntax.
The .link files are read from the files located in the system
network directory /usr/lib/systemd/network and
/usr/local/lib/systemd/network, the volatile runtime network
directory /run/systemd/network, and the local administration
network directory /etc/systemd/network. All configuration files
are collectively sorted and processed in alphanumeric order,
regardless of the directories in which they live. However, files
with identical filenames replace each other. It is recommended
that each filename is prefixed with a number (e.g.
10-eth0.link). Otherwise, the default .link files or those
generated by systemd-network-generator.service(8) may take
precedence over user configured files. Files in /etc/ have the
highest priority, files in /run/ take precedence over files with
the same name in /usr/lib/. This can be used to override a
system-supplied link file with a local file if needed. As a
special case, an empty file (file size 0) or symlink with the
same name pointing to /dev/null disables the configuration file
entirely (it is "masked").
Along with the link file foo.link, a "drop-in" directory
foo.link.d/ may exist. All files with the suffix ".conf" from
this directory will be merged in the alphanumeric order and
parsed after the main file itself has been parsed. This is useful
to alter or add configuration settings, without having to modify
the main configuration file. Each drop-in file must have
appropriate section headers.
In addition to /etc/systemd/network, drop-in ".d" directories can
be placed in /usr/lib/systemd/network or /run/systemd/network
directories. Drop-in files in /etc/ take precedence over those in
/run/ which in turn take precedence over those in /usr/lib/.
Drop-in files under any of these directories take precedence over
the main link file wherever located.
The link file contains a [Match] section, which determines if a
given link file may be applied to a given device, as well as a
[Link] section specifying how the device should be configured.
The first (in lexical order) of the link files that matches a
given device is applied. Note that a default file 99-default.link
is shipped by the system. Any user-supplied .link should hence
have a lexically earlier name to be considered at all.
See udevadm(8) for diagnosing problems with .link files.
A link file is said to match an interface if all matches
specified by the [Match] section are satisfied. When a link file
does not contain valid settings in [Match] section, then the file
will match all interfaces and systemd-udevd warns about that.
Hint: to avoid the warning and to make it clear that all
interfaces shall be matched, add the following:
OriginalName=*
The first (in alphanumeric order) of the link files that matches
a given interface is applied, all later files are ignored, even
if they match as well. The following keys are accepted:
MACAddress=
A whitespace-separated list of hardware addresses. The
acceptable formats are:
colon-delimited hexadecimal
Each field must be one byte. E.g. "12:34:56:78:90:ab" or
"AA:BB:CC:DD:EE:FF".
hyphen-delimited hexadecimal
Each field must be one byte. E.g. "12-34-56-78-90-ab" or
"AA-BB-CC-DD-EE-FF".
dot-delimited hexadecimal
Each field must be two bytes. E.g. "1234.5678.90ab" or
"AABB.CCDD.EEFF".
IPv4 address format
E.g. "127.0.0.1" or "192.168.0.1".
IPv6 address format
E.g. "2001:0db8:85a3::8a2e:0370:7334" or "::1".
The total length of each MAC address must be 4 (for IPv4
tunnel), 6 (for Ethernet), 16 (for IPv6 tunnel), or 20 (for
InfiniBand). This option may appear more than once, in which
case the lists are merged. If the empty string is assigned to
this option, the list of hardware addresses defined prior to
this is reset. Defaults to unset.
PermanentMACAddress=
A whitespace-separated list of hardware's permanent
addresses. While MACAddress= matches the device's current MAC
address, this matches the device's permanent MAC address,
which may be different from the current one. Use full colon-,
hyphen- or dot-delimited hexadecimal, or IPv4 or IPv6 address
format. This option may appear more than once, in which case
the lists are merged. If the empty string is assigned to this
option, the list of hardware addresses defined prior to this
is reset. Defaults to unset.
Path=
A whitespace-separated list of shell-style globs matching the
persistent path, as exposed by the udev property ID_PATH.
Driver=
A whitespace-separated list of shell-style globs matching the
driver currently bound to the device, as exposed by the udev
property ID_NET_DRIVER of its parent device, or if that is
not set, the driver as exposed by ethtool -i of the device
itself. If the list is prefixed with a "!", the test is
inverted.
Type=
A whitespace-separated list of shell-style globs matching the
device type, as exposed by networkctl list. If the list is
prefixed with a "!", the test is inverted. Some valid values
are "ether", "loopback", "wlan", "wwan". Valid types are
named either from the udev "DEVTYPE" attribute, or "ARPHRD_"
macros in linux/if_arp.h, so this is not comprehensive.
Kind=
A whitespace-separated list of shell-style globs matching the
device kind, as exposed by networkctl status INTERFACE or ip
-d link show INTERFACE. If the list is prefixed with a "!",
the test is inverted. Some valid values are "bond", "bridge",
"gre", "tun", "veth". Valid kinds are given by netlink's
"IFLA_INFO_KIND" attribute, so this is not comprehensive.
Property=
A whitespace-separated list of udev property names with their
values after equals sign ("="). If multiple properties are
specified, the test results are ANDed. If the list is
prefixed with a "!", the test is inverted. If a value
contains white spaces, then please quote whole key and value
pair. If a value contains quotation, then please escape the
quotation with "\".
Example: if a .link file has the following:
Property=ID_MODEL_ID=9999 "ID_VENDOR_FROM_DATABASE=vendor name" "KEY=with \"quotation\""
then, the .link file matches only when an interface has all
the above three properties.
OriginalName=
A whitespace-separated list of shell-style globs matching the
device name, as exposed by the udev property "INTERFACE".
This cannot be used to match on names that have already been
changed from userspace. Caution is advised when matching on
kernel-assigned names, as they are known to be unstable
between reboots.
Host=
Matches against the hostname or machine ID of the host. See
ConditionHost= in systemd.unit(5) for details. When prefixed
with an exclamation mark ("!"), the result is negated. If an
empty string is assigned, the previously assigned value is
cleared.
Virtualization=
Checks whether the system is executed in a virtualized
environment and optionally test whether it is a specific
implementation. See ConditionVirtualization= in
systemd.unit(5) for details. When prefixed with an
exclamation mark ("!"), the result is negated. If an empty
string is assigned, the previously assigned value is cleared.
KernelCommandLine=
Checks whether a specific kernel command line option is set.
See ConditionKernelCommandLine= in systemd.unit(5) for
details. When prefixed with an exclamation mark ("!"), the
result is negated. If an empty string is assigned, the
previously assigned value is cleared.
KernelVersion=
Checks whether the kernel version (as reported by uname -r)
matches a certain expression. See ConditionKernelVersion= in
systemd.unit(5) for details. When prefixed with an
exclamation mark ("!"), the result is negated. If an empty
string is assigned, the previously assigned value is cleared.
Credential=
Checks whether the specified credential was passed to the
systemd-networkd.service service. See System and Service
Credentials[1] for details. When prefixed with an exclamation
mark ("!"), the result is negated. If an empty string is
assigned, the previously assigned value is cleared.
Architecture=
Checks whether the system is running on a specific
architecture. See ConditionArchitecture= in systemd.unit(5)
for details. When prefixed with an exclamation mark ("!"),
the result is negated. If an empty string is assigned, the
previously assigned value is cleared.
Firmware=
Checks whether the system is running on a machine with the
specified firmware. See ConditionFirmware= in systemd.unit(5)
for details. When prefixed with an exclamation mark ("!"),
the result is negated. If an empty string is assigned, the
previously assigned value is cleared.
The [Link] section accepts the following keys:
Description=
A description of the device.
Alias=
The ifalias interface property is set to this value.
MACAddressPolicy=
The policy by which the MAC address should be set. The
available policies are:
persistent
If the hardware has a persistent MAC address, as most
hardware should, and if it is used by the kernel, nothing
is done. Otherwise, a new MAC address is generated which
is guaranteed to be the same on every boot for the given
machine and the given device, but which is otherwise
random. This feature depends on ID_NET_NAME_* properties
to exist for the link. On hardware where these properties
are not set, the generation of a persistent MAC address
will fail.
random
If the kernel is using a random MAC address, nothing is
done. Otherwise, a new address is randomly generated each
time the device appears, typically at boot. Either way,
the random address will have the "unicast" and "locally
administered" bits set.
none
Keeps the MAC address assigned by the kernel. Or use the
MAC address specified in MACAddress=.
An empty string assignment is equivalent to setting "none".
MACAddress=
The interface MAC address to use. For this setting to take
effect, MACAddressPolicy= must either be unset, empty, or
"none".
NamePolicy=
An ordered, space-separated list of policies by which the
interface name should be set. NamePolicy= may be disabled by
specifying net.ifnames=0 on the kernel command line. Each of
the policies may fail, and the first successful one is used.
The name is not set directly, but is exported to udev as the
property ID_NET_NAME, which is, by default, used by a
udev(7), rule to set NAME. The available policies are:
kernel
If the kernel claims that the name it has set for a
device is predictable, then no renaming is performed.
database
The name is set based on entries in the udev's Hardware
Database with the key ID_NET_NAME_FROM_DATABASE.
onboard
The name is set based on information given by the
firmware for on-board devices, as exported by the udev
property ID_NET_NAME_ONBOARD. See
systemd.net-naming-scheme(7).
slot
The name is set based on information given by the
firmware for hot-plug devices, as exported by the udev
property ID_NET_NAME_SLOT. See
systemd.net-naming-scheme(7).
path
The name is set based on the device's physical location,
as exported by the udev property ID_NET_NAME_PATH. See
systemd.net-naming-scheme(7).
mac
The name is set based on the device's persistent MAC
address, as exported by the udev property
ID_NET_NAME_MAC. See systemd.net-naming-scheme(7).
keep
If the device already had a name given by userspace (as
part of creation of the device or a rename), keep it.
Name=
The interface name to use. This option has lower precedence
than NamePolicy=, so for this setting to take effect,
NamePolicy= must either be unset, empty, disabled, or all
policies configured there must fail. Also see the example
below with "Name=dmz0".
Note that specifying a name that the kernel might use for
another interface (for example "eth0") is dangerous because
the name assignment done by udev will race with the
assignment done by the kernel, and only one interface may use
the name. Depending on the order of operations, either udev
or the kernel will win, making the naming unpredictable. It
is best to use some different prefix, for example
"internal0"/"external0" or "lan0"/"lan1"/"lan3".
Interface names must have a minimum length of 1 character and
a maximum length of 15 characters, and may contain any 7bit
ASCII character, with the exception of control characters,
":", "/" and "%". While "." is an allowed character, it's
recommended to avoid it when naming interfaces as various
tools (such as resolvconf(1)) use it as separator character.
Also, fully numeric interface names are not allowed (in order
to avoid ambiguity with interface specification by numeric
indexes), as are the special strings ".", "..", "all" and
"default".
AlternativeNamesPolicy=
A space-separated list of policies by which the interface's
alternative names should be set. Each of the policies may
fail, and all successful policies are used. The available
policies are "database", "onboard", "slot", "path", and
"mac". If the kernel does not support the alternative names,
then this setting will be ignored.
AlternativeName=
The alternative interface name to use. This option can be
specified multiple times. If the empty string is assigned to
this option, the list is reset, and all prior assignments
have no effect. If the kernel does not support the
alternative names, then this setting will be ignored.
Alternative interface names may be used to identify
interfaces in various tools. In contrast to the primary name
(as configured with Name= above) there may be multiple
alternative names referring to the same interface.
Alternative names may have a maximum length of 127
characters, in contrast to the 15 allowed for the primary
interface name, but otherwise are subject to the same naming
constraints.
TransmitQueues=
Specifies the device's number of transmit queues. An integer
in the range 1...4096. When unset, the kernel's default will
be used.
ReceiveQueues=
Specifies the device's number of receive queues. An integer
in the range 1...4096. When unset, the kernel's default will
be used.
TransmitQueueLength=
Specifies the transmit queue length of the device in number
of packets. An unsigned integer in the range 0...4294967294.
When unset, the kernel's default will be used.
MTUBytes=
The maximum transmission unit in bytes to set for the device.
The usual suffixes K, M, G are supported and are understood
to the base of 1024.
BitsPerSecond=
The speed to set for the device, the value is rounded down to
the nearest Mbps. The usual suffixes K, M, G are supported
and are understood to the base of 1000.
Duplex=
The duplex mode to set for the device. The accepted values
are half and full.
AutoNegotiation=
Takes a boolean. If set to yes, automatic negotiation of
transmission parameters is enabled. Autonegotiation is a
procedure by which two connected ethernet devices choose
common transmission parameters, such as speed, duplex mode,
and flow control. When unset, the kernel's default will be
used.
Note that if autonegotiation is enabled, speed and duplex
settings are read-only. If autonegotiation is disabled, speed
and duplex settings are writable if the driver supports
multiple link modes.
WakeOnLan=
The Wake-on-LAN policy to set for the device. Takes the
special value "off" which disables Wake-on-LAN, or space
separated list of the following words:
phy
Wake on PHY activity.
unicast
Wake on unicast messages.
multicast
Wake on multicast messages.
broadcast
Wake on broadcast messages.
arp
Wake on ARP.
magic
Wake on receipt of a magic packet.
secureon
Enable SecureOn password for MagicPacket. Implied when
WakeOnLanPassword= is specified. If specified without
WakeOnLanPassword= option, then the password is read from
the credential "LINK.link.wol.password" (e.g.,
"60-foo.link.wol.password"), and if the credential not
found, then read from "wol.password". See
LoadCredential=/SetCredential= in systemd.exec(1) for
details. The password in the credential, must be 6 bytes
in hex format with each byte separated by a colon (":")
like an Ethernet MAC address, e.g., "aa:bb:cc:dd:ee:ff".
Defaults to unset, and the device's default will be used.
This setting can be specified multiple times. If an empty
string is assigned, then the all previous assignments are
cleared.
WakeOnLanPassword=
Specifies the SecureOn password for MagicPacket. Takes an
absolute path to a regular file or an AF_UNIX stream socket,
or the plain password. When a path to a regular file is
specified, the password is read from it. When an AF_UNIX
stream socket is specified, a connection is made to it and
the password is read from it. The password must be 6 bytes in
hex format with each byte separated by a colon (":") like an
Ethernet MAC address, e.g., "aa:bb:cc:dd:ee:ff". This implies
WakeOnLan=secureon. Defaults to unset, and the current value
will not be changed.
Port=
The port option is used to select the device port. The
supported values are:
tp
An Ethernet interface using Twisted-Pair cable as the
medium.
aui
Attachment Unit Interface (AUI). Normally used with hubs.
bnc
An Ethernet interface using BNC connectors and co-axial
cable.
mii
An Ethernet interface using a Media Independent Interface
(MII).
fibre
An Ethernet interface using Optical Fibre as the medium.
Advertise=
This sets what speeds and duplex modes of operation are
advertised for auto-negotiation. This implies
"AutoNegotiation=yes". The supported values are:
Table 1. Supported advertise values
┌───────────────────┬──────────────┬─────────────┐
│Advertise │ Speed (Mbps) │ Duplex Mode │
├───────────────────┼──────────────┼─────────────┤
│10baset-half │ 10 │ half │
├───────────────────┼──────────────┼─────────────┤
│10baset-full │ 10 │ full │
├───────────────────┼──────────────┼─────────────┤
│100baset-half │ 100 │ half │
├───────────────────┼──────────────┼─────────────┤
│100baset-full │ 100 │ full │
├───────────────────┼──────────────┼─────────────┤
│1000baset-half │ 1000 │ half │
├───────────────────┼──────────────┼─────────────┤
│1000baset-full │ 1000 │ full │
├───────────────────┼──────────────┼─────────────┤
│10000baset-full │ 10000 │ full │
├───────────────────┼──────────────┼─────────────┤
│2500basex-full │ 2500 │ full │
├───────────────────┼──────────────┼─────────────┤
│1000basekx-full │ 1000 │ full │
├───────────────────┼──────────────┼─────────────┤
│10000basekx4-full │ 10000 │ full │
├───────────────────┼──────────────┼─────────────┤
│10000basekr-full │ 10000 │ full │
├───────────────────┼──────────────┼─────────────┤
│10000baser-fec │ 10000 │ full │
├───────────────────┼──────────────┼─────────────┤
│20000basemld2-full │ 20000 │ full │
├───────────────────┼──────────────┼─────────────┤
│20000basekr2-full │ 20000 │ full │
└───────────────────┴──────────────┴─────────────┘
By default this is unset, i.e. all possible modes will be
advertised. This option may be specified more than once, in
which case all specified speeds and modes are advertised. If
the empty string is assigned to this option, the list is
reset, and all prior assignments have no effect.
ReceiveChecksumOffload=
Takes a boolean. If set to true, hardware offload for
checksumming of ingress network packets is enabled. When
unset, the kernel's default will be used.
TransmitChecksumOffload=
Takes a boolean. If set to true, hardware offload for
checksumming of egress network packets is enabled. When
unset, the kernel's default will be used.
TCPSegmentationOffload=
Takes a boolean. If set to true, TCP Segmentation Offload
(TSO) is enabled. When unset, the kernel's default will be
used.
TCP6SegmentationOffload=
Takes a boolean. If set to true, TCP6 Segmentation Offload
(tx-tcp6-segmentation) is enabled. When unset, the kernel's
default will be used.
GenericSegmentationOffload=
Takes a boolean. If set to true, Generic Segmentation Offload
(GSO) is enabled. When unset, the kernel's default will be
used.
GenericReceiveOffload=
Takes a boolean. If set to true, Generic Receive Offload
(GRO) is enabled. When unset, the kernel's default will be
used.
GenericReceiveOffloadHardware=
Takes a boolean. If set to true, hardware accelerated Generic
Receive Offload (GRO) is enabled. When unset, the kernel's
default will be used.
LargeReceiveOffload=
Takes a boolean. If set to true, Large Receive Offload (LRO)
is enabled. When unset, the kernel's default will be used.
ReceiveVLANCTAGHardwareAcceleration=
Takes a boolean. If set to true, receive VLAN CTAG hardware
acceleration is enabled. When unset, the kernel's default
will be used.
TransmitVLANCTAGHardwareAcceleration=
Takes a boolean. If set to true, transmit VLAN CTAG hardware
acceleration is enabled. When unset, the kernel's default
will be used.
ReceiveVLANCTAGFilter=
Takes a boolean. If set to true, receive filtering on VLAN
CTAGs is enabled. When unset, the kernel's default will be
used.
TransmitVLANSTAGHardwareAcceleration=
Takes a boolean. If set to true, transmit VLAN STAG hardware
acceleration is enabled. When unset, the kernel's default
will be used.
NTupleFilter=
Takes a boolean. If set to true, receive N-tuple filters and
actions are enabled. When unset, the kernel's default will be
used.
RxChannels=, TxChannels=, OtherChannels=, CombinedChannels=
Specifies the number of receive, transmit, other, or combined
channels, respectively. Takes an unsigned integer in the
range 1...4294967295 or "max". If set to "max", the
advertised maximum value of the hardware will be used. When
unset, the number will not be changed. Defaults to unset.
RxBufferSize=, RxMiniBufferSize=, RxJumboBufferSize=,
TxBufferSize=
Specifies the maximum number of pending packets in the NIC
receive buffer, mini receive buffer, jumbo receive buffer, or
transmit buffer, respectively. Takes an unsigned integer in
the range 1...4294967295 or "max". If set to "max", the
advertised maximum value of the hardware will be used. When
unset, the number will not be changed. Defaults to unset.
RxFlowControl=
Takes a boolean. When set, enables receive flow control, also
known as the ethernet receive PAUSE message (generate and
send ethernet PAUSE frames). When unset, the kernel's default
will be used.
TxFlowControl=
Takes a boolean. When set, enables transmit flow control,
also known as the ethernet transmit PAUSE message (respond to
received ethernet PAUSE frames). When unset, the kernel's
default will be used.
AutoNegotiationFlowControl=
Takes a boolean. When set, auto negotiation enables the
interface to exchange state advertisements with the connected
peer so that the two devices can agree on the ethernet PAUSE
configuration. When unset, the kernel's default will be used.
GenericSegmentOffloadMaxBytes=
Specifies the maximum size of a Generic Segment Offload (GSO)
packet the device should accept. The usual suffixes K, M, G
are supported and are understood to the base of 1024. An
unsigned integer in the range 1...65536. Defaults to unset.
GenericSegmentOffloadMaxSegments=
Specifies the maximum number of Generic Segment Offload (GSO)
segments the device should accept. An unsigned integer in the
range 1...65535. Defaults to unset.
UseAdaptiveRxCoalesce=, UseAdaptiveTxCoalesce=
Boolean properties that, when set, enable/disable adaptive
Rx/Tx coalescing if the hardware supports it. When unset, the
kernel's default will be used.
RxCoalesceSec=, RxCoalesceIrqSec=, RxCoalesceLowSec=,
RxCoalesceHighSec=, TxCoalesceSec=, TxCoalesceIrqSec=,
TxCoalesceLowSec=, TxCoalesceHighSec=
These properties configure the delay before Rx/Tx interrupts
are generated after a packet is sent/received. The "Irq"
properties come into effect when the host is servicing an
IRQ. The "Low" and "High" properties come into effect when
the packet rate drops below the low packet rate threshold or
exceeds the high packet rate threshold respectively if
adaptive Rx/Tx coalescing is enabled. When unset, the
kernel's defaults will be used.
RxMaxCoalescedFrames=, RxMaxCoalescedIrqFrames=,
RxMaxCoalescedLowFrames=, RxMaxCoalescedHighFrames=,
TxMaxCoalescedFrames=, TxMaxCoalescedIrqFrames=,
TxMaxCoalescedLowFrames=, TxMaxCoalescedHighFrames=
These properties configure the maximum number of frames that
are sent/received before a Rx/Tx interrupt is generated. The
"Irq" properties come into effect when the host is servicing
an IRQ. The "Low" and "High" properties come into effect when
the packet rate drops below the low packet rate threshold or
exceeds the high packet rate threshold respectively if
adaptive Rx/Tx coalescing is enabled. When unset, the
kernel's defaults will be used.
CoalescePacketRateLow=, CoalescePacketRateHigh=
These properties configure the low and high packet rate
(expressed in packets per second) threshold respectively and
are used to determine when the corresponding coalescing
settings for low and high packet rates come into effect if
adaptive Rx/Tx coalescing is enabled. If unset, the kernel's
defaults will be used.
CoalescePacketRateSampleIntervalSec=
Configures how often to sample the packet rate used for
adaptive Rx/Tx coalescing. This property cannot be zero. This
lowest time granularity supported by this property is
seconds. Partial seconds will be rounded up before being
passed to the kernel. If unset, the kernel's default will be
used.
StatisticsBlockCoalesceSec=
How long to delay driver in-memory statistics block updates.
If the driver does not have an in-memory statistic block,
this property is ignored. This property cannot be zero. If
unset, the kernel's default will be used.
MDI=
Specifies the medium dependent interface (MDI) mode for the
interface. A MDI describes the interface from a physical
layer implementation to the physical medium used to carry the
transmission. Takes one of the following words: "straight"
(or equivalently: "mdi"), "crossover" (or equivalently:
"mdi-x", "mdix"), and "auto". When "straight", the MDI
straight through mode will be used. When "crossover", the MDI
crossover (MDI-X) mode will be used. When "auto", the MDI
status is automatically detected. Defaults to unset, and the
kernel's default will be used.
SR-IOVVirtualFunctions=
Specifies the number of SR-IOV virtual functions. Takes an
integer in the range 0...2147483647. Defaults to unset, and
automatically determined from the values specified in the
VirtualFunction= settings in the [SR-IOV] sections.
The [SR-IOV] section accepts the following keys. Specify several
[SR-IOV] sections to configure several SR-IOVs. SR-IOV provides
the ability to partition a single physical PCI resource into
virtual PCI functions which can then be injected into a VM. In
the case of network VFs, SR-IOV improves north-south network
performance (that is, traffic with endpoints outside the host
machine) by allowing traffic to bypass the host machine’s network
stack.
VirtualFunction=
Specifies a Virtual Function (VF), lightweight PCIe function
designed solely to move data in and out. Takes an integer in
the range 0...2147483646. This option is compulsory.
VLANId=
Specifies VLAN ID of the virtual function. Takes an integer
in the range 1...4095.
QualityOfService=
Specifies quality of service of the virtual function. Takes
an integer in the range 1...4294967294.
VLANProtocol=
Specifies VLAN protocol of the virtual function. Takes
"802.1Q" or "802.1ad".
MACSpoofCheck=
Takes a boolean. Controls the MAC spoof checking. When unset,
the kernel's default will be used.
QueryReceiveSideScaling=
Takes a boolean. Toggle the ability of querying the receive
side scaling (RSS) configuration of the virtual function
(VF). The VF RSS information like RSS hash key may be
considered sensitive on some devices where this information
is shared between VF and the physical function (PF). When
unset, the kernel's default will be used.
Trust=
Takes a boolean. Allows one to set trust mode of the virtual
function (VF). When set, VF users can set a specific feature
which may impact security and/or performance. When unset, the
kernel's default will be used.
LinkState=
Allows one to set the link state of the virtual function
(VF). Takes a boolean or a special value "auto". Setting to
"auto" means a reflection of the physical function (PF) link
state, "yes" lets the VF to communicate with other VFs on
this host even if the PF link state is down, "no" causes the
hardware to drop any packets sent by the VF. When unset, the
kernel's default will be used.
MACAddress=
Specifies the MAC address for the virtual function.
Example 1. /usr/lib/systemd/network/99-default.link
The link file 99-default.link that is shipped with systemd
defines the default naming policy for links.
[Link]
NamePolicy=kernel database onboard slot path
MACAddressPolicy=persistent
Example 2. /etc/systemd/network/10-dmz.link
This example assigns the fixed name "dmz0" to the interface with
the MAC address 00:a0:de:63:7a:e6:
[Match]
MACAddress=00:a0:de:63:7a:e6
[Link]
Name=dmz0
NamePolicy= is not set, so Name= takes effect. We use the "10-"
prefix to order this file early in the list. Note that it needs
to be before "99-link", i.e. it needs a numerical prefix, to have
any effect at all.
Example 3. Debugging NamePolicy= assignments
$ sudo SYSTEMD_LOG_LEVEL=debug udevadm test-builtin net_setup_link /sys/class/net/hub0
...
Parsed configuration file /usr/lib/systemd/network/99-default.link
Parsed configuration file /etc/systemd/network/10-eth0.link
ID_NET_DRIVER=cdc_ether
Config file /etc/systemd/network/10-eth0.link applies to device hub0
link_config: autonegotiation is unset or enabled, the speed and duplex are not writable.
hub0: Device has name_assign_type=4
Using default interface naming scheme 'v240'.
hub0: Policies didn't yield a name, using specified Name=hub0.
ID_NET_LINK_FILE=/etc/systemd/network/10-eth0.link
ID_NET_NAME=hub0
...
Explicit Name= configuration wins in this case.
sudo SYSTEMD_LOG_LEVEL=debug udevadm test-builtin net_setup_link /sys/class/net/enp0s31f6
...
Parsed configuration file /usr/lib/systemd/network/99-default.link
Parsed configuration file /etc/systemd/network/10-eth0.link
Created link configuration context.
ID_NET_DRIVER=e1000e
Config file /usr/lib/systemd/network/99-default.link applies to device enp0s31f6
link_config: autonegotiation is unset or enabled, the speed and duplex are not writable.
enp0s31f6: Device has name_assign_type=4
Using default interface naming scheme 'v240'.
enp0s31f6: Policy *keep*: keeping existing userspace name
enp0s31f6: Device has addr_assign_type=0
enp0s31f6: MAC on the device already matches policy *persistent*
ID_NET_LINK_FILE=/usr/lib/systemd/network/99-default.link
...
In this case, the interface was already renamed, so the keep
policy specified as the first option in 99-default.link means
that the existing name is preserved. If keep was removed, or if
were in boot before the renaming has happened, we might get the
following instead:
enp0s31f6: Policy *path* yields "enp0s31f6".
enp0s31f6: Device has addr_assign_type=0
enp0s31f6: MAC on the device already matches policy *persistent*
ID_NET_LINK_FILE=/usr/lib/systemd/network/99-default.link
ID_NET_NAME=enp0s31f6
...
Please note that the details of output are subject to change.
Example 4. /etc/systemd/network/10-internet.link
This example assigns the fixed name "internet0" to the interface
with the device path "pci-0000:00:1a.0-*":
[Match]
Path=pci-0000:00:1a.0-*
[Link]
Name=internet0
Example 5. /etc/systemd/network/25-wireless.link
Here's an overly complex example that shows the use of a large
number of [Match] and [Link] settings.
[Match]
MACAddress=12:34:56:78:9a:bc
Driver=brcmsmac
Path=pci-0000:02:00.0-*
Type=wlan
Virtualization=no
Host=my-laptop
Architecture=x86-64
[Link]
Name=wireless0
MTUBytes=1450
BitsPerSecond=10M
WakeOnLan=magic
MACAddress=cb:a9:87:65:43:21
systemd-udevd.service(8), udevadm(8), systemd.netdev(5),
systemd.network(5), systemd-network-generator.service(8)
1. System and Service Credentials
https://systemd.io/CREDENTIALS
This page is part of the systemd (systemd system and service
manager) project. Information about the project can be found at
⟨http://www.freedesktop.org/wiki/Software/systemd⟩. If you have
a bug report for this manual page, see
⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
This page was obtained from the project's upstream Git repository
⟨https://github.com/systemd/systemd.git⟩ on 2022-12-17. (At that
time, the date of the most recent commit that was found in the
repository was 2022-12-16.) If you discover any rendering
problems in this HTML version of the page, or you believe there
is a better or more up-to-date source for the page, or you have
corrections or improvements to the information in this COLOPHON
(which is not part of the original manual page), send a mail to
man-pages@man7.org
systemd 252 SYSTEMD.LINK(5)
Pages that refer to this page: systemd.netdev(5), systemd.network(5), systemd.directives(7), systemd.index(7), systemd.net-naming-scheme(7), systemd.syntax(7), udev(7), systemd-networkd.service(8), systemd-network-generator.service(8), systemd-udevd.service(8)
|
HTML rendering created 2022-12-18 by Michael Kerrisk, author of The Linux Programming Interface, maintainer of the Linux man-pages project. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
|