Provided by: network-manager_1.46.0-1ubuntu2_amd64 
NAME
NetworkManager.conf - NetworkManager configuration file
SYNOPSIS
/etc/NetworkManager/NetworkManager.conf, /etc/NetworkManager/conf.d/name.conf,
/run/NetworkManager/conf.d/name.conf, /usr/lib/NetworkManager/conf.d/name.conf,
/var/lib/NetworkManager/NetworkManager-intern.conf
DESCRIPTION
NetworkManager.conf is the configuration file for NetworkManager. It is used to set up
various aspects of NetworkManager's behavior. The location of the main file and
configuration directories may be changed through use of the --config, --config-dir,
--system-config-dir, and --intern-config argument for NetworkManager, respectively.
If a default NetworkManager.conf is provided by your distribution's packages, you should
not modify it, since your changes may get overwritten by package updates. Instead, you can
add additional .conf files to the /etc/NetworkManager/conf.d directory. These will be read
in order, with later files overriding earlier ones. Packages might install further
configuration snippets to /usr/lib/NetworkManager/conf.d. This directory is parsed first,
even before NetworkManager.conf. Scripts can also put per-boot configuration into
/run/NetworkManager/conf.d. This directory is parsed second, also before
NetworkManager.conf. The loading of a file /run/NetworkManager/conf.d/name.conf can be
prevented by adding a file /etc/NetworkManager/conf.d/name.conf. Likewise, a file
/usr/lib/NetworkManager/conf.d/name.conf can be shadowed by putting a file of the same
name to either /etc/NetworkManager/conf.d or /run/NetworkManager/conf.d.
NetworkManager can overwrite certain user configuration options via D-Bus or other
internal operations. In this case it writes those changes to
/var/lib/NetworkManager/NetworkManager-intern.conf. This file is not intended to be
modified by the user, but it is read last and can shadow user configuration from
NetworkManager.conf.
Certain settings from the configuration can be reloaded at runtime either by sending
SIGHUP signal or via D-Bus' Reload call.
NetworkManager does not require any configuration in NetworkManager.conf. Depending on
your use case, you may remove all files to restore the default configuration (factory
reset). But note that your distribution or other packages may drop configuration snippets
for NetworkManager, such that they are part of the factory default.
FILE FORMAT
The configuration file format is so-called key file (sort of ini-style format). It
consists of sections (groups) of key-value pairs. Lines beginning with a '#' and blank
lines are considered comments. Sections are started by a header line containing the
section enclosed in '[' and ']', and ended implicitly by the start of the next section or
the end of the file. Each key-value pair must be contained in a section.
For keys that take a list of devices as their value, you can specify devices by their MAC
addresses or interface names, or "*" to specify all devices. See the section called
“Device List Format” below.
A simple configuration file looks like this:
[main]
plugins=keyfile
As an extension to the normal keyfile format, you can also append a value to a
previously-set list-valued key by doing:
plugins+=another-plugin
plugins-=remove-me
MAIN SECTION
plugins
Lists system settings plugin names separated by ','. These plugins are used to read
and write system-wide connection profiles. When multiple plugins are specified, the
connections are read from all listed plugins. When writing connections, the plugins
will be asked to save the connection in the order listed here; if the first plugin
cannot write out that connection type (or can't write out any connections) the next
plugin is tried, etc. If none of the plugins can save the connection, an error is
returned to the user.
The default value and the number of available plugins is distro-specific. See the
section called “PLUGINS” below for the available plugins. Note that NetworkManager's
native keyfile plugin is always appended to the end of this list (if it doesn't
already appear earlier in the list).
monitor-connection-files
This setting is deprecated and has no effect. Profiles from disk are never
automatically reloaded. Use for example nmcli connection (re)load for that.
auth-polkit
Whether the system uses PolicyKit for authorization. If true, non-root requests are
authorized using PolicyKit. Requests from root (user ID zero) are always granted
without asking PolicyKit. If false, all requests will be allowed and PolicyKit is not
used. If set to root-only PolicyKit is not used and all requests except root are
denied. The default value is true.
dhcp
This key sets up what DHCP client NetworkManager will use. Allowed values are
dhclient, dhcpcd, and internal. The dhclient and dhcpcd options require the indicated
clients to be installed. The internal option uses a built-in DHCP client which is not
currently as featureful as the external clients.
If this key is missing, it defaults to internal. If the chosen plugin is not
available, clients are looked for in this order: dhclient, dhcpcd, internal.
no-auto-default
Specify devices for which NetworkManager shouldn't create default wired connection
(Auto eth0). By default, NetworkManager creates a temporary wired connection for any
Ethernet device that is managed and doesn't have a connection configured. List a
device in this option to inhibit creating the default connection for the device. May
have the special value * to apply to all devices.
When the default wired connection is deleted or saved to a new persistent connection
by a plugin, the device is added to a list in the file
/var/lib/NetworkManager/no-auto-default.state to prevent creating the default
connection for that device again.
See the section called “Device List Format” for the syntax how to specify a device.
Example:
no-auto-default=00:22:68:5c:5d:c4,00:1e:65:ff:aa:ee
no-auto-default=eth0,eth1
no-auto-default=*
ignore-carrier
This setting is deprecated for the per-device setting ignore-carrier which overwrites
this setting if specified (See ignore-carrier). Otherwise, it is a list of matches to
specify for which device carrier should be ignored. See the section called “Device
List Format” for the syntax how to specify a device. Note that master types like bond,
bridge, and team ignore carrier by default. You can however revert that default using
the "except:" specifier (or better, use the per-device setting instead of the
deprecated setting).
assume-ipv6ll-only
Specify devices for which NetworkManager will try to generate a connection based on
initial configuration when the device only has an IPv6 link-local address.
See the section called “Device List Format” for the syntax how to specify a device.
configure-and-quit
This option is no longer useful to configure in NetworkManager.conf file. It can
however also be configured on the command line with the same values, where it has some
use.
When set to 'initrd', NetworkManager does not connect to D-Bus and quits after
configuring the network. This is an implementation detail how the NetworkManager
module of dracut can run NetworkManager. An alternative to this is having
NetworkManager as a systemd service with D-Bus in initrd.
The value 'true' is unsupported since version 1.36. Previously this was a mode where
NetworkManager would quit after configuring the network and run helper processes for
DHCP and SLAAC.
Otherwise, NetworkManager runs a system service with D-Bus and does not quit during
normal operation.
hostname-mode
Set the management mode of the hostname. This parameter will affect only the transient
hostname. If a valid static hostname is set, NetworkManager will skip the update of
the hostname despite the value of this option. An hostname empty or equal to
'localhost', 'localhost6', 'localhost.localdomain' or 'localhost6.localdomain' is
considered invalid.
default: NetworkManager will update the hostname with the one provided via DHCP or
reverse DNS lookup of the IP address on the connection with the default route or on
any connection with the property hostname.only-from-default set to 'false'.
Connections are considered in order of increasing value of the hostname.priority
property. In case multiple connections have the same priority, connections activated
earlier are considered first. If no hostname can be determined in such way, the
hostname will be updated to the last one set outside NetworkManager or to
'localhost.localdomain'.
dhcp: this is similar to 'default', with the difference that after trying to get the
DHCP hostname, reverse DNS lookup is not done. Note that selecting this option is
equivalent to setting the property 'hostname.from-dns-lookup' to 'false' globally for
all connections in NetworkManager.conf.
none: NetworkManager will not manage the transient hostname and will never set it.
dns
Set the DNS processing mode.
If the key is unspecified, default is used, unless /etc/resolv.conf is a symlink to
/run/systemd/resolve/stub-resolv.conf, /run/systemd/resolve/resolv.conf,
/lib/systemd/resolv.conf or /usr/lib/systemd/resolv.conf. In that case,
systemd-resolved is chosen automatically.
default: NetworkManager will update /etc/resolv.conf to reflect the nameservers
provided by currently active connections. The rc-manager setting (below) controls how
this is done.
dnsmasq: NetworkManager will run dnsmasq as a local caching nameserver, using
"Conditional Forwarding" if you are connected to a VPN, and then update resolv.conf to
point to the local nameserver. It is possible to pass custom options to the dnsmasq
instance by adding them to files in the "/etc/NetworkManager/dnsmasq.d/" directory.
Note that when multiple upstream servers are available, dnsmasq will initially contact
them in parallel and then use the fastest to respond, probing again other servers
after some time. This behavior can be modified passing the 'all-servers' or
'strict-order' options to dnsmasq (see the manual page for more details).
systemd-resolved: NetworkManager will push the DNS configuration to systemd-resolved
none: NetworkManager will not modify resolv.conf. This implies rc-manager unmanaged
Note that the plugins dnsmasq and systemd-resolved are caching local nameservers.
Hence, when NetworkManager writes /run/NetworkManager/resolv.conf and /etc/resolv.conf
(according to rc-manager setting below), the name server there will be localhost only.
NetworkManager also writes a file /run/NetworkManager/no-stub-resolv.conf that
contains the original name servers pushed to the DNS plugin.
When using dnsmasq and systemd-resolved, per-connection added dns servers will always
be queried using the device the connection has been activated on.
rc-manager
Set the resolv.conf management mode. This option is about how NetworkManager writes to
/etc/resolv.conf, if at all. The default value depends on NetworkManager build
options, and this version of NetworkManager was build with a default of "". Regardless
of this setting, NetworkManager will always write its version of resolv.conf to its
runtime state directory as /run/NetworkManager/resolv.conf.
If you configure dns=none or make /etc/resolv.conf immutable with chattr +i,
NetworkManager will ignore this setting and always choose unmanaged (below).
auto: if systemd-resolved plugin is configured via the dns setting or if it gets
detected as main DNS plugin, NetworkManager will update systemd-resolved without
touching /etc/resolv.conf. Alternatively, if resolvconf or netconfig are enabled at
compile time and the respective binary is found, NetworkManager will automatically use
it. Note that if you install or uninstall these binaries, you need to reload the
rc-manager setting with SIGHUP or systemctl reload NetworkManager. As last fallback it
uses the symlink option (see next).
symlink: If /etc/resolv.conf is a regular file or does not exist, NetworkManager will
write the file directly. If /etc/resolv.conf is instead a symlink, NetworkManager will
leave it alone. Unless the symlink points to the internal file
/run/NetworkManager/resolv.conf, in which case the symlink will be updated to emit an
inotify notification. This allows the user to conveniently instruct NetworkManager not
to manage /etc/resolv.conf by replacing it with a symlink.
file: NetworkManager will write /etc/resolv.conf as regular file. If it finds a
symlink to an existing target, it will follow the symlink and update the target
instead. In no case will an existing symlink be replaced by a file. Note that older
versions of NetworkManager behaved differently and would replace dangling symlinks
with a plain file.
resolvconf: NetworkManager will run resolvconf to update the DNS configuration.
netconfig: NetworkManager will run netconfig to update the DNS configuration.
unmanaged: don't touch /etc/resolv.conf.
none: deprecated alias for symlink.
systemd-resolved
Additionally, send the connection DNS configuration to systemd-resolved. Defaults to
"true".
Note that this setting has no effect if the main dns plugin is already
systemd-resolved. It is complementary to the dns setting to configure systemd-resolved
alongside the main plugin.
If systemd-resolved is enabled, either via this setting or the main DNS plugin, the
connectivity check resolves the hostname per-device.
debug
Comma separated list of options to aid debugging. This value will be combined with the
environment variable NM_DEBUG. Currently, the following values are supported:
RLIMIT_CORE: set ulimit -c unlimited to write out core dumps. Beware, that a core dump
can contain sensitive information such as passwords or configuration settings.
fatal-warnings: set g_log_set_always_fatal() to core dump on warning messages from
glib. This is equivalent to the --g-fatal-warnings command line option.
autoconnect-retries-default
The number of times a connection activation should be automatically tried before
switching to another one. This value applies only to connections that can auto-connect
and have a connection.autoconnect-retries property set to -1. If not specified,
connections will be tried 4 times. Setting this value to 1 means to try activation
once, without retry.
firewall-backend
The firewall backend for configuring masquerading with shared mode. Set to either
iptables, nftables or none. iptables and nftables require iptables and nft
application, respectively. none means to skip firewall configuration if the users
wish to manage firewall themselves. If unspecified, it will be auto detected.
iwd-config-path
If the value is "auto" (the default), IWD is queried for its current state directory
when it appears on D-Bus -- the directory where IWD keeps its network configuration
files -- usually /var/lib/iwd. NetworkManager will then attempt to write copies of new
or modified Wi-Fi connection profiles, converted into the IWD format, into this
directory thus making IWD connection properties editable. NM will overwrite existing
files without preserving their contents.
The path can also be overriden by pointing to a specific existing and writable
directory. On the other hand setting this to an empty string or any other value
disables the profile conversion mechanism.
This mechanism allows editing connection profile settings such as the 802.1x
configuration using NetworkManager clients. Without it such changes have no effect in
IWD.
migrate-ifcfg-rh
Whether NetworkManager tries to automatically convert any connection profile stored in
ifcfg-rh format to the keyfile format. Support for ifcfg-rh is deprecated and will be
eventually removed. If enabled, the migration is performed at every startup of the
daemon. The default value is false.
KEYFILE SECTION
This section contains keyfile-plugin-specific options, and is normally only used when you
are not using any other distro-specific plugin.
hostname
This key is deprecated and has no effect since the hostname is now stored in
/etc/hostname or other system configuration files according to build options.
path
The location where keyfiles are read and stored. This defaults to
"/etc/NetworkManager/system-connections".
rename
NetworkManager automatically chooses a filename when storing a new profile to disk.
That name depends on the profile's name (connection.id). When updating a profile's
name, the file is not renamed to not break scripts that rely on the filename for the
profile. By setting this option to "true", NetworkManager renames the keyfile on
update of the profile, to follow the profile's name. This defaults to "false".
unmanaged-devices
Set devices that should be ignored by NetworkManager.
A device unmanaged due to this option is strictly unmanaged and cannot be overruled by
using the API like nmcli device set $IFNAME managed yes. Also, a device that is
unmanaged for other reasons, like an udev rule, cannot be made managed with this
option (e.g. by using an except: specifier). These two points make it different from
the device*.managed option which for that reason may be a better choice.
See the section called “Device List Format” for the syntax on how to specify a device.
Example:
unmanaged-devices=interface-name:em4
unmanaged-devices=mac:00:22:68:1c:59:b1;mac:00:1E:65:30:D1:C4;interface-name:eth2
IFUPDOWN SECTION
This section contains ifupdown-specific options and thus only has effect when using the
ifupdown plugin.
managed
If set to true, then interfaces listed in /etc/network/interfaces are managed by
NetworkManager. If set to false, then any interface listed in /etc/network/interfaces
will be ignored by NetworkManager. Remember that NetworkManager controls the default
route, so because the interface is ignored, NetworkManager may assign the default
route to some other interface.
The default value is false.
LOGGING SECTION
This section controls NetworkManager's logging. Logging is very important to understand
what NetworkManager is doing. When you report a bug, do not unnecessarily filter or limit
the log file. Just enable level=TRACE and domains=ALL to collect everything.
The recommended way for enabling logging is with a file
/etc/NetworkManager/conf.d/95-logging.conf that contains
[logging]
level=TRACE
domains=ALL
and restart the daemon with systemctl restart NetworkManager. Then reproduce the problem.
You can find the logs in syslog (for example journalctl, or journalctl -u NetworkManager
to show only logs from NetworkManager).
Any settings here are overridden by the --log-level and --log-domains command-line
options. Logging can also be reconfigured at runtime with nmcli general logging level
"$LEVEL" domains "$DOMAINS". However, often it is interesting to get a complete log from
the start. Especially, when debugging an issue, enable debug logging in
NetworkManager.conf and restart the service to enable verbose logging early on.
By setting nm.debug on the kernel command line (either from
/run/NetworkManager/proc-cmdline or /proc/cmdline), debug logging is enabled. This
overrides both the command-line options and the settings from NetworkManager.conf.
NetworkManager's logging aims not to contain private sensitive data and you should be fine
sharing the debug logs. Still, there will be IP addresses and your network setup, if you
consider that private then review the log before sharing. However, try not to mangle the
logfile in a way that distorts the meaning too much.
NetworkManager uses syslog or systemd-journald, depending on configuration. In any case,
debug logs are verbose and might be rate limited or filtered by the logging daemon. For
systemd-journald, see RateLimitIntervalSec and RateLimitBurst in journald.conf manual for
how to disable that.
level
The default logging verbosity level. One of OFF, ERR, WARN, INFO, DEBUG, TRACE, in
order of verbosity.
OFF disables all logging. INFO is the default verbosity for regular operation. TRACE
is for debugging.
The other levels are in most cases not useful. For example, DEBUG is between TRACE and
INFO, but it's too verbose for regular operation and lacks possibly interesting
messages for debugging. Almost always, when debugging an issue or reporting a bug,
collect full level TRACE logs to get the full picture.
domains
Filter the messages by their topic. When debugging an issue, it's better to collect
all logs (ALL domain) upfront. The unnecessary parts can always be ignored later.
In the uncommon case to tune out certain topics, the following log domains are
available: PLATFORM, RFKILL, ETHER, WIFI, BT, MB, DHCP4, DHCP6, PPP, WIFI_SCAN, IP4,
IP6, AUTOIP4, DNS, VPN, SHARING, SUPPLICANT, AGENTS, SETTINGS, SUSPEND, CORE, DEVICE,
OLPC, WIMAX, INFINIBAND, FIREWALL, ADSL, BOND, VLAN, BRIDGE, DBUS_PROPS, TEAM,
CONCHECK, DCB, DISPATCH, AUDIT, SYSTEMD, VPN_PLUGIN, PROXY.
In addition, these special domains can be used: NONE, ALL, DEFAULT, DHCP, IP.
You can specify per-domain log level overrides by adding a colon and a log level to
any domain. E.g., "WIFI:DEBUG,WIFI_SCAN:OFF". Another example is ALL,VPN_PLUGIN:TRACE
to enable all the logging there is (see about VPN_PLUGIN below).
Domain descriptions:
PLATFORM : OS (platform) operations
RFKILL : RFKill subsystem operations
ETHER : Ethernet device operations
WIFI : Wi-Fi device operations
BT : Bluetooth operations
MB : Mobile broadband operations
DHCP4 : DHCP for IPv4
DHCP6 : DHCP for IPv6
PPP : Point-to-point protocol operations
WIFI_SCAN : Wi-Fi scanning operations
IP4 : IPv4-related operations
IP6 : IPv6-related operations
AUTOIP4 : AutoIP operations
DNS : Domain Name System related operations
VPN : Virtual Private Network connections and operations
SHARING : Connection sharing. With TRACE level log queries for dnsmasq
instance
SUPPLICANT : WPA supplicant related operations
AGENTS : Secret agents operations and communication
SETTINGS : Settings/config service operations
SUSPEND : Suspend/resume
CORE : Core daemon and policy operations
DEVICE : Activation and general interface operations
OLPC : OLPC Mesh device operations
WIMAX : WiMAX device operations
INFINIBAND : InfiniBand device operations
FIREWALL : FirewallD related operations
ADSL : ADSL device operations
BOND : Bonding operations
VLAN : VLAN operations
BRIDGE : Bridging operations
DBUS_PROPS : D-Bus property changes
TEAM : Teaming operations
CONCHECK : Connectivity check
DCB : Data Center Bridging (DCB) operations
DISPATCH : Dispatcher scripts
AUDIT : Audit records
SYSTEMD : Messages from internal libsystemd
VPN_PLUGIN : logging messages from VPN plugins
PROXY : logging messages for proxy handling
NONE : when given by itself logging is disabled
ALL : all log domains
DEFAULT : default log domains
DHCP : shortcut for "DHCP4,DHCP6"
IP : shortcut for "IP4,IP6"
HW : deprecated alias for "PLATFORM"
In general, the logfile should not contain passwords or private data. However, you are
always advised to check the file before posting it online or attaching to a bug
report. VPN_PLUGIN is special as it might reveal private information of the VPN
plugins with verbose levels. Therefore this domain will be excluded when setting ALL
or DEFAULT to more verbose levels then INFO.
backend
The logging backend. Supported values are "syslog" and "journal". When NetworkManager
is started with "--debug" in addition all messages will be printed to stderr. If
unspecified, the default is "journal".
audit
Whether the audit records are delivered to auditd, the audit daemon. If false, audit
records will be sent only to the NetworkManager logging system. If set to true, they
will be also sent to auditd. The default value is true.
CONNECTION SECTION
Specify default values for connections.
Such default values are only consulted if the corresponding per-connection property
explicitly allows for that. That means, all these properties correspond to a property of
the connection profile (for example connection.mud-url). Only if the per-profile property
is set to a special value that indicates to use the default, the default value from
NetworkManager.conf is consulted. It depends on the property, which is the special value
that indicates fallback to the default, but it usually is something like empty, unset
values or special numeric values like 0 or -1. That means the effectively used value can
first always be configured for each profile, and these default values only matter if the
per-profile values explicitly indicates to use the default from NetworkManager.conf.
Example:
[connection]
ipv6.ip6-privacy=0
Supported Properties
Not all properties can be overwritten, only the following properties are supported to have
their default values configured (see nm-settings-nmcli(5) for details).
802-1x.auth-timeout
cdma.mtu
connection.auth-retries
If left unspecified, the default value is 3 tries before failing the connection.
connection.autoconnect-slaves
connection.mud-url
If unspecified, MUD URL defaults to "none".
connection.lldp
connection.llmnr
If unspecified, the ultimate default values depends on the DNS plugin. With
systemd-resolved the default currently is "yes" (2) and for all other plugins "no"
(0).
connection.mdns
If unspecified, the ultimate default values depends on the DNS plugin. With
systemd-resolved the default currently is "no" (0) and for all other plugins also "no"
(0).
connection.mptcp-flags
If unspecified, the fallback is 0x22 ("enabled,subflow"). Note that if sysctl
/proc/sys/net/mptcp/enabled is disabled, NetworkManager will still not configure
endpoints.
connection.dns-over-tls
If unspecified, the ultimate default values depends on the DNS plugin. With
systemd-resolved the default currently is global setting and for all other plugins
"no" (0).
connection.stable-id
ethernet.cloned-mac-address
If left unspecified, it defaults to "preserve".
ethernet.generate-mac-address-mask
ethernet.mtu
If configured explicitly to 0, the MTU is not reconfigured during device activation
unless it is required due to IPv6 constraints. If left unspecified, a DHCP/IPv6 SLAAC
provided value is used or the MTU is not reconfigured during activation.
ethernet.wake-on-lan
gsm.mtu
hostname.from-dhcp
hostname.from-dns-lookup
hostname.only-from-default
hostname.priority
infiniband.mtu
If configured explicitly to 0, the MTU is not reconfigured during device activation
unless it is required due to IPv6 constraints. If left unspecified, a DHCP/IPv6 SLAAC
provided value is used or the MTU is left unspecified on activation.
ip-tunnel.mtu
If configured explicitly to 0, the MTU is not reconfigured during device activation
unless it is required due to IPv6 constraints. If left unspecified, a DHCP/IPv6 SLAAC
provided value is used or a default of 1500.
ipv4.dad-timeout
ipv4.dhcp-client-id
ipv4.dhcp-dscp
ipv4.dhcp-iaid
If left unspecified, it defaults to "ifname".
ipv4.dhcp-hostname-flags
If left unspecified, the value 3 (fqdn-encoded,fqdn-serv-update) is used.
ipv4.dhcp-timeout
If left unspecified, the default value for the interface type is used.
ipv4.dhcp-vendor-class-identifier
If left unspecified, the default is to not send the DHCP option to the server.
ipv4.dns-priority
If unspecified or zero, use 50 for VPN profiles and 100 for other profiles.
ipv4.required-timeout
ipv4.link-local
If left unspecified, fallback to "auto" which makes it dependent on "ipv4.method"
setting.
ipv4.route-metric
ipv4.route-table
If left unspecified, routes are only added to the main table. Note that this is
different from explicitly selecting the main table 254, because of how NetworkManager
removes extraneous routes from the tables.
ipv6.addr-gen-mode
If the per-profile setting is either "default" or "default-or-eui64", the global
default is used. If the default is unspecified, the fallback value is either
"stable-privacy" or "eui64", depending on whether the per-profile setting is "default"
or "default-or-eui64, respectively.
ipv6.ra-timeout
If left unspecified, the default value depends on the sysctl solicitation settings.
ipv6.dhcp-duid
If left unspecified, it defaults to "lease".
ipv6.dhcp-iaid
If left unspecified, it defaults to "ifname".
ipv6.dhcp-hostname-flags
If left unspecified, the value 1 (fqdn-serv-update) is used.
ipv6.dhcp-timeout
If left unspecified, the default value for the interface type is used.
ipv6.dns-priority
If unspecified or zero, use 50 for VPN profiles and 100 for other profiles.
ipv6.ip6-privacy
If ipv6.ip6-privacy is unset, use the content of
"/proc/sys/net/ipv6/conf/default/use_tempaddr" as last fallback.
ipv6.required-timeout
ipv6.route-metric
ipv6.route-table
If left unspecified, routes are only added to the main table. Note that this is
different from explicitly selecting the main table 254, because of how NetworkManager
removes extraneous routes from the tables.
loopback.mtu
If configured explicitly to 0, the MTU is not reconfigured during device activation
unless it is required due to IPv6 constraints. If left unspecified, a DHCP/IPv6 SLAAC
provided value is used or the MTU is left unspecified on activation.
macsec.offload
sriov.autoprobe-drivers
If left unspecified, drivers are autoprobed when the SR-IOV VF gets created.
vpn.timeout
If left unspecified, default value of 60 seconds is used.
wifi.ap-isolation
If left unspecified, AP isolation is disabled.
wifi.cloned-mac-address
If left unspecified, it defaults to "preserve".
wifi.generate-mac-address-mask
wifi.mac-address-randomization
If left unspecified, MAC address randomization is disabled. This setting is deprecated
for wifi.cloned-mac-address.
wifi.mtu
If configured explicitly to 0, the MTU is not reconfigured during device activation
unless it is required due to IPv6 constraints. If left unspecified, a DHCP/IPv6 SLAAC
provided value is used or a default of 1500.
wifi.powersave
If left unspecified, the default value "ignore" will be used.
wifi-sec.pmf
If left unspecified, the default value "optional" will be used.
wifi-sec.fils
If left unspecified, the default value "optional" will be used.
wifi.wake-on-wlan
wireguard.mtu
Sections
You can configure multiple connection sections, by having different sections with a name
that all start with "connection". Example:
[connection]
ipv6.ip6-privacy=0
connection.autoconnect-slaves=1
vpn.timeout=120
[connection-wifi-wlan0]
match-device=interface-name:wlan0
ipv4.route-metric=50
[connection-wifi-other]
match-device=type:wifi
ipv4.route-metric=55
ipv6.ip6-privacy=1
The sections within one file are considered in order of appearance, with the exception
that the [connection] section is always considered last. In the example above, this order
is [connection-wifi-wlan0], [connection-wlan-other], and [connection]. When checking for a
default configuration value, the sections are searched until the requested value is found.
In the example above, "ipv4.route-metric" for wlan0 interface is set to 50, and for all
other Wi-Fi typed interfaces to 55. Also, Wi-Fi devices would have IPv6 private addresses
enabled by default, but other devices would have it disabled. Note that also "wlan0" gets
"ipv6.ip6-privacy=1", because although the section "[connection-wifi-wlan0]" matches the
device, it does not contain that property and the search continues.
When having different sections in multiple files, sections from files that are read later
have higher priority. So within one file the priority of the sections is top-to-bottom.
Across multiple files later definitions take precedence.
The following properties further control how a connection section applies.
match-device
An optional device spec that restricts when the section applies. See the section
called “Device List Format” for the possible values.
stop-match
An optional boolean value which defaults to no. If the section matches (based on
match-device), further sections will not be considered even if the property in
question is not present. In the example above, if [connection-wifi-wlan0] would have
stop-match set to yes, the device wlan0 would have ipv6.ip6-privacy property
unspecified. That is, the search for the property would not continue in the connection
sections [connection-wifi-other] or [connection].
DEVICE SECTION
Contains per-device persistent configuration.
Example:
[device]
match-device=interface-name:eth3
managed=1
Supported Properties
The following properties can be configured per-device.
managed
Whether the device is managed or not. A device can be marked as managed via udev rules
(ENV{NM_UNMANAGED}), or via setting plugins (keyfile.unmanaged-devices). This is yet
another way. Note that this configuration can be overruled at runtime via D-Bus. Also,
it has higher priority then udev rules.
carrier-wait-timeout
Specify the timeout for waiting for carrier in milliseconds. The default is 6000
milliseconds. This setting exists because certain drivers/hardware can take a long
time to detect whether the cable is plugged in.
When the device loses carrier, NetworkManager does not react immediately. Instead, it
waits for this timeout before considering the link lost.
Also, on startup, NetworkManager considers the device as busy for this time, as long
as the device has no carrier. This delays startup-complete signal and
NetworkManager-wait-online. Configuring this too high means to block
NetworkManager-wait-online longer than necessary when booting with cable unplugged.
Configuring it too low, means that NetworkManager will declare startup-complete too
soon, although carrier is about to come and auto-activation to kick in. Note that if a
profile only has static IP configuration or Layer 3 configuration disabled, then it
can already autoconnect without carrier on the device. Once such a profile reaches
full activated state, startup-complete is considered as reached even if the device has
no carrier yet.
ignore-carrier
Specify devices for which NetworkManager will (partially) ignore the carrier state.
Normally, for device types that support carrier-detect, such as Ethernet and
InfiniBand, NetworkManager will only allow a connection to be activated on the device
if carrier is present (ie, a cable is plugged in), and it will deactivate the device
if carrier drops for more than a few seconds.
A device with carrier ignored will allow activating connections on that device even
when it does not have carrier, provided that the connection uses only
statically-configured IP addresses. Additionally, it will allow any active connection
(whether static or dynamic) to remain active on the device when carrier is lost.
Note that the "carrier" property of NMDevices and device D-Bus interfaces will still
reflect the actual device state; it's just that NetworkManager will not make use of
that information.
Master types like bond, bridge and team ignore carrier by default, while other device
types react on carrier changes by default.
This setting overwrites the deprecated main.ignore-carrier setting above.
keep-configuration
On startup, NetworkManager tries to not interfere with interfaces that are already
configured. It does so by generating a in-memory connection based on the interface
current configuration.
If this generated connection matches one of the existing persistent connections, the
persistent connection gets activated. If there is no match, the generated connection
gets activated as "external", which means that the connection is considered as active,
but NetworkManager doesn't actually touch the interface.
It is possible to disable this behavior by setting keep-configuration to no. In this
way, on startup NetworkManager always tries to activate the most suitable persistent
connection (the one with highest autoconnect-priority or, in case of a tie, the one
activated most recently).
Note that when NetworkManager gets restarted, it stores the previous state in
/run/NetworkManager; in particular it saves the UUID of the connection that was
previously active so that it can be activated again after the restart. Therefore,
keep-configuration does not have any effect on service restart.
allowed-connections
A list of connections that can be activated on the device. See the section called
“Connection List Format” for the syntax to specify a connection. If this option is not
specified, all connections can be potentially activated on the device, provided that
the connection type and other settings match.
A notable use case for this is to filter which connections can be activated based on
how they were created; see the origin keyword in the section called “Connection List
Format”.
wifi.scan-rand-mac-address
Configures MAC address randomization of a Wi-Fi device during scanning. This defaults
to yes in which case a random, locally-administered MAC address will be used. The
setting wifi.scan-generate-mac-address-mask allows to influence the generated MAC
address to use certain vendor OUIs. If disabled, the MAC address during scanning is
left unchanged to whatever is configured. For the configured MAC address while the
device is associated, see instead the per-connection setting wifi.cloned-mac-address.
wifi.backend
Specify the Wi-Fi backend used for the device. Currently, supported are wpa_supplicant
and iwd (experimental). If unspecified, the default is "wpa_supplicant".
wifi.scan-generate-mac-address-mask
Like the per-connection settings ethernet.generate-mac-address-mask and
wifi.generate-mac-address-mask, this allows to configure the generated MAC addresses
during scanning. See nm-settings-nmcli(5) for details.
wifi.iwd.autoconnect
If wifi.backend is iwd, setting this to false forces IWD's autoconnect mechanism to be
disabled for this device and connections will only be initiated by NetworkManager
whether commanded by a client or automatically. Leaving it true (default) stops
NetworkManager from automatically initiating connections and allows IWD to use its
network ranking and scanning logic to decide the best networks to autoconnect to next.
Connections' autoconnect-priority, autoconnect-retries settings will be ignored. Other
settings like permissions or multi-connect may interfere with IWD connection attempts.
sriov-num-vfs
Specify the number of virtual functions (VF) to enable for a PCI physical device that
supports single-root I/O virtualization (SR-IOV).
Sections
The [device] section works the same as the [connection] section. That is, multiple
sections that all start with the prefix "device" can be specified. The settings
"match-device" and "stop-match" are available to match a device section on a device. The
order of multiple sections is also top-down within the file and later files overwrite
previous settings. See “Sections” under the section called “CONNECTION SECTION” for
details.
CONNECTIVITY SECTION
This section controls NetworkManager's optional connectivity checking functionality. This
allows NetworkManager to detect whether or not the system can actually access the internet
or whether it is behind a captive portal.
Connectivity checking serves two purposes. For one, it exposes a connectivity state on
D-Bus, which other applications may use. For example, Gnome's portal helper uses this as
signal to show a captive portal login page. The other use is that default-route of devices
without global connectivity get a penalty of +20000 to the route-metric. This has the
purpose to give a better default-route to devices that have global connectivity. For
example, when being connected to WWAN and to a Wi-Fi network which is behind a captive
portal, WWAN still gets preferred until login.
Note that your distribution might set /proc/sys/net/ipv4/conf/*/rp_filter to strict
filtering. That works badly with per-device connectivity checking, which uses
SO_BINDDEVICE to send requests on all devices. A strict rp_filter setting will reject any
response and the connectivity check on all but the best route will fail.
enabled
Whether connectivity check is enabled. Note that to enable connectivity check, a valid
uri must also be configured. The value defaults to true, but since the uri is unset by
default, connectivity check may be disabled. The main purpose of this option is to
have a single flag to disable connectivity check. Note that this setting can also be
set via D-Bus API at runtime. In that case, the value gets stored in
/var/lib/NetworkManager/NetworkManager-intern.conf file.
uri
The URI of a web page to periodically request when connectivity is being checked. This
page should return the header "X-NetworkManager-Status" with a value of "online".
Alternatively, its body content should be set to "NetworkManager is online". The body
content check can be controlled by the response option. If this option is blank or
missing, connectivity checking is disabled.
interval
Specified in seconds; controls how often connectivity is checked when a network
connection exists. If set to 0 connectivity checking is disabled. If missing, the
default is 300 seconds.
response
If set, controls what body content NetworkManager checks for when requesting the URI
for connectivity checking. Note that this only compares that the HTTP response starts
with the specifid text, it does not compare the exact string. This behavior might
change in the future, so avoid relying on it. If missing, the response defaults to
"NetworkManager is online". If set to empty, the HTTP server is expected to answer
with status code 204 or send no data.
GLOBAL-DNS SECTION
This section specifies DNS settings that are applied globally, in addition to
connection-specific ones.
searches
A list of search domains to be used during hostname lookup.
options
A list of options to be passed to the hostname resolver.
GLOBAL-DNS-DOMAIN SECTIONS
Sections with a name starting with the "global-dns-domain-" prefix allow to define global
DNS configuration for specific domains. The part of section name after
"global-dns-domain-" specifies the domain name a section applies to (for example, a
section could be named "global-dns-domain-foobar.com"). More specific domains have the
precedence over less specific ones and the default domain is represented by the wildcard
"*". To be valid, global DNS domains must include a section for the default domain "*".
When the global DNS domains are valid, the name servers and domains defined globally
override the ones from active connections.
servers
A list of addresses of DNS servers to be used for the given domain.
options
A list of domain-specific DNS options. Not used at the moment.
.CONFIG SECTIONS
This is a special section that contains options which apply to the configuration file that
contains the option.
enable
Defaults to "true". If "false", the configuration file will be skipped during loading.
Note that the main configuration file NetworkManager.conf cannot be disabled.
# always skip loading the config file
[.config]
enable=false
You can also match against the version of NetworkManager. For example the following
are valid configurations:
# only load on version 1.0.6
[.config]
enable=nm-version:1.0.6
# load on all versions 1.0.x, but not 1.2.x
[.config]
enable=nm-version:1.0
# only load on versions >= 1.1.6. This does not match
# with version 1.2.0 or 1.4.4. Only the last digit is considered.
[.config]
enable=nm-version-min:1.1.6
# only load on versions >= 1.2. Contrary to the previous
# example, this also matches with 1.2.0, 1.2.10, 1.4.4, etc.
[.config]
enable=nm-version-min:1.2
# Match against the maximum allowed version. The example matches
# versions 1.2.0, 1.2.2, 1.2.4. Again, only the last version digit
# is allowed to be smaller. So this would not match on 1.1.10.
[.config]
enable=nm-version-max:1.2.6
You can also match against the value of the environment variable NM_CONFIG_ENABLE_TAG,
like:
# only load the file when running NetworkManager with
# environment variable "NM_CONFIG_ENABLE_TAG=TAG1"
[.config]
enable=env:TAG1
More then one match can be specified. The configuration will be enabled if one of the
predicates matches ("or"). The special prefix "except:" can be used to negate the
match. Note that if one except-predicate matches, the entire configuration will be
disabled. In other words, a except predicate always wins over other predicates. If the
setting only consists of "except:" matches and none of the negative conditions are
satisfied, the configuration is still enabled.
# enable the configuration either when the environment variable
# is present or the version is at least 1.2.0.
[.config]
enable=env:TAG2,nm-version-min:1.2
# enable the configuration for version >= 1.2.0, but disable
# it when the environment variable is set to "TAG3"
[.config]
enable=except:env:TAG3,nm-version-min:1.2
# enable the configuration on >= 1.3, >= 1.2.6, and >= 1.0.16.
# Useful if a certain feature is only present since those releases.
[.config]
enable=nm-version-min:1.3,nm-version-min:1.2.6,nm-version-min:1.0.16
PLUGINS
Settings plugins for reading and writing connection profiles. The number of available
plugins is distribution specific.
keyfile
The keyfile plugin is the generic plugin that supports all the connection types and
capabilities that NetworkManager has. It writes files out in an .ini-style format in
/etc/NetworkManager/system-connections. See nm-settings-keyfile(5) for details about
the file format.
The stored connection file may contain passwords, secrets and private keys in plain
text, so it will be made readable only to root, and the plugin will ignore files that
are readable or writable by any user or group other than root. See "Secret flag types"
in nm-settings-nmcli(5) for how to avoid storing passwords in plain text.
This plugin is always active, and will automatically be used to store any connections
that aren't supported by any other active plugin.
ifcfg-rh
This plugin is now deprecated; it can be used on the Fedora and Red Hat Enterprise
Linux distributions to read and write configuration from the standard
/etc/sysconfig/network-scripts/ifcfg-* files. It currently supports reading Ethernet,
Wi-Fi, InfiniBand, VLAN, Bond, Bridge, and Team connections. Enabling ifcfg-rh
implicitly enables ibft plugin, if it is available. This can be disabled by adding
no-ibft. See /usr/share/doc/initscripts/sysconfig.txt and nm-settings-ifcfg-rh(5) for
more information about the ifcfg file format.
ifupdown
This plugin is used on the Debian and Ubuntu distributions, and reads Ethernet and
Wi-Fi connections from /etc/network/interfaces.
This plugin is read-only; any connections (of any type) added from within
NetworkManager when you are using this plugin will be saved using the keyfile plugin
instead.
ibft, no-ibft
These plugins are deprecated and their selection has no effect. This is now handled by
nm-initrd-generator.
ifcfg-suse, ifnet
These plugins are deprecated and their selection has no effect. The keyfile plugin
should be used instead.
APPENDIX
Device List Format
The configuration options main.no-auto-default, main.ignore-carrier,
keyfile.unmanaged-devices, connection*.match-device and device*.match-device select
devices based on a list of matchings. Devices can be specified using the following format:
*
Matches every device.
IFNAME
Case sensitive match of interface name of the device. Globbing is not supported.
HWADDR
Match the permanent MAC address of the device. Globbing is not supported
interface-name:IFNAME, interface-name:~IFNAME
Case sensitive match of interface name of the device. Simple globbing is supported
with * and ?. Ranges and escaping is not supported.
interface-name:=IFNAME
Case sensitive match of interface name of the device. Globbing is disabled and IFNAME
is taken literally.
mac:HWADDR
Match the permanent MAC address of the device. Globbing is not supported
s390-subchannels:HWADDR
Match the device based on the subchannel address. Globbing is not supported
type:TYPE
Match the device type. Valid type names are as reported by "nmcli -f GENERAL.TYPE
device show". Globbing is not supported.
driver:DRIVER
Match the device driver as reported by "nmcli -f GENERAL.DRIVER,GENERAL.DRIVER-VERSION
device show". "DRIVER" must match the driver name exactly and does not support
globbing. Optionally, a driver version may be specified separated by '/'. Globbing is
supported for the version.
dhcp-plugin:DHCP
Match the configured DHCP plugin "main.dhcp".
except:SPEC
Negative match of a device. SPEC must be explicitly qualified with a prefix such as
interface-name:. A negative match has higher priority then the positive matches above.
If there is a list consisting only of negative matches, the behavior is the same as if
there is also match-all. That means, if none of all the negative matches is satisfied,
the overall result is still a positive match. That means, "except:interface-name:eth0"
is the same as "*,except:interface-name:eth0".
SPEC[,;]SPEC
Multiple specs can be concatenated with commas or semicolons. The order does not
matter as matches are either inclusive or negative (except:), with negative matches
having higher priority.
Backslash is supported to escape the separators ';' and ',', and to express special
characters such as newline ('\n'), tabulator ('\t'), whitespace ('\s') and backslash
('\\'). The globbing of interface names cannot be escaped. Whitespace is not a
separator but will be trimmed between two specs (unless escaped as '\s').
Example:
interface-name:em4
mac:00:22:68:1c:59:b1;mac:00:1E:65:30:D1:C4;interface-name:eth2
interface-name:vboxnet*,except:interface-name:vboxnet2
*,except:mac:00:22:68:1c:59:b1
Connection List Format
Connections can be specified using the following format:
*
Matches every connection.
uuid:UUID
Match the connection by UUID, for example "uuid:83037490-1d17-4986-a397-01f1db3a7fc2"
id=ID
Match the connection by name.
origin:ORIGIN
Match the connection by origin, stored in the org.freedesktop.NetworkManager.origin
tag of the user setting. For example, use "except:origin:nm-initrd-generator" to
forbid activation of connections created by the initrd generator.
except:SPEC
Negative match of a connection. A negative match has higher priority then the positive
matches above.
If there is a list consisting only of negative matches, the behavior is the same as if
there is also match-all. That means, if none of all the negative matches is satisfied,
the overall result is still a positive match.
SPEC[,;]SPEC
Multiple specs can be concatenated with commas or semicolons. The order does not
matter as matches are either inclusive or negative (except:), with negative matches
having higher priority.
Backslash is supported to escape the separators ';' and ',', and to express special
characters such as newline ('\n'), tabulator ('\t'), whitespace ('\s') and backslash
('\\'). Whitespace is not a separator but will be trimmed between two specs (unless
escaped as '\s').
SEE ALSO
NetworkManager(8), nmcli(1), nmcli-examples(7), nm-online(1), nm-settings-nmcli(5), nm-
applet(1), nm-connection-editor(1)