ipv4: NetworkManager Reference Manual

## ipv4 ipv4 — IPv4 Settings |

## Properties

Table 69.

Key Name | Value Type | Default Value | Value Description
--- | --- | --- | ---
    address-data
    array of vardict
| Array of IPv4 addresses. Each address dictionary contains at least 'address' and 'prefix' entries, containing the IP address as a string, and the prefix length as a uint32. Additional attributes may also exist on some addresses.
    addresses
    array of array of uint32
    []
| Deprecated in favor of the 'address-data' and 'gateway' properties, but this can be used for backward-compatibility with older daemons. Note that if you send this property the daemon will ignore 'address-data' and 'gateway'. Array of IPv4 address structures. Each IPv4 address structure is composed of 3 32-bit values; the first being the IPv4 address (network byte order), the second the prefix (1 - 32), and last the IPv4 gateway (network byte order). The gateway may be left as 0 if no gateway exists for that subnet.
    dad-timeout
    int32
    -1
| Timeout in milliseconds used to check for the presence of duplicate IP addresses on the network. If an address conflict is detected, the activation will fail. A zero value means that no duplicate address detection is performed, -1 means the default value (either configuration ipvx.dad-timeout override or 3 seconds). A value greater than zero is a timeout in milliseconds.
    dhcp-client-id
    string
| A string sent to the DHCP server to identify the local machine which the DHCP server may use to customize the DHCP lease and options. When the property is a hex string ('aa:bb:cc') it is interpreted as a binary client ID, in which case the first byte is assumed to be the 'type' field as per RFC 2132 section 9.14 and the remaining bytes may be an hardware address (e.g. '01:xx:xx:xx:xx:xx:xx' where 1 is the Ethernet ARP type and the rest is a MAC address). If the property is not a hex string it is considered as a non-hardware-address client ID and the 'type' field is set to 0.
    dhcp-fqdn
    string
| If the "dhcp-send-hostname" property is TRUE, then the specified FQDN will be sent to the DHCP server when acquiring a lease. This property and "dhcp-hostname" are mutually exclusive and cannot be set at the same time.
    dhcp-hostname
    string
| If the "dhcp-send-hostname" property is TRUE, then the specified name will be sent to the DHCP server when acquiring a lease. This property and "dhcp-fqdn" are mutually exclusive and cannot be set at the same time.
    dhcp-send-hostname
    boolean
    TRUE
| If TRUE, a hostname is sent to the DHCP server when acquiring a lease. Some DHCP servers use this hostname to update DNS databases, essentially providing a static hostname for the computer. If the "dhcp-hostname" property is NULL and this property is TRUE, the current persistent hostname of the computer is sent.
    dhcp-timeout
    int32
    0
| A timeout for a DHCP transaction in seconds.
    dns
    array of uint32
    []
| Array of IP addresses of DNS servers (as network-byte-order integers)
    dns-options
    array of string
    []
| Array of DNS options as described in man 5 resolv.conf. NULL means that the options are unset and left at the default. In this case NetworkManager will use default options. This is distinct from an empty list of properties.
    dns-priority
    int32
    0
| Intra-connection DNS priority. The relative priority to be used when determining the order of DNS servers in resolv.conf. A lower value means that servers will be on top of the file. Zero selects the default value, which is 50 for VPNs and 100 for other connections. Note that the priority is to order DNS settings for multiple active connections. It does not disambiguate multiple DNS servers within the same connection profile. For that, just specify the DNS servers in the desired order. When multiple devices have configurations with the same priority, the one with an active default route will be preferred. Note that when using dns=dnsmasq the order is meaningless since dnsmasq forwards queries to all known servers at the same time. Negative values have the special effect of excluding other configurations with a greater priority value; so in presence of at least a negative priority, only DNS servers from connections with the lowest priority value will be used.
    dns-search
    array of string
    []
| Array of DNS search domains.
    gateway
    string
| The gateway associated with this configuration. This is only meaningful if "addresses" is also set.
    ignore-auto-dns
    boolean
    FALSE
| When "method" is set to "auto" and this property to TRUE, automatically configured nameservers and search domains are ignored and only nameservers and search domains specified in the "dns" and "dns-search" properties, if any, are used.
    ignore-auto-routes
    boolean
    FALSE
| When "method" is set to "auto" and this property to TRUE, automatically configured routes are ignored and only routes specified in the "routes" property, if any, are used.
    may-fail
    boolean
    TRUE
| If TRUE, allow overall network configuration to proceed even if the configuration specified by this property times out. Note that at least one IP configuration must succeed or overall network configuration will still fail. For example, in IPv6-only networks, setting this property to TRUE on the NMSettingIP4Config allows the overall network configuration to succeed if IPv4 configuration fails but IPv6 configuration completes successfully.
    method
    string
| IP configuration method. NMSettingIP4Config and NMSettingIP6Config both support "auto", "manual", and "link-local". See the subclass-specific documentation for other values. In general, for the "auto" method, properties such as "dns" and "routes" specify information that is added on to the information returned from automatic configuration. The "ignore-auto-routes" and "ignore-auto-dns" properties modify this behavior. For methods that imply no upstream network, such as "shared" or "link-local", these properties must be empty. For IPv4 method "shared", the IP subnet can be configured by adding one manual IPv4 address or otherwise 10.42.x.0/24 is chosen.
    name
    string
    ipv4
| The setting's name, which uniquely identifies the setting within the connection. Each setting type has a name unique to that type, for example "ppp" or "wireless" or "wired".
    never-default
    boolean
    FALSE
| If TRUE, this connection will never be the default connection for this IP type, meaning it will never be assigned the default route by NetworkManager.
    route-data
    array of vardict
| Array of IPv4 routes. Each route dictionary contains at least 'dest' and 'prefix' entries, containing the destination IP address as a string, and the prefix length as a uint32. Most routes will also have a 'gateway' entry, containing the gateway IP address as a string. If the route has a 'metric' entry (containing a uint32), that will be used as the metric for the route (otherwise NM will pick a default value appropriate to the device). Additional attributes may also exist on some routes.
    route-metric
    int64
    -1
| The default metric for routes that don't explicitly specify a metric. The default value -1 means that the metric is chosen automatically based on the device type. The metric applies to dynamic routes, manual (static) routes that don't have an explicit metric setting, address prefix routes, and the default route. Note that for IPv6, the kernel accepts zero (0) but coerces it to 1024 (user default). Hence, setting this property to zero effectively mean setting it to 1024. For IPv4, zero is a regular value for the metric.
    route-table
    uint32
    0
| Enable policy routing (source routing) and set the routing table used when adding routes. This affects all routes, including device-routes, IPv4LL, DHCP, SLAAC, default-routes and static routes. But note that static routes can individually overwrite the setting by explicitly specifying a non-zero routing table. If the table setting is left at zero, it is eligible to be overwritten via global configuration. If the property is zero even after applying the global configuration value, policy routing is disabled for the address family of this connection. Policy routing disabled means that NetworkManager will add all routes to the main table (except static routes that explicitly configure a different table). Additionally, NetworkManager will not delete any extraneous routes from tables except the main table. This is to preserve backward compatibility for users who manage routing tables outside of NetworkManager.
    routes
    array of array of uint32
    []
| Deprecated in favor of the 'route-data' property, but this can be used for backward-compatibility with older daemons. Note that if you send this property the daemon will ignore 'route-data'. Array of IPv4 route structures. Each IPv4 route structure is composed of 4 32-bit values; the first being the destination IPv4 network or address (network byte order), the second the destination network or address prefix (1 - 32), the third being the next-hop (network byte order) if any, and the fourth being the route metric. If the metric is 0, NM will choose an appropriate default metric for the device. (There is no way to explicitly specify an actual metric of 0 with this property.)