Type: nic
Description: Network devices, also referred to as Network Interface Controllers or NICs, supply a connection to a network. LXD supports several different types of network devices ( NIC types). nictype vs. netwo...

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# Type: `nic`

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Note

The `nic` device type is supported for both containers and VMs.

NICs support hotplugging for both containers and VMs (with the exception of the `ipvlan` NIC type).

Network devices, also referred to as Network Interface Controllers or NICs, supply a connection to a network. LXD supports several different types of network devices (NIC types).

## `nictype` vs. `network`

When adding a network device to an instance, there are two methods to specify the type of device that you want to add: through the `nictype` device option or the `network` device option.

These two device options are mutually exclusive, and you can specify only one of them when you create a device. However, note that when you specify the `network` option, the `nictype` option is derived automatically from the network type.

`nictype`

  When using the `nictype` device option, you can specify a network interface that is not controlled by LXD. Therefore, you must specify all information that LXD needs to use the network interface.

  When using this method, the `nictype` option must be specified when creating the device, and it cannot be changed later.

`network`

  When using the `network` device option, the NIC is linked to an existing managed network. In this case, LXD has all required information about the network, and you need to specify only the network name when adding the device.

  When using this method, LXD derives the `nictype` option automatically. The value is read-only and cannot be changed.

  Other device options that are inherited from the network are marked with a “yes” in the “Managed” field of the NIC-specific device options. You cannot customize these options directly for the NIC if you’re using the `network` method.

See Networking setups for more information.

## Available NIC types

The following NICs can be added using the `nictype` or `network` options:

- `bridged`: Uses an existing bridge on the host and creates a virtual device pair to connect the host bridge to the instance.

- `macvlan`: Sets up a new network device based on an existing one, but using a different MAC address.

- `sriov`: Passes a virtual function of an SR-IOV-enabled physical network device into the instance.

- `physical`: Passes a physical device from the host through to the instance. The targeted device will vanish from the host and appear in the instance.

The following NICs can be added using only the `network` option:

- `ovn`: Uses an existing OVN network and creates a virtual device pair to connect the instance to it.

The following NICs can be added using only the `nictype` option:

- `ipvlan`: Sets up a new network device based on an existing one, using the same MAC address but a different IP.

- `p2p`: Creates a virtual device pair, putting one side in the instance and leaving the other side on the host.

- `routed`: Creates a virtual device pair to connect the host to the instance and sets up static routes and proxy ARP/NDP entries to allow the instance to join the network of a designated parent interface.

The available device options depend on the NIC type and are listed in the following sections.

### `nictype`: `bridged`

Note

You can select this NIC type through the `nictype` option or the `network` option (see Bridge network for information about the managed `bridge` network).

A `bridged` NIC uses an existing bridge on the host and creates a virtual device pair to connect the host bridge to the instance.

#### Device options

NIC devices of type `bridged` have the following device options:

`boot.priority`

Boot priority for VMs

Key: | `boot.priority`
Type: | integer
Managed: | no

A higher value for this option means that the VM boots first.

`host_name`

Name of the interface inside the host

Key: | `host_name`
Type: | string
Default: | randomly assigned
Managed: | no

`hwaddr`

MAC address of the new interface

Key: | `hwaddr`
Type: | string
Default: | randomly assigned
Managed: | no

`ipv4.address`

IPv4 address to assign to the instance through DHCP

Key: | `ipv4.address`
Type: | string
Managed: | no

Set this option to `none` to restrict all IPv4 traffic when `security.ipv4_filtering` is set.

`ipv4.routes`

IPv4 static routes for the NIC to add on the host

Key: | `ipv4.routes`
Type: | string
Managed: | no

Specify a comma-delimited list of IPv4 static routes for this NIC to add on the host.

`ipv4.routes.external`

IPv4 static routes to route to NIC

Key: | `ipv4.routes.external`
Type: | string
Managed: | no

Specify a comma-delimited list of IPv4 static routes to route to the NIC and publish on the uplink network (BGP).

`ipv6.address`

IPv6 address to assign to the instance through DHCP

Key: | `ipv6.address`
Type: | string
Managed: | no

Set this option to `none` to restrict all IPv6 traffic when `security.ipv6_filtering` is set.

`ipv6.routes`

IPv6 static routes for the NIC to add on the host

Key: | `ipv6.routes`
Type: | string
Managed: | no

Specify a comma-delimited list of IPv6 static routes for this NIC to add on the host.

`ipv6.routes.external`

IPv6 static routes to route to NIC

Key: | `ipv6.routes.external`
Type: | string
Managed: | no

Specify a comma-delimited list of IPv6 static routes to route to the NIC and publish on the uplink network (BGP).

`limits.egress`

I/O limit for outgoing traffic

Key: | `limits.egress`
Type: | string
Managed: | no

Specify the limit in bit/s. Various suffixes are supported (see Units for storage and network limits).

`limits.ingress`

I/O limit for incoming traffic

Key: | `limits.ingress`
Type: | string
Managed: | no

Specify the limit in bit/s. Various suffixes are supported (see Units for storage and network limits).

`limits.max`

I/O limit for both incoming and outgoing traffic

Key: | `limits.max`
Type: | string
Managed: | no

This option is the same as setting both `limits.ingress` and `limits.egress`.

Specify the limit in bit/s. Various suffixes are supported (see Units for storage and network limits).

`limits.priority`

`skb->priority` value for outgoing traffic

Key: | `limits.priority`
Type: | integer
Managed: | no

The `skb->priority` value for outgoing traffic is used by the kernel queuing discipline (qdisc) to prioritize network packets. Specify the value as a 32-bit unsigned integer.

The effect of this value depends on the particular qdisc implementation, for example, `SKBPRIO` or `QFQ`. Consult the kernel qdisc documentation before setting this value.

`maas.subnet.ipv4`

MAAS IPv4 subnet to register the instance in

Key: | `maas.subnet.ipv4`
Type: | string
Managed: | yes

`maas.subnet.ipv6`

MAAS IPv6 subnet to register the instance in

Key: | `maas.subnet.ipv6`
Type: | string
Managed: | yes

`mtu`

MTU of the new interface

Key: | `mtu`
Type: | integer
Default: | parent MTU
Managed: | yes

`name`

Name of the interface inside the instance

Key: | `name`
Type: | string
Default: | kernel assigned
Managed: | no

`network`

Managed network to link the device to

Key: | `network`
Type: | string
Managed: | no

You can specify this option instead of specifying the `nictype` directly.

`parent`

Name of the host device

Key: | `parent`
Type: | string
Managed: | yes
Required: | if specifying the `nictype` directly

`queue.tx.length`

Transmit queue length for the NIC

Key: | `queue.tx.length`
Type: | integer
Managed: | no

`security.ipv4_filtering`

Whether to prevent the instance from spoofing an IPv4 address

Key: | `security.ipv4_filtering`
Type: | bool
Default: | `false`
Managed: | no

Set this option to `true` to prevent the instance from spoofing another instance’s IPv4 address. This option enables `security.mac_filtering`.

`security.ipv6_filtering`

Whether to prevent the instance from spoofing an IPv6 address

Key: | `security.ipv6_filtering`
Type: | bool
Default: | `false`
Managed: | no

Set this option to `true` to prevent the instance from spoofing another instance’s IPv6 address. This option enables `security.mac_filtering`.

`security.mac_filtering`

Whether to prevent the instance from spoofing a MAC address

Key: | `security.mac_filtering`
Type: | bool
Default: | `false`
Managed: | no

Set this option to `true` to prevent the instance from spoofing another instance’s MAC address.

`security.port_isolation`

Whether to respect port isolation

Key: | `security.port_isolation`
Type: | bool
Default: | `false`
Managed: | no

Set this option to `true` to prevent the NIC from communicating with other NICs in the network that have port isolation enabled.

`vlan`

VLAN ID to use for non-tagged traffic

Key: | `vlan`
Type: | integer
Managed: | no

Set this option to `none` to remove the port from the default VLAN.

`vlan.tagged`

VLAN IDs or VLAN ranges to join for tagged traffic

Key: | `vlan.tagged`
Type: | integer
Managed: | no

Specify the VLAN IDs or ranges as a comma-delimited list.

#### Configuration examples

Add a `bridged` network device to an instance, connecting to a LXD managed network:

    lxc network create <network_name> --type=bridge
    lxc config device add <instance_name> <device_name> nic network=<network_name>

Note that `bridge` is the type when creating a managed bridge network, while the device `nictype` that is required when connecting to an unmanaged bridge is `bridged`.

Add a `bridged` network device to an instance, connecting to an existing bridge interface with `nictype`:

    lxc config device add <instance_name> <device_name> nic nictype=bridged parent=<existing_bridge>

See How to create a network and Configure devices for more information.

### `nictype`: `macvlan`

Note

You can select this NIC type through the `nictype` option or the `network` option (see Macvlan network for information about the managed `macvlan` network).

A `macvlan` NIC sets up a new network device based on an existing one, but using a different MAC address.

If you are using a `macvlan` NIC, communication between the LXD host and the instances is not possible. Both the host and the instances can talk to the gateway, but they cannot communicate directly.

#### Device options

NIC devices of type `macvlan` have the following device options:

`boot.priority`

Boot priority for VMs

Key: | `boot.priority`
Type: | integer
Managed: | no

A higher value for this option means that the VM boots first.

`gvrp`

Whether to use GARP VLAN Registration Protocol

Key: | `gvrp`
Type: | bool
Default: | `false`
Managed: | no

This option specifies whether to register the VLAN using the GARP VLAN Registration Protocol.

`hwaddr`

MAC address of the new interface

Key: | `hwaddr`
Type: | string
Default: | randomly assigned
Managed: | no

`maas.subnet.ipv4`

MAAS IPv4 subnet to register the instance in

Key: | `maas.subnet.ipv4`
Type: | string
Managed: | yes

`maas.subnet.ipv6`

MAAS IPv6 subnet to register the instance in

Key: | `maas.subnet.ipv6`
Type: | string
Managed: | yes

`mtu`

MTU of the new interface

Key: | `mtu`
Type: | integer
Default: | parent MTU
Managed: | yes

`name`

Name of the interface inside the instance

Key: | `name`
Type: | string
Default: | kernel assigned
Managed: | no

`network`

Managed network to link the device to

Key: | `network`
Type: | string
Managed: | no

You can specify this option instead of specifying the `nictype` directly.

`parent`

Name of the host device

Key: | `parent`
Type: | string
Managed: | yes
Required: | if specifying the `nictype` directly

`vlan`

VLAN ID to attach to

Key: | `vlan`
Type: | integer
Managed: | no

#### Configuration examples

Add a `macvlan` network device to an instance, connecting to a LXD managed network:

    lxc network create <network_name> --type=macvlan parent=<existing_NIC>
    lxc config device add <instance_name> <device_name> nic network=<network_name>

Add a `macvlan` network device to an instance, connecting to an existing network interface with `nictype`:

    lxc config device add <instance_name> <device_name> nic nictype=macvlan parent=<existing_NIC>

See How to create a network and Configure devices for more information.

### `nictype`: `sriov`

Note

You can select this NIC type through the `nictype` option or the `network` option (see SR-IOV network for information about the managed `sriov` network).

An `sriov` NIC passes a virtual function of an SR-IOV-enabled physical network device into the instance.

An SR-IOV-enabled network device associates a set of virtual functions (VFs) with the single physical function (PF) of the network device. PFs are standard PCIe functions. VFs, on the other hand, are very lightweight PCIe functions that are optimized for data movement. They come with a limited set of configuration capabilities to prevent changing properties of the PF.

Given that VFs appear as regular PCIe devices to the system, they can be passed to instances just like a regular physical device.

VF allocation

  The `sriov` interface type expects to be passed the name of an SR-IOV enabled network device on the system via the `parent` property. LXD then checks for any available VFs on the system.

  By default, LXD allocates the first free VF it finds. If it detects that either none are enabled or all currently enabled VFs are in use, it bumps the number of supported VFs to the maximum value and uses the first free VF. If all possible VFs are in use or the kernel or card doesn’t support incrementing the number of VFs, LXD returns an error.

  Note

  If you need LXD to use a specific VF, use a `physical` NIC instead of a `sriov` NIC and set its `parent` option to the VF name.

#### Device options

NIC devices of type `sriov` have the following device options:

`boot.priority`

Boot priority for VMs

Key: | `boot.priority`
Type: | integer
Managed: | no

A higher value for this option means that the VM boots first.

`hwaddr`

MAC address of the new interface

Key: | `hwaddr`
Type: | string
Default: | randomly assigned
Managed: | no

`maas.subnet.ipv4`

MAAS IPv4 subnet to register the instance in

Key: | `maas.subnet.ipv4`
Type: | string
Managed: | yes

`maas.subnet.ipv6`

MAAS IPv6 subnet to register the instance in

Key: | `maas.subnet.ipv6`
Type: | string
Managed: | yes

`mtu`

MTU of the new interface

Key: | `mtu`
Type: | integer
Default: | kernel assigned
Managed: | yes

`name`

Name of the interface inside the instance

Key: | `name`
Type: | string
Default: | kernel assigned
Managed: | no

`network`

Managed network to link the device to

Key: | `network`
Type: | string
Managed: | no

You can specify this option instead of specifying the `nictype` directly.

`parent`

Name of the host device

Key: | `parent`
Type: | string
Managed: | yes
Required: | if specifying the `nictype` directly

`security.mac_filtering`

Whether to prevent the instance from spoofing a MAC address

Key: | `security.mac_filtering`
Type: | bool
Default: | `false`
Managed: | no

Set this option to `true` to prevent the instance from spoofing another instance’s MAC address.

`vlan`

VLAN ID to attach to

Key: | `vlan`
Type: | integer
Managed: | no

#### Configuration examples

Add a `sriov` network device to an instance, connecting to a LXD managed network:

    lxc network create <network_name> --type=sriov parent=<sriov_enabled_NIC>
    lxc config device add <instance_name> <device_name> nic network=<network_name>

Add a `sriov` network device to an instance, connecting to an existing SR-IOV-enabled interface with `nictype`:

    lxc config device add <instance_name> <device_name> nic nictype=sriov parent=<sriov_enabled_NIC>

See How to create a network and Configure devices for more information.

### `nictype`: `physical`

Note

- You can select this NIC type through the `nictype` option or the `network` option (see Physical network for information about the managed `physical` network).

- You can have only one `physical` NIC for each parent device.

A `physical` NIC provides straight physical device pass-through from the host. The targeted device will vanish from the host and appear in the instance (which means that you can have only one `physical` NIC for each targeted device).

#### Device options

NIC devices of type `physical` have the following device options:

`boot.priority`

Boot priority for VMs

Key: | `boot.priority`
Type: | integer
Managed: | no

A higher value for this option means that the VM boots first.

`gvrp`

Whether to use GARP VLAN Registration Protocol

Key: | `gvrp`
Type: | bool
Default: | `false`
Managed: | no

This option specifies whether to register the VLAN using the GARP VLAN Registration Protocol.

`hwaddr`

MAC address of the new interface

Key: | `hwaddr`
Type: | string
Default: | parent MAC address
Condition: | container
Managed: | no

`maas.subnet.ipv4`

MAAS IPv4 subnet to register the instance in

Key: | `maas.subnet.ipv4`
Type: | string
Managed: | no

`maas.subnet.ipv6`

MAAS IPv6 subnet to register the instance in

Key: | `maas.subnet.ipv6`
Type: | string
Managed: | no

`mtu`

MTU of the new interface

Key: | `mtu`
Type: | integer
Default: | parent MTU
Condition: | container
Managed: | no

`name`

Name of the interface inside the instance

Key: | `name`
Type: | string
Default: | kernel assigned
Managed: | no

`network`

Managed network to link the device to

Key: | `network`
Type: | string
Managed: | no

You can specify this option instead of specifying the `nictype` directly.

`parent`

Name of the host device

Key: | `parent`
Type: | string
Managed: | yes
Required: | if specifying the `nictype` directly

`vlan`

VLAN ID to attach to

Key: | `vlan`
Type: | integer
Condition: | container
Managed: | no

#### Configuration examples

Add a `physical` network device to an instance, connecting to an existing physical network interface with `nictype`:

    lxc config device add <instance_name> <device_name> nic nictype=physical parent=<physical_NIC>

Adding a `physical` network device to an instance using a managed network is not possible, because the `physical` managed network type is intended to be used only with OVN networks.

See Configure devices for more information.

### `nictype`: `ovn`

Note

You can select this NIC type only through the `network` option (see OVN network for information about the managed `ovn` network).

An `ovn` NIC uses an existing OVN network and creates a virtual device pair to connect the instance to it.

SR-IOV hardware acceleration

  To use `acceleration=sriov`, you must have a compatible SR-IOV physical NIC that supports the Ethernet switch device driver model (`switchdev`) in your LXD host. LXD assumes that the physical NIC (PF) is configured in `switchdev` mode and connected to the OVN integration OVS bridge, and that it has one or more virtual functions (VFs) active.

  To achieve this, follow these basic prerequisite setup steps:

  1. Set up PF and VF:

     1. Activate some VFs on PF (called `enp9s0f0np0` in the following example, with a PCI address of `0000:09:00.0`) and unbind them.

     2. Enable `switchdev` mode and `hw-tc-offload` on the PF.

     3. Rebind the VFs.

         echo 4 > /sys/bus/pci/devices/0000:09:00.0/sriov_numvfs
         for i in $(lspci -nnn | grep "Virtual Function" | cut -d' ' -f1); do echo 0000:$i > /sys/bus/pci/drivers/mlx5_core/unbind; done
         devlink dev eswitch set pci/0000:09:00.0 mode switchdev
         ethtool -K enp9s0f0np0 hw-tc-offload on
         for i in $(lspci -nnn | grep "Virtual Function" | cut -d' ' -f1); do echo 0000:$i > /sys/bus/pci/drivers/mlx5_core/bind; done

  2. Set up OVS by enabling hardware offload and adding the PF NIC to the integration bridge (normally called `br-int`):

         ovs-vsctl set open_vswitch . other_config:hw-offload=true
         systemctl restart openvswitch-switch
         ovs-vsctl add-port br-int enp9s0f0np0
         ip link set enp9s0f0np0 up

VDPA hardware acceleration

  To use `acceleration=vdpa`, you must have a compatible VDPA physical NIC. The setup is the same as for SR-IOV hardware acceleration, except that you must also enable the `vhost_vdpa` module and check that you have some available VDPA management devices :

      modprobe vhost_vdpa && vdpa mgmtdev show

#### Device options

NIC devices of type `ovn` have the following device options:

`acceleration`

Enable hardware offloading

Key: | `acceleration`
Type: | string
Default: | `none`
Managed: | no

Possible values are `none`, `sriov`, or `vdpa`. See SR-IOV hardware acceleration for more information.

`boot.priority`

Boot priority for VMs

Key: | `boot.priority`
Type: | integer
Managed: | no

A higher value for this option means that the VM boots first.

`host_name`

Name of the interface inside the host

Key: | `host_name`
Type: | string
Default: | randomly assigned
Managed: | no

`hwaddr`

MAC address of the new interface

Key: | `hwaddr`
Type: | string
Default: | randomly assigned
Managed: | no

`ipv4.address`

IPv4 address to assign to the instance through DHCP

Key: | `ipv4.address`
Type: | string
Managed: | no

`ipv4.routes`

IPv4 static routes to route for the NIC

Key: | `ipv4.routes`
Type: | string
Managed: | no

Specify a comma-delimited list of IPv4 static routes to route for this NIC.

`ipv4.routes.external`

IPv4 static routes to route to NIC

Key: | `ipv4.routes.external`
Type: | string
Managed: | no

Specify a comma-delimited list of IPv4 static routes to route to the NIC and publish on the uplink network.

`ipv6.address`

IPv6 address to assign to the instance through DHCP

Key: | `ipv6.address`
Type: | string
Managed: | no

`ipv6.routes`

IPv6 static routes to route to the NIC

Key: | `ipv6.routes`
Type: | string
Managed: | no

Specify a comma-delimited list of IPv6 static routes to route to the NIC.

`ipv6.routes.external`

IPv6 static routes to route to NIC

Key: | `ipv6.routes.external`
Type: | string
Managed: | no

Specify a comma-delimited list of IPv6 static routes to route to the NIC and publish on the uplink network.

`name`

Name of the interface inside the instance

Key: | `name`
Type: | string
Default: | kernel assigned
Managed: | no

`nested`

Parent NIC name to nest this NIC under

Key: | `nested`
Type: | string
Managed: | no

See also `vlan`.

`network`

Managed network to link the device to

Key: | `network`
Type: | string
Managed: | yes
Required: | yes

`security.acls`

Network ACLs to apply

Key: | `security.acls`
Type: | string
Managed: | no

Specify a comma-separated list

`security.acls.default.egress.action`

Default action to use for egress traffic

Key: | `security.acls.default.egress.action`
Type: | string
Default: | `reject`
Managed: | no

The specified action is used for all egress traffic that doesn’t match any ACL rule.

`security.acls.default.egress.logged`

Whether to log egress traffic that doesn’t match any ACL rule

Key: | `security.acls.default.egress.logged`
Type: | bool
Default: | `false`
Managed: | no

`security.acls.default.ingress.action`

Default action to use for ingress traffic

Key: | `security.acls.default.ingress.action`
Type: | string
Default: | `reject`
Managed: | no

The specified action is used for all ingress traffic that doesn’t match any ACL rule.

`security.acls.default.ingress.logged`

Whether to log ingress traffic that doesn’t match any ACL rule

Key: | `security.acls.default.ingress.logged`
Type: | bool
Default: | `false`
Managed: | no

`vlan`

VLAN ID to use when nesting

Key: | `vlan`
Type: | integer
Managed: | no

See also `nested`.

#### Configuration examples

An `ovn` network device must be added using a managed network. To do so:

    lxc network create <network_name> --type=ovn network=<parent_network>
    lxc config device add <instance_name> <device_name> nic network=<network_name>

See How to set up OVN with LXD for full instructions, and How to create a network and Configure devices for more information.

### `nictype`: `ipvlan`

Note

- This NIC type is available only for containers, not for virtual machines.

- You can select this NIC type only through the `nictype` option.

- This NIC type does not support hotplugging.

An `ipvlan` NIC sets up a new network device based on an existing one, using the same MAC address but a different IP.

If you are using an `ipvlan` NIC, communication between the LXD host and the instances is not possible. Both the host and the instances can talk to the gateway, but they cannot communicate directly.

LXD currently supports IPVLAN in L2 and L3S mode. In this mode, the gateway is automatically set by LXD, but the IP addresses must be manually specified using the `ipv4.address` and/or `ipv6.address` options before the container is started.

DNS

  The name servers must be configured inside the container, because they are not set automatically. To do this, set the following `sysctls`:

  - When using IPv4 addresses:

        net.ipv4.conf.<parent>.forwarding=1

  - When using IPv6 addresses:

        net.ipv6.conf.<parent>.forwarding=1
        net.ipv6.conf.<parent>.proxy_ndp=1

#### Device options

NIC devices of type `ipvlan` have the following device options:

`gvrp`

Whether to use GARP VLAN Registration Protocol

Key: | `gvrp`
Type: | bool
Default: | `false`

This option specifies whether to register the VLAN using the GARP VLAN Registration Protocol.

`hwaddr`

MAC address of the new interface

Key: | `hwaddr`
Type: | string
Default: | randomly assigned

`ipv4.address`

IPv4 static addresses to add to the instance

Key: | `ipv4.address`
Type: | string

Specify a comma-delimited list of IPv4 static addresses to add to the instance. In `l2` mode, you can specify them as CIDR values or singular addresses using a subnet of `/24`.

`ipv4.gateway`

IPv4 gateway

Key: | `ipv4.gateway`
Type: | string
Default: | `auto` (`l3s`), `-` (`l2`)

In `l3s` mode, the option specifies whether to add an automatic default IPv4 gateway. Possible values are `auto` and `none`.

In `l2` mode, this option specifies the IPv4 address of the gateway.

`ipv4.host_table`

Custom policy routing table ID to add IPv4 static routes to

Key: | `ipv4.host_table`
Type: | integer

The custom policy routing table is in addition to the main routing table.

`ipv6.address`

IPv6 static addresses to add to the instance

Key: | `ipv6.address`
Type: | string

Specify a comma-delimited list of IPv6 static addresses to add to the instance. In `l2` mode, you can specify them as CIDR values or singular addresses using a subnet of `/64`.

`ipv6.gateway`

IPv6 gateway

Key: | `ipv6.gateway`
Type: | string
Default: | `auto` (`l3s`), `-` (`l2`)

In `l3s` mode, the option specifies whether to add an automatic default IPv6 gateway. Possible values are `auto` and `none`.

In `l2` mode, this option specifies the IPv6 address of the gateway.

`ipv6.host_table`

Custom policy routing table ID to add IPv6 static routes to

Key: | `ipv6.host_table`
Type: | integer

The custom policy routing table is in addition to the main routing table.

`mode`

IPVLAN mode

Key: | `mode`
Type: | string
Default: | `l3s`

Possible values are `l2` and `l3s`.

`mtu`

The MTU of the new interface

Key: | `mtu`
Type: | integer
Default: | parent MTU

`name`

Name of the interface inside the instance

Key: | `name`
Type: | string
Default: | kernel assigned

`parent`

Name of the host device

Key: | `parent`
Type: | string
Required: | yes

`vlan`

VLAN ID to attach to

Key: | `vlan`
Type: | integer

#### Configuration examples

Add an `ipvlan` network device to an instance, connecting to an existing network interface with `nictype`:

    lxc stop <instance_name>
    lxc config device add <instance_name> <device_name> nic nictype=ipvlan parent=<existing_NIC>

Adding an `ipvlan` network device to an instance using a managed network is not possible.

See Configure devices for more information.

### `nictype`: `p2p`

Note

You can select this NIC type only through the `nictype` option.

A `p2p` NIC creates a virtual device pair, putting one side in the instance and leaving the other side on the host.

#### Device options

NIC devices of type `p2p` have the following device options:

`boot.priority`

Boot priority for VMs

Key: | `boot.priority`
Type: | integer

A higher value for this option means that the VM boots first.

`host_name`

Name of the interface inside the host

Key: | `host_name`
Type: | string
Default: | randomly assigned

`hwaddr`

MAC address of the new interface

Key: | `hwaddr`
Type: | string
Default: | randomly assigned

`ipv4.routes`

IPv4 static routes for the NIC to add on the host

Key: | `ipv4.routes`
Type: | string

Specify a comma-delimited list of IPv4 static routes for this NIC to add on the host.

`ipv6.routes`

IPv6 static routes for the NIC to add on the host

Key: | `ipv6.routes`
Type: | string

Specify a comma-delimited list of IPv6 static routes for this NIC to add on the host.

`limits.egress`

I/O limit for outgoing traffic

Key: | `limits.egress`
Type: | string

Specify the limit in bit/s. Various suffixes are supported (see Units for storage and network limits).

`limits.ingress`

I/O limit for incoming traffic

Key: | `limits.ingress`
Type: | string

Specify the limit in bit/s. Various suffixes are supported (see Units for storage and network limits).

`limits.max`

I/O limit for both incoming and outgoing traffic

Key: | `limits.max`
Type: | string

This option is the same as setting both `limits.ingress` and `limits.egress`.

Specify the limit in bit/s. Various suffixes are supported (see Units for storage and network limits).

`limits.priority`

`skb->priority` value for outgoing traffic

Key: | `limits.priority`
Type: | integer

The `skb->priority` value for outgoing traffic is used by the kernel queuing discipline (qdisc) to prioritize network packets. Specify the value as a 32-bit unsigned integer.

The effect of this value depends on the particular qdisc implementation, for example, `SKBPRIO` or `QFQ`. Consult the kernel qdisc documentation before setting this value.

`mtu`

MTU of the new interface

Key: | `mtu`
Type: | integer
Default: | kernel assigned

`name`

Name of the interface inside the instance

Key: | `name`
Type: | string
Default: | kernel assigned

`queue.tx.length`

Transmit queue length for the NIC

Key: | `queue.tx.length`
Type: | integer

#### Configuration examples

Add a `p2p` network device to an instance using `nictype`:

    lxc config device add <instance_name> <device_name> nic nictype=p2p

Adding a `p2p` network device to an instance using a managed network is not possible.

See Configure devices for more information.

### `nictype`: `routed`

Note

You can select this NIC type only through the `nictype` option.

A `routed` NIC creates a virtual device pair to connect the host to the instance and sets up static routes and proxy ARP/NDP entries to allow the instance to join the network of a designated parent interface. For containers it uses a virtual Ethernet device pair, and for VMs it uses a TAP device.

This NIC type is similar in operation to `ipvlan`, in that it allows an instance to join an external network without needing to configure a bridge and shares the host’s MAC address. However, it differs from `ipvlan` because it does not need IPVLAN support in the kernel, and the host and the instance can communicate with each other.

This NIC type respects `netfilter` rules on the host and uses the host’s routing table to route packets, which can be useful if the host is connected to multiple networks.

IP addresses, gateways and routes

  You must manually specify the IP addresses (using `ipv4.address` and/or `ipv6.address`) before the instance is started.

  For containers, the NIC configures the following link-local gateway IPs on the host end and sets them as the default gateways in the container’s NIC interface:

      169.254.0.1
      fe80::1

  For VMs, the gateways must be configured manually or via a mechanism like `cloud-init` (see the how to guide).

  Note

  If your container image is configured to perform DHCP on the interface, it will likely remove the automatically added configuration. In this case, you must configure the IP addresses and gateways manually or via a mechanism like `cloud-init`.

  The NIC type configures static routes on the host pointing to the instance’s `veth` interface for all of the instance’s IPs.

Multiple IP addresses

  Each NIC device can have multiple IP addresses added to it.

  However, it might be preferable to use multiple `routed` NIC interfaces instead. In this case, set the `ipv4.gateway` and `ipv6.gateway` values to `none` on any subsequent interfaces to avoid default gateway conflicts. Also consider specifying a different host-side address for these subsequent interfaces using `ipv4.host_address` and/or `ipv6.host_address`.

Parent interface

  This NIC can operate with and without a `parent` network interface set.

  With the `parent` network interface set, proxy ARP/NDP entries of the instance’s IPs are added to the parent interface, which allows the instance to join the parent interface’s network at layer 2.

  To enable this, the following network configuration must be applied on the host via `sysctl`:

  - When using IPv4 addresses:

        net.ipv4.conf.<parent>.forwarding=1

  - When using IPv6 addresses:

        net.ipv6.conf.all.forwarding=1
        net.ipv6.conf.<parent>.forwarding=1
        net.ipv6.conf.all.proxy_ndp=1
        net.ipv6.conf.<parent>.proxy_ndp=1

#### Device options

NIC devices of type `routed` have the following device options:

`gvrp`

Whether to use GARP VLAN Registration Protocol

Key: | `gvrp`
Type: | bool
Default: | `false`

This option specifies whether to register the VLAN using the GARP VLAN Registration Protocol.

`host_name`

Name of the interface inside the host

Key: | `host_name`
Type: | string
Default: | randomly assigned

`hwaddr`

MAC address of the new interface

Key: | `hwaddr`
Type: | string
Default: | randomly assigned

`ipv4.address`

IPv4 static addresses to add to the instance

Key: | `ipv4.address`
Type: | string

Specify a comma-delimited list of IPv4 static addresses to add to the instance.

`ipv4.gateway`

Whether to add an automatic default IPv4 gateway

Key: | `ipv4.gateway`
Type: | string
Default: | `auto`

Possible values are `auto` and `none`.

`ipv4.host_address`

IPv4 address to add to the host-side `veth` interface

Key: | `ipv4.host_address`
Type: | string
Default: | `169.254.0.1`

`ipv4.host_table`

Custom policy routing table ID to add IPv4 static routes to

Key: | `ipv4.host_table`
Type: | integer

The custom policy routing table is in addition to the main routing table.

`ipv4.neighbor_probe`

Whether to probe the parent network for IPv4 address availability

Key: | `ipv4.neighbor_probe`
Type: | bool
Default: | `true`

`ipv4.routes`

IPv4 static routes for the NIC to add on the host

Key: | `ipv4.routes`
Type: | string

Specify a comma-delimited list of IPv4 static routes for this NIC to add on the host (without L2 ARP/NDP proxy).

`ipv6.address`

IPv6 static addresses to add to the instance

Key: | `ipv6.address`
Type: | string

Specify a comma-delimited list of IPv6 static addresses to add to the instance.

`ipv6.gateway`

Whether to add an automatic default IPv6 gateway

Key: | `ipv6.gateway`
Type: | string
Default: | `auto`

Possible values are `auto` and `none`.

`ipv6.host_address`

IPv6 address to add to the host-side `veth` interface

Key: | `ipv6.host_address`
Type: | string
Default: | `fe80::1`

`ipv6.host_table`

Custom policy routing table ID to add IPv6 static routes to

Key: | `ipv6.host_table`
Type: | integer

The custom policy routing table is in addition to the main routing table.

`ipv6.neighbor_probe`

Whether to probe the parent network for IPv6 address availability

Key: | `ipv6.neighbor_probe`
Type: | bool
Default: | `true`

`ipv6.routes`

IPv6 static routes for the NIC to add on the host

Key: | `ipv6.routes`
Type: | string

Specify a comma-delimited list of IPv6 static routes for this NIC to add on the host (without L2 ARP/NDP proxy).

`limits.egress`

I/O limit for outgoing traffic

Key: | `limits.egress`
Type: | string

Specify the limit in bit/s. Various suffixes are supported (see Units for storage and network limits).

`limits.ingress`

I/O limit for incoming traffic

Key: | `limits.ingress`
Type: | string

Specify the limit in bit/s. Various suffixes are supported (see Units for storage and network limits).

`limits.max`

I/O limit for both incoming and outgoing traffic

Key: | `limits.max`
Type: | string

This option is the same as setting both `limits.ingress` and `limits.egress`.

Specify the limit in bit/s. Various suffixes are supported (see Units for storage and network limits).

`limits.priority`

`skb->priority` value for outgoing traffic

Key: | `limits.priority`
Type: | integer

The `skb->priority` value for outgoing traffic is used by the kernel queuing discipline (qdisc) to prioritize network packets. Specify the value as a 32-bit unsigned integer.

The effect of this value depends on the particular qdisc implementation, for example, `SKBPRIO` or `QFQ`. Consult the kernel qdisc documentation before setting this value.

`mtu`

The MTU of the new interface

Key: | `mtu`
Type: | integer
Default: | parent MTU

`name`

Name of the interface inside the instance

Key: | `name`
Type: | string
Default: | kernel assigned

`parent`

Name of the host device to join the instance to

Key: | `parent`
Type: | string

`queue.tx.length`

Transmit queue length for the NIC

Key: | `queue.tx.length`
Type: | integer

`vlan`

VLAN ID to attach to

Key: | `vlan`
Type: | integer

#### Configuration examples

Add a `routed` network device to an instance using `nictype`:

    lxc config device add <instance_name> <device_name> nic nictype=routed ipv4.address=192.0.2.2 ipv6.address=2001:db8::2

Adding a `routed` network device to an instance using a managed network is not possible.

See Configure devices for more information.

## `bridged`, `macvlan` or `ipvlan` for connection to physical network

The `bridged`, `macvlan` and `ipvlan` interface types can be used to connect to an existing physical network.

`macvlan` effectively lets you fork your physical NIC, getting a second interface that is then used by the instance. This method saves you from creating a bridge device and virtual Ethernet device pairs and usually offers better performance than a bridge.

The downside to this method is that `macvlan` devices, while able to communicate between themselves and to the outside, cannot talk to their parent device. This means that you can’t use `macvlan` if you ever need your instances to talk to the host itself.

In such case, a `bridge` device is preferable. A bridge also lets you use MAC filtering and I/O limits, which cannot be applied to a `macvlan` device.

`ipvlan` is similar to `macvlan`, with the difference being that the forked device has IPs statically assigned to it and inherits the parent’s MAC address on the network.

## MAAS integration

If you’re using MAAS to manage the physical network under your LXD host and want to attach your instances directly to a MAAS-managed network, LXD can be configured to interact with MAAS so that it can track your instances.

At the daemon level, you must configure `maas.api.url` and `maas.api.key`, and then set the NIC-specific `maas.subnet.ipv4` and/or `maas.subnet.ipv6` keys on the instance or profile’s `nic` entry.

With this configuration, LXD registers all your instances with MAAS, giving them proper DHCP leases and DNS records.

If you set the `ipv4.address` or `ipv6.address` keys on the NIC, those are registered as static assignments in MAAS.