Chapter 15. Configuring VLAN tagging

This section describes how to configure Virtual Local Area Network (VLAN). A VLAN is a logical network within a physical network. The VLAN interface tags packets with the VLAN ID as they pass through the interface, and removes tags of returning packets.

You create a VLAN interface on top of another interface, such as Ethernet, bond, team, or bridge. This interface is called the parent interface.

15.1. Configuring VLAN tagging using nm-connection-editor

This section describes how to configure Virtual Local Area Network (VLAN) tagging using the nm-connection-editor application.

Prerequisites

  • The interface you plan to use as a parent to the virtual VLAN interface supports VLAN tags.

  • If you configure the VLAN on top of a bond interface:

    • The slaves of the bond are up.
    • The bond is not configured with the fail_over_mac=follow option. A VLAN virtual device cannot change its MAC address to match the parent’s new MAC address. In such a case, the traffic would still be sent with the then incorrect source MAC address.
  • The switch the host is connected to is configured to support VLAN tags. For details, see the documentation of your switch.

Procedure

  1. Open a terminal, and enter nm-connection-editor: 

    $ nm-connection-editor
  2. Click the + button to add a new connection.
  3. Select the VLAN connection type, and click Create.

  4. On the VLAN tab:

    1. Select the parent interface.
    2. Select the VLAN id. Note that the VLAN must be within the range from 0 to 4094.
    3. By default, the VLAN connection inherits the maximum transmission unit (MTU) from the parent interface. Optionally, set a different MTU value.

    4. Optionally, set the name of the VLAN interface and further VLAN-specific options.

      vlan settings nm connection editor

  5. On the IPv4 Settings tab, configure the IPv4 settings. For example, set a static IPv4 address, network mask, default gateway, and DNS server: vlan IPv4 settings nm connection editor
  6. On the IPv6 Settings tab, configure the IPv6 settings. For example, set a static IPv6 address, network mask, default gateway, and DNS server: vlan IPv6 settings nm connection editor
  7. Click Save to save the VLAN connection.
  8. Close nm-connection-editor.

Verification steps

  1. Verify the settings: 

    # ip -d addr show vlan10
4: vlan10@enp1s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 52:54:00:d5:e0:fb brd ff:ff:ff:ff:ff:ff promiscuity 0
    vlan protocol 802.1Q id 10 <REORDER_HDR> numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535
    inet 192.0.2.1/24 brd 192.0.2.255 scope global noprefixroute vlan10
       valid_lft forever preferred_lft forever
    inet6 fe80::8dd7:9030:6f8e:89e6/64 scope link noprefixroute
       valid_lft forever preferred_lft forever

Additional resources

15.2. Configuring VLAN tagging using nmcli commands

This section describes how to configure Virtual Local Area Network (VLAN) tagging using nmcli commands.

Prerequisites

  • The interface you plan to use as a parent to the virtual VLAN interface supports VLAN tags.

  • If you configure the VLAN on top of a bond interface:

    • The slaves of the bond are up.
    • The bond is not configured with the fail_over_mac=follow option. A VLAN virtual device cannot change its MAC address to match the parent’s new MAC address. In such a case, the traffic would still be sent with the then incorrect source MAC address.
  • The switch the host is connected to is configured to support VLAN tags. For details, see the documentation of your switch.

Procedure

  1. Optionally, display the available network interfaces: 

    # ip address show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: enp1s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
    link/ether 52:54:00:d5:e0:fb brd ff:ff:ff:ff:ff:ff

  2. Create the VLAN interface. For example, to create a VLAN interface named vlan10 that uses enp1s0 as its parent interface and that tags packets with VLAN ID 10, enter: 

    # nmcli connection add type vlan con-name vlan10 ifname vlan10 vlan.parent enp1s0 vlan.id 10

    Note that the VLAN must be within the range from 0 to 4094.

  3. By default, the VLAN connection inherits the maximum transmission unit (MTU) from the parent interface. Optionally, set a different MTU value: 

    # nmcli connection modify vlan10 802-3-ethernet.mtu 2000

  4. Configure the IPv4 settings. For example, to set a static IPv4 address, network mask, default gateway, and DNS server to the vlan10 connection, enter: 

    # nmcli connection modify vlan10 ipv4.addresses '192.0.2.1/24'
# nmcli connection modify vlan10 ipv4.gateway '192.0.2.254'
# nmcli connection modify vlan10 ipv4.dns '192.0.2.253'
# nmcli connection modify vlan10 ipv4.method manual

  5. Configure the IPv6 settings. For example, to set a static IPv6 address, network mask, default gateway, and DNS server to the vlan10 connection, enter: 

    # nmcli connection modify vlan10 ipv6.addresses '2001:db8:1::1/32'
# nmcli connection modify vlan10 ipv6.gateway '2001:db8:1::fffe'
# nmcli connection modify vlan10 ipv6.dns '2001:db8:1::fffd'
# nmcli connection modify vlan10 ipv6.method manual

Verification steps

  1. Verify the settings. 

    # ip -d addr show vlan10
4: vlan10@enp1s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 52:54:00:d5:e0:fb brd ff:ff:ff:ff:ff:ff promiscuity 0
    vlan protocol 802.1Q id 10 <REORDER_HDR> numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535
    inet 192.0.2.1/24 brd 192.0.2.255 scope global noprefixroute vlan10
       valid_lft forever preferred_lft forever
    inet6 fe80::8dd7:9030:6f8e:89e6/64 scope link noprefixroute
       valid_lft forever preferred_lft forever

Additional resources

  • For more information on testing connections, see Chapter 33, Testing basic network settings.
  • For nmcli examples, see the nmcli-examples(7) man page.
  • For all vlan properties you can set, see the vlan setting section in the nm-settings(5) man page.