Chapter 9. Configuring VLAN tagging

Procedure

1. Display the network interfaces:

   # nmcli device status
   DEVICE   TYPE      STATE         CONNECTION
   enp1s0   ethernet  disconnected  enp1s0
   bridge0  bridge    connected     bridge0
   bond0    bond      connected     bond0
   ...

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 ethernet.mtu 2000

4. Configure the IP settings of the VLAN device. Skip this step if you want to use this VLAN device as a port of other devices.

   1. 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

   2. 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

5. Activate the connection:

   # nmcli connection up vlan10

Procedure

1. Select the Networking tab in the navigation on the left side of the screen.
2. Click Add VLAN in the Interfaces section.
3. Select the parent device.
4. Enter the VLAN ID.

5. Enter the name of the VLAN device or keep the automatically-generated name.

   
6. Click Apply.

7. By default, the VLAN device uses a dynamic IP address. If you want to set a static IP address:

   1. Click the name of the VLAN device in the Interfaces section.
   2. Click Edit next to the protocol you want to configure.
   3. Select Manual next to Addresses, and enter the IP address, prefix, and default gateway.
   4. In the DNS section, click the + button, and enter the IP address of the DNS server. Repeat this step to set multiple DNS servers.
   5. In the DNS search domains section, click the + button, and enter the search domain.

   6. If the interface requires static routes, configure them in the Routes section.

      
   7. Click Apply

Procedure

1. If you do not know the network device name on which you want configure VLAN tagging, display the available devices:

   # nmcli device status
   DEVICE     TYPE      STATE                   CONNECTION
   enp1s0     ethernet  unavailable             --
   ...

2. Start nmtui:

   # nmtui

3. Select Edit a connection, and press Enter.
4. Press the Add button.
5. Select VLAN from the list of network types, and press Enter.
6. Optional: Enter a name for the NetworkManager profile to be created.
7. Enter the VLAN device name to be created into the Device field.
8. Enter the name of the device on which you want to configure VLAN tagging into the Parent field.
9. Enter the VLAN ID. The ID must be within the range from 0 to 4094.

10. Depending on your environment, configure the IP address settings in the IPv4 configuration and IPv6 configuration areas accordingly. For this, press the Automatic button, and select:

    • Disabled, if this VLAN device does not require an IP address or you want to use it as a port of other devices.
    • Automatic, if a DHCP server dynamically assigns an IP address to the VLAN device.

    • Manual, if the network requires static IP address settings. In this case, you must fill further fields:

      1. Press the Show button next to the protocol you want to configure to display additional fields.

      2. Press the Add button next to Addresses, and enter the IP address and the subnet mask in Classless Inter-Domain Routing (CIDR) format.

         If you do not specify a subnet mask, NetworkManager sets a /32 subnet mask for IPv4 addresses and /64 for IPv6 addresses.

      3. Enter the address of the default gateway.
      4. Press the Add button next to DNS servers, and enter the DNS server address.
      5. Press the Add button next to Search domains, and enter the DNS search domain.

    Figure 9.1. Example of a VLAN connection with static IP address settings

    
11. Press the OK button to create and automatically activate the new connection.
12. Press the Back button to return to the main menu.
13. Select Quit, and press Enter to close the nmtui application.

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.

      

5. Configure the IP settings of the VLAN device. Skip this step if you want to use this VLAN device as a port of other devices.

   1. On the IPv4 Settings tab, configure the IPv4 settings. For example, set a static IPv4 address, network mask, default gateway, and DNS server:
   2. On the IPv6 Settings tab, configure the IPv6 settings. For example, set a static IPv6 address, network mask, default gateway, and DNS server:
6. Click Save to save the VLAN connection.
7. 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 2001:db8:1::1/32 scope global noprefixroute
          valid_lft forever preferred_lft forever
       inet6 fe80::8dd7:9030:6f8e:89e6/64 scope link noprefixroute
          valid_lft forever preferred_lft forever

Procedure

1. Create a YAML file, for example ~/create-vlan.yml, with the following contents:

   ---
   interfaces:
   - name: vlan10
     type: vlan
     state: up
     ipv4:
       enabled: true
       address:
       - ip: 192.0.2.1
         prefix-length: 24
       dhcp: false
     ipv6:
       enabled: true
       address:
       - ip: 2001:db8:1::1
         prefix-length: 64
       autoconf: false
       dhcp: false
     vlan:
       base-iface: enp1s0
       id: 10
   - name: enp1s0
     type: ethernet
     state: up
   
   routes:
     config:
     - destination: 0.0.0.0/0
       next-hop-address: 192.0.2.254
       next-hop-interface: vlan10
     - destination: ::/0
       next-hop-address: 2001:db8:1::fffe
       next-hop-interface: vlan10
   
   dns-resolver:
     config:
       search:
       - example.com
       server:
       - 192.0.2.200
       - 2001:db8:1::ffbb

2. Apply the settings to the system:

   # nmstatectl apply ~/create-vlan.yml

Verification steps

1. Display the status of the devices and connections:

   # nmcli device status
   DEVICE      TYPE      STATE      CONNECTION
   vlan10      vlan      connected  vlan10

2. Display all settings of the connection profile:

   # nmcli connection show vlan10
   connection.id:              vlan10
   connection.uuid:            1722970f-788e-4f81-bd7d-a86bf21c9df5
   connection.stable-id:       --
   connection.type:            vlan
   connection.interface-name:  vlan10
   ...

3. Display the connection settings in YAML format:

   # nmstatectl show vlan0

Procedure

1. If the host on which you want to execute the instructions in the playbook is not yet inventoried, add the IP or name of this host to the /etc/ansible/hosts Ansible inventory file:

   node.example.com

2. Create the ~/vlan-ethernet.yml playbook with the following content:

   ---
   - name: Configure a VLAN that uses an Ethernet connection
     hosts: node.example.com
     become: true
     tasks:
     - include_role:
         name: rhel-system-roles.network
   
       vars:
         network_connections:
           # Add an Ethernet profile for the underlying device of the VLAN
           - name: enp1s0
             type: ethernet
             interface_name: enp1s0
             autoconnect: yes
             state: up
             ip:
               dhcp4: no
               auto6: no
   
           # Define the VLAN profile
           - name: enp1s0.10
             type: vlan
             ip:
               address:
                 - "192.0.2.1/24"
                 - "2001:db8:1::1/64"
               gateway4: 192.0.2.254
               gateway6: 2001:db8:1::fffe
               dns:
                 - 192.0.2.200
                 - 2001:db8:1::ffbb
               dns_search:
                 - example.com
             vlan_id: 10
             parent: enp1s0
             state: up

   The parent attribute in the VLAN profile configures the VLAN to operate on top of the enp1s0 device.

3. Run the playbook:

   • To connect as root user to the managed host, enter:

     # ansible-playbook -u root ~/vlan-ethernet.yml

   • To connect as a user to the managed host, enter:

     # ansible-playbook -u user_name --ask-become-pass ~/vlan-ethernet.yml

     The --ask-become-pass option makes sure that the ansible-playbook command prompts for the sudo password of the user defined in the -u user_name option.

   If you do not specify the -u user_name option, ansible-playbook connects to the managed host as the user that is currently logged in to the control node.