Installation and Features

Installing bridge-utils:
sudo apt install bridge-utils

Notes:

• Wi-Fi may not work correctly with bridges or may not connect at all.
• The IP address should only remain on the bridge; the main interface should not have an IP.

Information Commands

• ifconfig -a — show all interfaces
• brctl show — show bridges
• brctl showmacs — show MAC addresses on bridges

Main brctl Commands

• brctl addbr <bridge> — create a bridge
• brctl delbr <bridge> — delete a bridge
• brctl addif <bridge> <device> — add an interface to the bridge
• brctl delif <bridge> <device> — remove an interface from the bridge
• brctl stp <bridge> {on|off} — enable/disable STP

Configuration Practice

Option 1: Manual Configuration via brctl

1. Disable the interface: ifconfig eth0 down or ifdown eth0.
2. Create a bridge: brctl addbr br0.
3. Add the interface to the bridge: brctl addif br0 eth0.
4. Enable the bridge: ifconfig br0 up or ifup br0.

Option 2: Using Network Manager

            auto br0
            iface br0 inet dhcp
            bridge_ports eno1
            

For static configuration:

            auto br0
            iface br0 inet static
            address 192.168.2.23
            broadcast 192.168.2.255
            netmask 255.255.255.0
            gateway 192.168.2.254
            bridge_ports eno1
            

Option 3: Using Netplan

            network:
              version: 2
              renderer: NetworkManager
              ethernets:
                eth0:
                  dhcp4: no
              bridges:
                br0:
                  dhcp4: yes
                  interfaces:
                    - eth0
            

Notes

• Use netplan try to test the configuration (rollback in 2 minutes).
• Apply settings with netplan apply.