Enable the following options in the kernel configuration and recompile the kernel if necessary:
Networking support: Y
Networking options:
802.1d Ethernet Bridging: M or Y
In this section we are are going to discuss how to set up a
network bridge using systemd-networkd. In the
examples below, eth0
represents the external interface that is being bridged, while
br0
represents the
bridge interface.
To create a bridge interface, create the following configuration
file by running the following command as the root
user:
cat > /etc/systemd/network/50-br0.netdev << EOF
[NetDev]
Name=br0
Kind=bridge
EOF
To assign a network interface to a bridge, create the following
configuration file by running the following command as the
root
user:
cat > /etc/systemd/network/51-eth0.network << EOF
[Match]
Name=eth0
[Network]
Bridge=br0
EOF
Repeat the process for any other interfaces that need to be bridged. Note that it is important that nothing assigns any addresses to the bridged interfaces. If you are using NetworkManager-1.42.0, make sure you configure them to ignore the bridged interfaces, as well as the bridge interface itself.
If you are on a network which uses DHCP for assigning ip
addresses, create the following configuration file by running the
following command as the root
user:
cat > /etc/systemd/network/60-br0.network << EOF
[Match]
Name=br0
[Network]
DHCP=yes
EOF
Alternatively, if using a static ip setup, create the following
configuration file by running the following command as the
root
user:
cat > /etc/systemd/network/60-br0.network << EOF
[Match]
Name=br0
[Network]
Address=192.168.0.2/24
Gateway=192.168.0.1
DNS=192.168.0.1
EOF
To bring up the bridge interface, simply restart the systemd-networkd daemon by
running the following command as the root
user:
systemctl restart systemd-networkd