Bridge two ports#

You will end up with two physical ports in one layer-2 segment, sharing one address. The usual reasons are a router with more ports than segments, and a spare port used as a one-device switch.

Before you start#

• The operator role and a licence.
• Console access, or a session that does not arrive on either port. Moving an address onto a bridge takes the address off the port it was on, which ends any session using it.

Step 1 — Create the bridge with its first member#

Network → Interfaces → + Add interface, type Bridge.

set interfaces bridge br0 member interface eth2
set interfaces bridge br0 address 192.0.2.1/24
set interfaces bridge br0 description 'lan'

The panel names it br0 by default and takes one member. Add the rest afterwards, one line each:

set interfaces bridge br0 member interface eth3

Step 2 — Move the address#

If one of the members already carries the address the segment uses, delete it from the port in the same commit as adding it to the bridge. An address on a bridge member and on the bridge is a configuration the router will accept and the network will not enjoy.

delete interfaces ethernet eth2 address 192.0.2.1/24

The interface panel removes addresses one at a time and stages the delete.

Step 3 — Move everything that named the port#

Anything that referenced the member interface by name now needs to reference br0.

Missing one of these is the usual reason a bridge "does not work": the segment is fine and one rule still names a port that no longer has an address.

Check it worked#

show interfaces bridge br0
bridge link show

The Interfaces page shows the bridge with its live link state and counters. A member with no traffic on it is usually a cable, and a bridge with no address is usually the step above that was skipped.

Then, from a client on each port:

ping -c 3 192.0.2.1

Both ports should reach the router, and each other.

Undoing it#

delete interfaces bridge br0
set interfaces ethernet eth2 address 192.0.2.1/24

Put the address back where it was in the same commit, and put back everything from step 3.

See also#

• Add a VLAN
• Bond two ports
• Adding an interface
• The interface panel

Checked against ui/src/pages/Interfaces.tsx · agent/main.go