STP Configuration

STP (802.1D) Configuration

To enable STP on a bridge by run the following command:
$ ip link set dev br0 type bridge stp_state 1
By default, STP is disabled.
To disable STP on the bridge set stp_state to “0”. To show the current stp_state value, run the following command can be used:
$ ip -d link show dev br0 | grep stp_state
In addition, to show extended STP configuration on the bridge (bridge stp state, port stp state, …), you can use brctl utility.
$ brctl showstp br0
You can use brctl to configure the following spanning tree protocol parameters:

• Bridge priority
• Path priority and cost
• Forwarding delay
• Hello time
• Max age
  For an explanation of these parameters, see the IEEE 802.1d specification. See brctl man for details on bridge stp configurations.

RSTP (802.1w) configuration

RSTP support requires user-level daemon mstpd, running in RSTP mode. The mstpd daemon is an open source project (https://github.com/mstpd/mstpd). The mstpctl utility provided by the mstpd service configures STP.

After the bridge is created and STP is enabled (described above) additional configuration step needed to switch from STP to RSTP mode.

Switch the bridge mode from stp to rstp using the mstpctl application:
$ mstpctl setforcevers br0 rstp
To show information about the bridge:
$ mstpctl setforcevers br0 rstp
To show port information:
$ mstpctl showport br0 sw1p5
See mstpctl man for more information.