Owners Manual
Layer 2 bridging
OpenSwitch OPX supports Layer 2 bridging and includes VLAN bridging, spanning-tree provisioning (STP), link layer discovery protocol
(LLDP), and media access control (MAC) address forwarding. OpenSwitch OPX provides a CPS data model for conguring and managing
the MAC address forwarding database using the CPS API.
You can congure Layer 2 MAC addresses and VLAN learning and forwarding properties in support of Layer 2 bridging. The device learns
unicast MAC addresses to avoid ooding the packets to all the ports in a bridge domain. If the bridge receives a control protocol data unit
(PDU) which does not have a corresponding protocol congured, the control PDU is considered as an unknown multicast data packet, and
the packets are ooded across all ports that are part of the same bridge domain. If the bridge has the protocol corresponding to the PDU
congured, the control PDU is considered as a control packet and is processed by the routing engine.
See the OpenSwitch OPX Developers Guide for more information on writing applications that access the CPS API to congure Layer 2, and
using YANG models to congure the MAC address forwarding database.
Topics:
• VLAN bridging
• Link layer discovery protocol
• Spanning-tree provisioning
VLAN bridging
OpenSwitch OPX supports Layer 2 VLAN bridging by modeling each NPU VLAN entity as a separate Linux bridge instance. Each physical
or LAG port that is a VLAN member is modeled by adding its corresponding Linux interface to the bridge instance. See Application
examples in the OpenSwitch OPX Developers Guide for more information on creating a VLAN and assigning members.
To create a VLAN using the Linux bridge, create the bridge instance and then add a tagged member to the new bridge instance.
OpenSwitch OPX determines the VLAN ID associated with each bridge instance using the VLAN ID of the rst tagged member port
assigned to the bridge instance. The VLAN is created only after you add the rst tagged member to the bridge.
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