A bridge domain is a logical grouping of one or more ports that forwarding traffic between those ports. Bridge domains can be configured with Layer 2 (L2) and Layer 3 (L3) attributes. All ports within the same bridge domain must have the same L2 attributes. L3 attributes can be different for each port, but all ports within the same bridge domain will use the same L3 gateway.
Another use case for a bridge domain is to provide connectivity between two networks that use different Layer 3 protocols. For example, a bridge domain could be used to connect an IPv4 network to an IPv6 network. In this case, the bridge domain would be configured with L3 attributes (IPv4 address, IPv6 address, etc.) to allow traffic to flow between the two networks.
Bridge domains can be configured using the Cisco Application Centric Infrastructure (ACI) controller. The ACI controller provides a graphical user interface (GUI) and a command-line interface (CLI) for configuring bridge domains.
In the GUI, navigate to the Bridge Domains page to configure a new bridge domain. Enter the desired name for the bridge domain and click the Create button.
In the Bridge Domain Details page, configure the L2 and L3 attributes for the bridge domain. Click the Save button to save the changes.
In the CLI, use the following commands to configure a bridge domain:
The parameter is the name of the bridge domain. The and parameters are the L2 and L3 attributes for the bridge domain, respectively.
After the bridge domain is created, ports can be added to the bridge domain. In the GUI, navigate to the Ports page and select the ports that you want to add to the bridge domain. Click the Add to Bridge Domain button and select the desired bridge domain from the drop-down menu.
In the CLI, use the following command to add a port to a bridge domain:
The and parameters are the name of the bridge domain and the port, respectively.