The MX Series routers support two methods of configuring bridge interfaces: enterprise and service provider styles. This article explains each method.

What is the difference between enterprise and service provider style configuration of a bridge interface on an MX Series router?

In the service provider style of configuring a bridge interface, you are required to explicitly configure each feature on the interface, and ensure that the bridge domains reference the interface.

In the enterprise style of configuration, you are not required to explicitly configure each feature, which reduces the amount of configuration but also reduces the number of features.

Refer to the example equivalent configurations below.

Service Provider Style

To configure the bridge interface using the service provider style, you need:

• vlan-tagging

• encapsulation

• unit

Example

interfaces {
       ge-0/0/0 {
            vlan-tagging;
            encapsulation extended-vlan-bridge;
            unit 1 {
                   vlan-id 1;
            }
            unit 2 {
                  vlan-id 2;
            }
      }
      ge-0/0/1 {
           vlan-tagging;
           encapsulation extended-vlan-bridge;
           unit 1 {
                vlan-id 1;
           }
           unit 2 {
                vlan-id 2;
           }
      }
}
bridge-domains {
       VLAN-1 {
               vlan-id 1;
               interface ge-0/0/0.1;
               interface ge-0/0/1.1;
      }
      VLAN-2 {
              vlan-id 2;
              interface ge-0/0/0.2;
              interface ge-0/0/1.2;
      }
} 

Another way to configure bridge interfaces on an interface with different encapsulations is to use the encapsulation "flexible-ethernet-services" under the interface and the encapsulation "vlan-bridge" under the logical unit. In the following configuration, the interface ge-0/0/0.2 is part of the bridge-domain VLAN-2, whereas the interface ge-0/0/0.1 works as an L3 interface.

interfaces {
       ge-0/0/0 {
            vlan-tagging;
            encapsulation flexible-ethernet-services;
            unit 1 {
                   family inet {
                        address 192.51.100.27/31;
                   vlan-id 1;
            }
            unit 2 {
                  encapsulation vlan-bridge;
                  vlan-id 2;
            }
      }
bridge-domains {
      VLAN-2 {
              vlan-id 2;
              interface ge-0/0/0.2;
      }
}

Enterprise Style

To configure a bridge interface by using the enterprise style, you need:

• family

• interface-mode

• vlan-id

Example

interfaces {
     ge-0/0/0 {
          unit 0 {
               family bridge {
                    interface-mode trunk;
                    vlan-id-list [ 1 2 ];
              }
         }
     }
     ge-0/0/1 {
          unit 0 {
               family bridge {
                    interface-mode trunk;
                    vlan-id-list [ 1 2 ];
               }
          }
     }
}
bridge-domains {
     VLAN-1 {
          vlan-id 1;
     }
     VLAN-2 {
         vlan-id 2;
     }
}

Warning: ACX Series routers no longer need configuring a bridge domain by using the service provider style. Such configuration should be replaced with the VLAN hierarchy configuration.

• 2022-12-06: Changed the IP address used in this example to match the documentation standards

• 2022-12-02: Added warning stating ACX Series does not need SP style configuring like MX Series

• 2019-08-23: Added another way to configure bridge interfaces under the Service Provider Style

• 2018-03-14: Corrected values used in configuration example

• Configuring Interface Encapsulation on Logical Interfaces

• KB21581 - MX] How to classify bridged and routed traffic from 'family bridge' interfaces [juniper.net]

• Junos OS MX Series 3D Universal Edge Routers Solutions Guide

• Junos OS for MX Series 3D Universal Edge Routers