Bridge Domain Configuration on Juniper MX

For example, on Cisco switches and other manufacturers, in order for traffic of one or more vlans to go between ports, you just need to specify the necessary VLANs on these ports, on Juniper, in addition to configuring ports, you also need to add these ports to the bridge domain, without this traffic between ports will not go.

For example, I use Juniper MX204, first we configure the ports with the tags of the required vlan:

set interfaces et-0/0/0 vlan-tagging
set interfaces et-0/0/0 encapsulation extended-vlan-bridge
set interfaces et-0/0/0 unit 500 vlan-id 500

set interfaces et-0/0/1 vlan-tagging
set interfaces et-0/0/1 encapsulation extended-vlan-bridge
set interfaces et-0/0/1 unit 500 vlan-id 500
show
show interfaces

An example of setting up an access port:

set interfaces et-0/0/3 encapsulation ethernet-bridge
set interfaces et-0/0/3 unit 0 family bridge

An example of setting up an L3 interface:

set interfaces irb unit 500 family inet address 192.168.5.5/24

Now let’s configure the bridge domain by naming it “ixnfo-com-vlan-500” and add the necessary interfaces to it:

set bridge-domains ixnfo-com-vlan-500 domain-type bridge
set bridge-domains ixnfo-com-vlan-500 vlan-id 500
set bridge-domains ixnfo-com-vlan-500 interface et-0/0/0.500
set bridge-domains ixnfo-com-vlan-500 interface et-0/0/1.500
set bridge-domains ixnfo-com-vlan-500 interface et-0/0/3.0
set bridge-domains ixnfo-com-vlan-500 routing-interface irb.500

Check the created bridge domain:

show bridge-domains
run show bridge domain

Similarly, you can create more bridge domains for the remaining ports and with repeated vlans that will be independent.

Let’s check the correctness of the configuration and apply:

commit check
commit

After creating the bridge domain, you can look at the MAC addresses in it:

run show bridge mac-table

I will give a simple example of editing the configuration, for example, we will remove the access interface et-0/0/3.0 from the bridge domain configuration and re-add it (all changes will be applied only after the commit command is executed):

edit bridge-domains
show
edit ixnfo-com-vlan-500
show
delete interface et-0/0/3.0
set interface et-0/0/3.0
show
exit

See also my article:
Juniper MX204 setup