[j-nsp] Trunking routed vlan interfaces on a Juniper mx960

[Nilesh Khambal]

Hi Dave,

You still need a bridge-domain with matching vlan-id configured. What interface-mode does is when you add a vlan under a interface with "interface-mode access" or in vlan-id-list under "interface-mode trunk", it will automatically associate that interface with the bridge-domain that you have already configured with same vlan-id. You don't have to manually go and add interface under bridge. The association is dynamic.

Here is an example.

[edit]
lab at lumos-re0# show interfaces ge-1/1/2
unit 0 {
    family bridge {
        interface-mode access;
        vlan-id 400;
    }
}

[edit]
lab at lumos-re0# show interfaces ge-1/1/3
unit 0 {
    family bridge {
        interface-mode trunk;
        vlan-id-list [ 400 500 ];
    }
}

[edit]
lab at lumos-re0#

lab at lumos-re0# show bridge-domains vlan-400
domain-type bridge;
vlan-id 400;

[edit]
lab at lumos-re0# show bridge-domains vlan-500
domain-type bridge;
vlan-id 500;

[edit]
lab at lumos-re0#

Here with the show command below, you can see that ge-1/1/2 is part of bridge "vlan-400" which is already configured with vlan-id 400. This is an access port. While interface ge-1/1/3 is part of both bridges vlan-400 and vlan-500. This is a trunk port.

lab at lumos-re0> show bridge domain vlan-400

Routing instance        Bridge domain            VLAN ID     Interfaces
default-switch          vlan-400                 400
                                                             ge-1/1/2.0
                                                             ge-1/1/3.0

lab at lumos-re0> show bridge domain vlan-500

Routing instance        Bridge domain            VLAN ID     Interfaces
default-switch          vlan-500                 500
                                                             ge-1/1/3.0

lab at lumos-re0>

Now, if I have to mix the old-style configuration here, here is how I can do it. I take a new interface and add 2 logical units in it. Each unit is configured with a unique vlan-id.

lab at lumos-re0# show interfaces ge-1/1/4
flexible-vlan-tagging;
encapsulation flexible-ethernet-services;
unit 0 {
    encapsulation vlan-bridge;
    vlan-id 400;
}
unit 1 {
    encapsulation vlan-bridge;
    vlan-id 500;
}

[edit]
lab at lumos-re0#

With old style, now I have to go and manually associate interfaces to their respective bridge domains which are meant for those 2 vlans.

[edit]
lab at lumos-re0# show bridge-domains
<...>
vlan-400 {
    domain-type bridge;
    vlan-id 400;
    interface ge-1/1/4.0;  <<<<<<<
}
vlan-500 {
    domain-type bridge;
    vlan-id 500;
    interface ge-1/1/4.1; <<<<<<<
}
<...>

Now if I run the same show command again, I will see both old style and new style interfaces configured under respective bridges.

lab at lumos-re0> show bridge domain vlan-400

Routing instance        Bridge domain            VLAN ID     Interfaces
default-switch          vlan-400                 400
                                                             ge-1/1/2.0
                                                             ge-1/1/3.0
                                                             ge-1/1/4.0  <<<<<<<

lab at lumos-re0>

lab at lumos-re0> show bridge domain vlan-500

Routing instance        Bridge domain            VLAN ID     Interfaces
default-switch          vlan-500                 500
                                                             ge-1/1/3.0
                                                             ge-1/1/4.1 <<<<<<<

lab at lumos-re0>

HTH,

Thanks,
Nilesh.





On 8/21/09 4:28 PM, "Dave Diller" <dave at maxgigapop.net> wrote:

> Interface-mode knob is more user-friendly in that, when you
> configure it in access or trunk mode with either vlan-id or vlan-id-
> list respectively, the interface is automatically  associated with
> the corresponding bridge-domain.

That's interesting, I didn't have that experience, and I just
coincidentally tried it an hour ago on 9.5R1.8.

I added a new vlan 555 to two trunked interfaces:

unit 0 {
     family bridge {
         interface-mode trunk;
         vlan-id-list [ 104 555 ];
     }
}

but I could not ping across until I manually added it to the bridge-
domain:

dave at lab-MX480> show configuration bridge-domains
test {
     vlan-id-list [ 101-106 555 ];
}

Do I need some magic sauce to allow it to automatically associate?

-dd