Re: Native VLAN id on Juniper

set vlans VLAN_100 vlan-id 100
set vlans VLAN_200 vlan-id 200== CASE 1

set interfaces ge-0/0/0 unit 0 family ethernet-switching port-mode trunk
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members all

OR

set interfaces ge-0/0/0 unit 0 family ethernet-switching port-mode trunk
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members VLAN_100
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members VLAN_200

lab@switch# run show vlans
Name           Tag     Interfaces
VLAN_100       100
                       ge-0/0/0.0*
VLAN_200       200
                       ge-0/0/0.0*

Traffic from/to VLAN_100 sent/received on ge-0/0/0 is tagged.== CASE 2

set interfaces ge-0/0/0 unit 0 family ethernet-switching port-mode trunk
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members all
set interfaces ge-0/0/0 unit 0 family ethernet-switching native-vlan-id VLAN_100

OR

set interfaces ge-0/0/0 unit 0 family ethernet-switching port-mode trunk
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members VLAN_100
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members VLAN_200
set interfaces ge-0/0/0 unit 0 family ethernet-switching native-vlan-id VLAN_100

lab@switch# run show vlans
Name           Tag     Interfaces
VLAN_100       100
                       ge-0/0/0.0*
VLAN_200       200
                       ge-0/0/0.0*

Traffic from VLAN_100 sent over ge-0/0/0 is tagged. Received traffic can be tagged with ID 100 or not tagged. 
Either way it will be classified as traffic destined to VLAN_100.

=== CASE 3

set interfaces ge-0/0/0 unit 0 family ethernet-switching port-mode trunk
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members VLAN_200
set interfaces ge-0/0/0 unit 0 family ethernet-switching native-vlan-id VLAN_100

lab@switch# run show vlans
Name           Tag     Interfaces
VLAN_100       100
                       ge-0/0/0.0*
VLAN_200       200
                       ge-0/0/0.0*

Traffic from/to VLAN_100 sent/received on ge-0/0/0 is not tagged.

== CASE 4

set interfaces ge-0/0/0 unit 0 family ethernet-switching port-mode trunk
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members VLAN_100
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members VLAN_200
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members default

COMMIT ERROR

set interfaces ge-0/0/0 unit 0 family ethernet-switching port-mode trunk
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members VLAN_100
set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members VLAN_200
set interfaces ge-0/0/0 unit 0 family ethernet-switching native-vlan-id default

Traffic from/to default vlan sent/received on ge-0/0/0 is not tagged.

== CASE 5

set vlans default vlan-id 300

Behavior of default vlan is the same as any other user configured vlan (CASE 1-3).

Regards, Wojtek