[j-nsp] Juniper EX/QFX vlan-id-list limitation

[Olivier Benghozi]

Hi,

We miraculously found this doc before implementing such QinQ conf on EX4600 (that are low end QFX5100).
So we didn't try to test the switch with this case, and we directly used such config: instead of vlan-id-list [some ids], we (nearly) always use the same one everywhere: vlan-id-list 2-4094. Problem fixed before it appeared.

Sometimes we use vlan-id-list 1-4094 and native-vlan 1, when some untagged traffic must be carried too – in this case the untagged traffic is double-tagged on the NNI port with dot1q tag 1 as cvlan – there's a thread about that in this mailing-list by the way.


> Le 12 août 2020 à 18:18, Robin Williams via juniper-nsp <juniper-nsp at puck.nether.net> a écrit :
> 
> Has anyone come across PR1395312 before?
> 
> “On ACX/EX/QFX platforms, if VLAN ID lists are configured under a single physical interface, Q-in-Q might stop working for certain VLAN ID lists”.
> 
> [...]
> 
> interfaces {
>    xe-0/1/0 {
>        flexible-vlan-tagging;
>        encapsulation extended-vlan-bridge;
>        unit 3104 {
>            vlan-id-list [ 1102 1128 1150 1172 4000 4001 4002 4003];
>            input-vlan-map push;
>            output-vlan-map pop;
>        }
> 
> The docs page for ‘vlan-id-lists’ does mention:
> https://www.juniper.net/documentation/en_US/junos/topics/reference/configuration-statement/vlan-id-list-edit-bridge-domains.html
> 
> “WARNING On some EX and QFX Series switches, if VLAN identifier list (vlan-id-list) is used for Q-in-Q tunnelling, you can apply no more than eight VLAN identifier lists to a physical interface.”