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10

What is the functional difference between these two TPID values? 0x8100 This TPID is used in 802.1Q - its your average, everyday VLAN tagging. A common use for VLANs is for enterprises to organize their network into functional groups (like research, finance, or management). 0x88a8 This TPID is used in 802.1ad - its used for provider bridging (also known as ...


9

VLANs themselves don't advertise. The services running on the VLANs might. Simply extending existing production VLANs across the VPLS link might propagate "garbage" (esp. unwanted broadcasts), so best practice is to use a routed L3 (IP) link or a dedicated L2 link (with a limited number of nodes in the broadcast domain). Each VLAN is only linked to the VLAN ...


7

Responding to individual concerns in the post... Regarding Path MTU Discovery Ideally i would be relying on Path MTU discovery. But since the ethernet packets being generated are too large for any other machine to receive, there is no opportunity for IP Packet too big fragmentation messages to be returned Based on your diagram, I agree that PMTUD cannot ...


6

Sadly the EX4200 (or any EX) is not able to do this. You would need a separate logical unit for the VLAN which has its own VLAN counters. This works for example on Junipers MX routers but not on EX. What you can do however is count the packets and bytes with a firewall filter. I have an working example here, for VLANS 14, 571, 572. You can of course use ...


4

You're correct. The usual service is that the client-side frames are encapsulated at the network edge within service-side frames which then appear as usual 802.1q frames to other switches within the service provider. A de-encapsulation occurs at the far network edge, and the client-set VLAN tags are presented at the client-facing interface. Having said this,...


4

This should do what you are after: set interfaces ge-0/0/0 unit 0 family ethernet-switching port-mode access set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members SVID4 set interfaces ge-0/0/0 unit 0 family ethernet-switching vlan members SVID5 set vlans SVID4 vlan-id 4 set vlans SVID4 dot1q-tunneling customer-vlans 41-42 ...


4

Q-in-Q on the 4200 is super non-intuitive, but here is the configuration that will work for you: If you're mixing Q-in-Q and dot1q, you need to set the dot1q tunnelling ethertype to be 0x8100 set ethernet-switching-options dot1q-tunneling ether-type 0x8100 Now, configure the interface you'll be receiving the C-TAGs on - note that you will only configure ...


4

Can I use QinQ over VXLAN? This would make my life easy as I could assign a SVLAN to each office and be done with it. Yes. We're doing Q-in-Q on DCS-7150S-24's currently running EOS-4.20.11.1M. One thing I noticed when comparing our configs with yours is that your Vxlan1 interface does not have a flood VTEP defined for VLAN 500, just a VNI and a generic ...


4

Routers have physical interfaces that match the media they are connected to. So a router connected to an Ethernet link that is using Q-in-Q would normally have the correct configuration (and logical interfaces) to match the VLANs it will route. A misconfigured router would likely drop the frame, as it would be unable to interpret it.


3

Yes it is supported - please see the answer here (for EX4200, but same behaviour can be expected on EX4550): Juniper EX4200 QinQ question


3

I can attempt to answer your conceptual question. I can't find an actual quote, but it seems pretty clear that .1ad and .1q were never intended to be processed by PCs or other end-hosts. They are (usually) processed by infrastructure equipment only. I don't know what was in the designers minds, but it's hard to imagine QinQ packets going to a PC in a ...


3

Sounds like you need "Selective Q-in-Q" documented here E.g. interface GigabitEthernet1/23 switchport mode trunk switchport vlan mapping 21 dot1q-tunnel 211 switchport vlan mapping 31 dot1q-tunnel 311


3

QinQ is a method to tag already tagged frames with an outer frame. It is like a layer-2 tunneling on a trunk. Selective QinQ allows you to tag some of the tagged frames, but not others.


3

As QinQ is ISP feature the key was in Not in Use entservice license state: show license all ... StoreIndex: 1 Feature: entservices Version: 1.0 License Type: PermanentRightToUse License State: Active, Not in Use, EULA accepted License Count: Non-Counted ... #configure terminal #(config)#license boot level entservices ! #reload Just After ...


2

One way you could do this: Given the following two interfaces: interfaces { ge-1/0/1 { flexible-vlan-tagging; encapsulation flexible-ethernet-services; unit 1 { encapsulation vlan-bridge; vlan-tags outer 1 inner 600; } } ge-1/0/2 { flexible-vlan-tagging; encapsulation ...


2

VPN links are usually L3 point-to-point routed links which is a much more efficient approach. For Q or QinQ tags to work you'd need L2 VPN and generally, that's not a good solution. L2 forwards broadcasts and other unwanted traffic across the VPN links and wastes bandwidth. WAN links only support tags when that service is explicitly part of the plan. ...


1

the basic way is to use ping with the don't fragment bit set to ping with various packet size until you find the correct value: On a Mac OS system use ping -D -s <packetsize> <pingable IP accross the tunnel> On Windows ping -f -l <packetsize> <pingable IP accross the tunnel> On linux, the Don't Fragment bit is set by default: ...


1

The issue is flexible-vlan-tagging is enabled on the port so each logical interface expects a VLAN ID. In your case unit 0 is created without a VLAN specified for that logical unit. The logical interface on which untagged packets are to be received must be configured with the same native VLAN ID as that configured on the physical interface. To configure ...


1

I could not quite understand what you need. Do you want, for example, that VLAN1 and VLAN2 clients do not talk to each other? There is no way to perform vlans throughput unless you perform an LACP on the final miles. What you can say is that the circuit will be transparent, and that VLAN2 clients will only talk to VLAN1 if there was L3 (Routing) equipment ...


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