What is the best method to stretch a VLAN trunk across routed links?
I’ve read L2TP-V3 is available or QinQ?
I’m running 3850’s in my lab.
If you only need to get it across a routed link between two switches, L2TPv3 or VXLAN:
Q-in-Q lets you tunnel VLANs over VLAN:
https://networklessons.com/switching/802-1q-tunneling-q-q-configuration-example
You won’t be able to do any of this on your 3850s though. They can do MPLS but I don’t think they can do pseudowires.
Rene
Thanks, Rene.
My 3850’s actually can do Psuedowire if you’re running IPServices. I just don’t know if they support MPLS.
Will MPLS also allow you to stretch a VLAN across routed links? I have a few buildings that are separated by 3850’s with configured routed ports between the buildings to shorten the STP trees.
The whole Plant used to be a single STP instance but we were getting too many issues with STP drops and recalcs which affected our Industrial network devices.
We have Ubiquiti Access Points but they don’t support L3 roaming, only L2 roaming. I wanted to keep a single VLAN for Tablet access but that crosses routed links so I needed a solution for that with the gear we already own.
The 3850s will do L2TPv3 but not vxLAN.
What if I have to hop 3 routes?
Thanks so much for your reply.
Hello Sean
Yes, MPLS is able to span your VLAN across routing links. MPLS is a tunneling mechanism that allows you to tunnel multiple protocol types, including Ethernet. So you can create an L2 tunnel between remote sites and span you VLANs to wherever you want. However, its configuration is somewhat more involved than the other solutions that Rene suggested. If you’re interested, take a look at this introductory lesson to MPLS, as well as a lesson on L2 tunneling using MPLS:
You can use MPLS or L2TPv3 or VXLAN (or any L2 tunneling technology) over multiple router hops. These technologies essentially create a Layer 3 underlay network that can have multiple routers and multiple hops, that allows an L2 tunnel to be created between remote sites, thus allowing you to span your layer 2 network segments across multiple sites.
I hope this has been helpful!
Laz
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My simple lab is this :
I have a L3 switch with all SVIs and VLANs created at the “core” switch. I need my PC to get any VLAN of my choosing.
How do I properly setup the “core” side since I can’t create an inbound interface for the xconnect statement?
From some quick research, it seems the 3850 might support VXLAN since IOS-XE 16.12.5b. That might be worth looking into.
Hello Sean
Take a look at this response:
Laz
Hey dude. Did you happen to read my reply on my thread? I responded to your statements.
Thanks very much for your replies.
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