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VMAN and Jumbo-Frame Question(s)

VMAN and Jumbo-Frame Question(s)

I'm faced with having to configure a VMAN for one of our customers between two of our data centers in different cities. The current setup is Edge(460) <-> BD8806 <- metro link -> BD8806 <-> Edge(460)

Reading up in a hurry (of course - does it ever happen otherwise?), I hand off an untagged port to the customer on the edge switch, VMAN/tagged ports on all other switches that are involved, and enable jumbo frames on all ports involved. Does that sound about right?

My questions are:
- Is it a good idea to create one VMAN per customer who wants/needs that, or is there some VMAN "sharing" that should rather be done for all customers that are being carried between the two cities (but aren't supposed to see each other's traffic)?
- Do I also have to enable jumbo frames on the edge switch port (handoff to customer)
- The metro link port that connects the BD8806s between two cities, it can be part of regular VLANs as well as VMANs, correct?

On Jumbo-frames:
- If a customer device connected to the edge switch doesn't support jumbo frames, will the edge switch just "handle it"?
- is there a disadvantage to transporting standard-size MTU traffic over jumbo-frame enabled ports? Let's say I have a vlan where the access ports are on an edge switch, but I need to route/transport the traffic over the jumbo-enabled metro link port (via vlan, not vman), are there issues?

Sorry for the many questions, and yes, I've cross-read through the documentation, but I haven't found the answers (yet), or I may have read them but missed them as answers due to my lack of fully understanding the concepts.

Thank you all for your help!


Extreme Employee
Glad to hear things are working!

Of course "we" just added another wrinkle. (Exos
Customer wants to also get his STP across the link - as far as I know, since 15.5 you need to tunnel that.

From what I see, I need to create an l2pt profile, "add protocol filter stp action tunnel" (stp is already predefined in - and do I need to specify 'encaps' anywhere?

Now, adding that profile to the vman, I think I need to add both the untagged port where the customer plugs their switch in, as well as the uplink port to my 8800, right?
Like : config vman test ports 3,55 l2pt profile allow-stp

Now, do I have to add l2pt profiles to the 8800s as well and add all the proper ports to the vman configuration on the 8800s, or do I not have to worry about it on the in-between switches, because everything's already encapsulated and firmly inside the vman?

Thanks again!

Nevermind. Typos screw things up - VMAN works well now, transporting the customer VLANs across as advertised, and it appears that STP works across the link as well - not that I know how (because I'm not doing l2pt), but it's Monday and I take any victory 😉

Extreme Employee


1. I would suggest one VMAN per customer, this is becuase the VMAN is the broadcast domain and if you want to make sure there is a clear delineation of traffic one VMAN per customer.

2. Enable jumbo frames on all ports on your side. Doesn't matter on customer but I would suggest jumbo-frames their too.

3. Configuration on your end, tagged VMAN's all the way through your core.

4. Jumbo frames will not be a problem, enable them on all of your ports and your good to go.

5. You also need to configure the ethertype for the VMAN too... "configure vman ethertype 0x8100"

Let me know if there are any other questions...