Layer 2/3 VLANs Multiple Floor Design Advice

[Ammit]

Hay everyone

   I am new to experimenting with vlans and could do with some some advice. The design I have is three floors of a building, with each floor containing hosts from three different vlans (hr,finance,production)

Currently I have a layer 3 switch with three SVIs, these SVIs have been assigned addresses for routing. These SVIs trunk to three layer 2 switches (each representing a floor, e.g floor 1 switch, floor 2 switch floor 3 switch). From these layer 2 floor switches, there are another three trunked layer 2 switches with each switch having a designated vlan (hr, finance, production).

I have up to 60 hosts on each floor, 20 in each vlan. I am just wondering if this is the correct way of doing this as I am thinking this is quite messy. Any advice would be appreciated thank you.

[Seb Rupik]

Hi there,

Although it would work, it is not a very scalable or cost effective design.

You are better off having a single Layer2 switch per floor, with enough port density of supply every floor (with some % spare for expansion) and have it provide the access ports for all of the business functions (HR, finance, etc).

cheers,

Seb.

[Ammit]

Thanks for the reply, yes I totally agree not cost effective at all, but if I have 60 hosts to a floor wouldn't I need more than just the one switch as they top out at 24 (in packet tracer :) )?

[Seb Rupik]

Yes, two 48 port Layer2 access-layer switches stacked together per floor would be ideal.

Something like a 2960X-48 .

PoE requirement should be your next concern in selecting a specific model.

cheers,

Seb.

[Ammit]

Actually ignore what I said, I just checked out port density, forget about packet tracer, your logic is now sound to me thank you.

[Leo Laohoo]

I've seen a few students ask this questioning for school work.  

The answer to the question will depend on the knowledge of the instructor.  

Inter-floor VLAN is, in some cases, will depend on the industry it's meant for.  Administration and office space will/might benefit as long as the entire building is occupied.  Move the industry to production and manufacturing and inter-floor VLAN is no longer applicable. 

In most cases, VLAN/subnet segmentation is based entirely on the physical building.  Next, there's another option of routing to every building as I can, potentially, re-use the same VLANs as long as there is a CE in every building.