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subspace3

join:2013-02-03

[CCNA] Cisco 3 tier design selection

Hi,

Wondering if anyone can help. Got a design to do for 3000 users, all in different rooms connected to 2960's switch stacks. What I want to know is how to connect these to 2x core distribution switches.

First of all there will be 3 vlans, admin,sales, teaching in the design, am I right in saying its not possible for these vlans to span all the access switches? To provide inter vlan routing I was thinking of using SVI'S on each distro switch, just unsure how this would work since there 22 stacks in total, each would have one fibre connection to each distro switch. Can a SVI for lets say vlan sales span multiple switch ports? I'm wondering if its possible for all 22 trunks from the access to connect to one distro switch, and that the distro switch will have 3 SVI's spanning also those ports so it can do intervlan routing?? how would this work with another distro used for redundancy! If any one can explain this to me id be very grateful!

Thank you!

markysharkey
Premium
join:2012-12-20
united kingd

4 edits
The three VLAN's can be across all switches no sweat.
An SVI will be in the same VLAN as any physical interface with the same VLAN-ID, so yes an SVI can span multiple interfaces, but that's not really how or why they work.

You can run it as you mention with all the fibre trunks connected into 1 distri switch which handles the inter VLAN routing duties. This option does not allow for redundancy though. If at all possible I would want two fibres from each switch into the distribution layer. Run both fibres to a single distri switch with Etherchannel or like in the diagram above one fibre to each of a pair of distri switches which are themselves interconnected with a few trunks running Etherchannel. The connections between the disti layer switches are not shown in this diagram, but I would probably run at least 4 Gigabit links between the two disti switches and bundle them with etherchannel.

--
Binary is as easy as 01 10 11

cramer
Premium
join:2007-04-10
Raleigh, NC
kudos:9
reply to subspace3
If your talking about using the L3 capabilities of each 2960 access switch, then no, you cannot put the same SVI L3 routed interface on more than one switch -- you're getting into VRRP/HSRP there. (i.e. 192.168.1.1 cannot be on more than one switch -- VRRP/HSRP still requires unique addresses per member.)

What I did a decade ago with 5500's and RSPs... "MLS" (multi-layer siwtching)... the first packets in a stream have to go all the way to the RSP to be routed; after that, the mls tags allow L3 traffic to be L2 switched. I'm not sure anything still supports this brand of crazy.

HELLFIRE
Premium
join:2009-11-25
kudos:18
reply to subspace3
Is it just me or are we doing someone's CCNA homework here?

said by subspace3:

What I want to know is how to connect these to 2x core distribution switches.

See markysharkey See Profile's diagram below for one possibility.

said by subspace3:

am I right in saying its not possible for these vlans to span all the access switches?

said by subspace3:

Can a SVI for lets say vlan sales span multiple switch ports?

The NA answer is "yes, it can span multiple switches." Go back to the NA labs where you configure
two switches, two VLAN groups on each, and a trunk between them. The real world answer is "depends
what your requirements are."

said by subspace3:

using SVI'S on each distro switch, just unsure how this would work since there 22 stacks in total,

As cramer See Profile says, HSRP / VRRP. IIRC, that wasn't touched until CCNP, which REALLY makes me wonder
what this has to do with CCNA?

said by subspace3:

I'm wondering if its possible for all 22 trunks from the access to connect to one distro switch,

NA answer and real world answer is "Yes." The long answer is "see a 356x / 375x / 45xx / 65xx series device."

Seriously, subspace3 See Profile, you sure this is for CCNA, or are you just skipping ahead, because I'm wondering
if you even have the concepts of trunking and VLANs down from NA yet?

Regards

markysharkey
Premium
join:2012-12-20
united kingd
reply to subspace3
quote:
As cramer See Profile says, HSRP / VRRP. IIRC, that wasn't touched until CCNP, which REALLY makes me wonder
what this has to do with CCNA?
I was thinking the stack master would have the SVI to save having a large group of SVI's and "losing" a load of IP addresses inside a large subnet or three.
I really like HSRP / VRRP / GLBP. So simple, but so powerful
--
Binary is as easy as 01 10 11