Re: interface Vlan vs L3 port switch

Do I understand the topology like this:

L3port-SW1 <-> L2-SW2 <-> L3port-SW3

Having any L3 device connect to your L2 switch is fine.

Having two L3 devices connecting to your L2 switch and configuring these
ports within the same VLAN means that they can talk just fine ;-)

I would suggest to use portfast on the interfaces connecting to the L3
devices. You may also consider bpdufilter as well as a default for when
using portfast.

Is it a good design in your network? Humm ... you would know best.

HTH,

Andrew

.
On Wed, May 18, 2011 at 2:42 AM, <fferrer10_at_gmail.com> wrote:

> Hi Guys,
>
> I have some doubts about a config a colleague of me is doing using L3
> Catalyst
> switches: in order to have IP communication on 2 linked switches, he is
> using a
> L3 port on each one, and conecting this port (with a cable) to a L2 port of
> a
> common vlan (in each switch)... As the vlan crosses the switches and has L2
> ports on each one, he can connect another L3 port, with the same ip
> network, to
> a port of the second switch and have the 2 switches speaking IP in this
> vlan
>
> My first impression was "this can be or could be a potential loop, why not
> using the Vlan interface, that is done for this cases?"... Anyway, since he
> told me that is plannig to run BGP and he does not like a vlan interface
> as
> bgp speaker, i am wondering if there are reasons to totally reject this
> strange/curious design.
>
> Anyone can provide help to see the possible problems of this scenario on a
> production environment, please?
>
> TIA and best regards.
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
>
>
>
>
>
>
>

-- 
Andrew Lee Lissitz
all.from.nj_at_gmail.com
Blogs and organic groups at http://www.ccie.net