Ok, let me see if I can simply this:

A post that Jens Neelsen made says "a layer3 switch (e.g.3550-EMI) does not
have layer3 interfaces. All interfaces (Fastethernet and GigabitEthernet)
are layer2
interfaces. They can not have IP addresses." Further he adds "The VLANs are
the (virtual) interfaces to the routing engine (=layer3 switch). Layer2
interfaces are grouped into different VLANs and the Layer3 switch (=Router)
enables the communications between these VLANs. "

Ok then the question is - if you have a LAN with ALL switches and NO
routers - how do you define a gateway on the client?

Example:

2 L2 switches. All hosts on switch 1 are in IP subnet 192.168.1.0/24 and all
hosts on switch 2 are in IP subnet 192.168.2.0/24. Both L2 switches are
connected to a single L3 switch with a router engine in it.

Where do you define the gateways at? In order for hosts on L2 switch 1 to
communicate with hosts L2 switch 2, the client has to have a gateway to
forward to correct??

Stephen



----- Original Message -----
From: "Priscilla Oppenheimer" 
To: 
Sent: Monday, February 17, 2003 4:45 PM
Subject: RE: Understanding VLANs - how they remove the physical [7:63173]


> Stephen Hoover wrote:
> >
> > back to switch A to get his routing to
> > the servers?
> > Why would you EVER want a network configured this way?? Or even
> > worse, what
> > if your respective gateway was 3 or 4 L3 switches away?
>
> Your gateway can't be any L3 switches (routers) away. It has to be on your
> LAN. It has to be in your subnet. It has to be in your broadcast domain.
It
> has to be in your VLAN. For one thing, a host ARPs for its default
gateway.
> ARP uses broadcast.
>
> I just noticed your comment and wanted to add my comment. Without being
able
> to decode your drawing, it's hard to tell exactly how to answer, but I'm
> just trying to get you to think about what really happens to packets on a
> campus network. The network design you're considering isn't just
> impractical. It won't work, if I understand it correctly.
>
> Priscilla
>
>
>
> > That
> > just doesn't
> > seem practical to me.
> >
> >
> > Thanks!
> > Stephen Hoover
> > Dallas, Texas




Message Posted at:
http://www.groupstudy.com/form/read.php?f=7&i=63194&t=63194
--------------------------------------------------
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]

Reply via email to