Layer 2 vs. Layer 3 to TOR

Chuck Anderson cra at WPI.EDU
Wed Nov 18 15:43:49 UTC 2009

On Wed, Nov 18, 2009 at 04:34:11PM +0200, Eugeniu Patrascu wrote:
> On Wed, Nov 18, 2009 at 4:04 PM, Kinkie <gkinkie at> wrote:
> > On Thu, Nov 12, 2009 at 9:40 PM, Bulger, Tim <Tim_Bulger at> wrote:
> >> If you use stackable switches, you can stack across cabinets (up to 3 with 1 meter Cisco 3750 Stackwise), and uplink on the ends.  It's a pretty solid layout if you plan your port needs properly based on NIC density and cabinet size, plus you can cable cleanly to an adjacent cabinet's switch if necessary.
> >
> >
> >
> > Juniper claims their switches can do clustering using ethernet
> > cabling, yet a cluster behaves as a single-system-image
> > configuration-wise. Should allow for very flexible cabling and
> > operations-wise for TOR switches. I have never tried it however.
> >
> The Ex4200 can be stacked by the ethernet expansion ports, either 4 x
> 1G or 2 x 10G.
> And yes, it behaves as single switch with multiple line cards.

Yes, up to 10 EX4200 switches can be interconnected into a "Virtual 
Chassis" using either the rear Virtual Chassis Ports (32 Gbps ingress 
+ 32 Gbps egress for each of the 2 ports) with up to 5-meter VCP 
cables, or using SFP, XFP or SFP+ fiber links (not sure if it works 
with copper SFP, but might).  You can mix/match each type of 
interconnection within the same VC.

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