Re: LAN Standards Document

Hi,

On Tue, Aug 4, 2009 at 7:25 PM, backbone
systems<backbone.systems_at_gmail.com> wrote:
>
> can anyone shed some light on this topic.....what are the major
> disadvantages of moving ur access switches to layer 3.....performace
> should not be counted at all.....

It doesn't work very well if you have endpoints with statically
assigned IP addresses, because moving a device from one switch to
another typically means changing its IP address. Therefore, it doesn't
really work within the data centre.

I saw one customer try to implement layer 3 uplinks from the access
layer switches in a data centre -- each row of racks was served by a
pair of 'end of row' switches. This meant each row of racks supported
a specific set of IP networks. Equipment is always being shuffled
around inside data centres, so the whole system quickly became
unworkable and they reverted to a more traditional design.

The most common design I see these days is layer 3 in the core and out
to distribution switches, with layer 2 links to the access switches.

cheers,
Dale

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Received on Tue Aug 04 2009 - 19:39:19 ART