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New Member

Routing between Routers and Layer 3 Switch

I have a 2600(ISP1) router which is connected to Fa1 of 2948G and a 3600(ISP2) connected to Fa2 of 2948G. The port Gig49 is connected to 3500 switch (group 1 for ISP1) and Gig50 to another 3500 switch (group 2 for ISP2). The first thing that I did was use the 2948G as a layer 2 switch and it worked out fine. My question is I want to use the 2948G as a layer 3 switch to maximize its potential but with the same topology. I only have 2 IP blocks for two different ISPs (ISP 1 and ISP 2). What should be my next step?, I configure the 2948G with IP uplink-redirect, and my problem was all my workstations and servers won't go thru to the internet. Please see attachements for reference of my physical topology. I'm a little confused with the routing protocol that will be used. Kindly guide me with this..A little help or advise is much highly appreciated.


Re: Routing between Routers and Layer 3 Switch

Setup distinct vlans for each inbound ISP connection from the routers to the L3. Configure the uplink ports to be members of their respective vlans. Enable a routing protocol on the L3 switch, and allow it to route traffic based on your needs (load balance the links, preferential routing, etc). You will have to do some cleanup on the VTP setup and ensure that vlans are propegating fine across all devices, but it should be a relatively simple operation to get where you want to be.

Hope that gives you a little nudge in the right direction.

New Member

Re: Routing between Routers and Layer 3 Switch

Is it possible to use the 2948G-L3 as layer 2 and layer 3 switch at the same time? Let say i want to assign the first 24 ports to be a layer 2 switch and the last 24 ports to be a layer 3 switch. So that if i have another ISP i'll just plug it in on the remaining 24 ports.