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how to route with a 3550-12G?

I'm not *entirely* certain how to proceed here as I haven't done anything quite like this before, but I will describe what I have and hopefully someone can answer my questions.

I have a brand new site. The LAN there will be on the network. at all our older sites the .1 address is reserved for the gateway router. I have four IDF's that will aggregate in a 3550-12G on Interface Gig1-4

Interface Gig8-10 are reserved for servers with addresses .32 and .34. Gig 11 is going to be for the wireless shot out of the building and it has to be on the network. There is no router here. I have to get the data out of the building on the 3550 and this is where I get lost.

My questions are:

1) How do I create VLAN(x) and put Gig 1-10 on it? I use the x variable because I'm not sure if I should just use as the address of VLAN1 and let those ports be a part of that by default, or do I need to create a different VLAN and make those ports a part of the "new" VLAN? If I do that do I even need an IP address on VLAN 1?

2) How do I get all the traffic destined for the WAN to pass from those ports on VLAN(x)to VLAN(y) on Gig11? I'm unsure of the commands I need to route between VLAN's without using an actual router.

3) How do I do this and still have the default gateway on all my WIntel machines be

4) Do I need to put something akin to " ip route Gig11" on VLAN(x) in order to pass the traffic destined to other networks?

Whatever else you can tell me. I'm kinda new to this L3 switching thing.


New Member

Re: how to route with a 3550-12G?

Hello Mattew, are you from Stafford, England? Because I'm from Stoke on Trent, England - not far at all!

Anyway, in response to your queires, see my opinions/advice below:

1) You need to create a VLAN here. I would go to config mode and type: interface vlan 1 (Enter) This will put you in interface mode for VLAN 1. You then need to enter the IP address of the default gateway for this VLAN which in your case is All ports assigned to this VLAN will send traffic for inter-sunet devices (outside it's own subnet) to this address for routing. Next you need to assign port 1-10 to VLAN 1.

2) Because the subnet is directly connected the 3500 should route frames to this destination by default.

3) Yes, have all devices on VLAN 1 (ie ports 1-10) configured with a default gateway of the VLAN 1 IP address. From here it will be routed.

4) If the traffic is destined for subnets directly attached you don't need any further commands. If the destination IP subnet is remote from the switch you will need to enter a defualt route as you suggested.

Hope some of this helps.


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