Configure Cisco Catalyst 3550

[drich06]

Hi,

So this is my very first time configuring a switch. I was given the task to replace a few 10/100 switches with this cisco catalyst 3550 switch. I created 3 vlans for the on the switch (vlan 10 0-16, vlan20 17-32, vlan 30 33-44) ports 45 to 48 are defaulted to vlan 1.

The request is to connect the cisco switch directly to their ISP (They do not have another independent router at the moment).

What configuration would i need to do to the router which is a layer 2 in order for it to get internet access from the ISP's router?

[arshadudddin]

Hello,

You need a Layer 3 Switch.

[drich06]

I was only provided with one switch

[balaji.bandi]

First, you needd to configure switch act as Layer3 for inter-VLAN routing and configuring more vlan: follow the below example :

https://www.cisco.com/c/en/us/support/docs/lan-switching/inter-vlan-routing/41860-howto-L3-intervlanrouting.html

What configuration would i need to do to the router which is a layer 2 in order for it to get internet access from the ISP's router?

Router always in Routed mode (until configured different bridge mode) - what Router do you have ISP?

Do you have access to ISP router, so you need to configure Static Routing back to switch, and configure NAT for the internal subnet you configuring VLAN 10 20 and 30.

[MHM Cisco World]

Catalyst 3550 
NOT support NAT and this need for internet 
so you cannot use this SW and connect it directly to internet, you need router inbetween.  

[drich06]

What configuration would i need to do to the router which is a layer 2 in order for it to get internet access from the ISP's router?

It shouldve been what configuration would i need to do to the switch.

[MHM Cisco World]

Friend NAT 
you can not access internet with your private LAN. 
your SW platform not support NAT so you need router 

[Joseph W. Doherty]

A 3550!?

What to do would depend on what your ISP can do (for you).  As the other posters have noted, usually you need some kind of L3 capable device which supports NAT, which I don't recall either the 3550-SMI or 3550-EMI supported.

If you're wanting to replace 10/100 switches using gig port 3550, I'm guessing funding is tight to non-existent.  Even so, you would likely be much better offer finding something newer than a 3550; which doesn't cost a fortune.  (BTW, Cisco's SMB series switches and/or routers are often much lower priced than Cisco's Enterprise class of switches and routers.  The SMB series likely offers about 90% of the features everyone really needs/uses, the Enterprise class supports advanced/exotic features.)