Routing and Switching with Catalyst 3550-48

[Im.The.One]

Ok, so I am still studying and practicing for my CCNA, and am very new to Cisco and only know basic commands and configuring etc. So my boss is wanting me to configure these routers we got for clients of ours as practice. We will be using them with a T1 using an AdTran as the middle man and everything in the AdTran is disabled. What I have been trying to figure out is how I can have 1 cord running from AdTran to port 1 on Cisco, this in my head would be the routing port and allow the rest of the ports to be switch ports... Am I thinking this through properly? If so can someone give a possible lead as to where I could find out how to do this? I have been watching through some of the nuggets that we have and the only one I can find and the one my boss thought would help is more so about VLANS and Trunking rather than the, what seems to be basic setup that we need.

Can anyone shed some light on me to help me out?

[Edwin Summers]

This Cisco document may provide some additional information for you:

http://www.cisco.com/en/US/docs/switches/lan/catalyst3550/software/release/12.1_19_ea1/configuration/guide/swint.html#wp1035057

Depending on how you want to set it up, you are on the right track.  Since the 3550 has layer 3 capability, you can set up routed ports by using the no switchport command from interface configuration mode.  From there, you can assign the port an IP address and so forth.

For the "back end" (LAN) connections you can set up VLANs to separate broadcast domains.  If you configure each VLAN with the appropriate SVI you can route between them as well as through your routed port to the World.

Does this help?  Feel free to follow up with additional questions.

-Ed

[Leo Laohoo]

Not all 3550 can do layer 3.  This will depend on your IOS and/or whether or not you have upgraded the hardware to support Layer 3.

[Edwin Summers]

Oops - thanks for catching that assumption, leolaohoo!

Step 1 - Make sure you have the right hardware and IOS before trying what I suggested above. 

[glen.grant]

  Learn something new everyday ,  can't say I have seen a 3550 that does not route.    I know there were ones that only did like static routing  and the enterprise which ran everything from  ospf to bgp .

[Jeff Van Houten]

Didn't imply the layer 3 switch wouldn't route. What I said was if the adtran is a CSU/dsu that it wouldn't connect to an Ethernet port depending on the model.

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[Leo Laohoo]

Learn something new everyday ,  can't say I have seen a 3550 that does not route.    I know there were ones that only did like static routing  and the enterprise which ran everything from  ospf to bgp .

3550 came in two distinct "flavours":  SMI or EMI.

SMI stands for Standard Multi-Layer Image and EMI stands for Enhanced Multi-Layer Image.  SMI is a layer 2 switch.  If loaded with the correct IOS, 12.2 instead of 12.1, then it can do "limited" routing.

Using a hardware chip, you can upgrade the SMI into an EMI.  The EMI will do routing but I don't know how "far" this will go.  Its got a small memory so I am not really sure if an EMI can do BGP.  I am suspecting OSPF and EIGRP is the most the EMI can do.

[Jeff Van Houten]

Is the Adrtran a CSU/dsu? If so it will have a serial connection that will have to be connected to a router with a serial port and a dce/dte cable. What model adtran is it?

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[Im.The.One]

Well, we are also subcontracted Earthlink techs that install the AdTrans at least 2 or 3 times a week, so I know it is an ethernet connection only, it has a serial port but I have done tons of installs even in large networks and no one really uses them that I have seen. Running version 12.1 the exact image is

flash:c3550-i9k2l2q3-mz.121-20.EA2.bin

We ordered them used, so not sure if anything has been upgraded or not. I know its the 3550-48-SMI.

[Edwin Summers]

Blake,

Were you ever able to get any further with your original question?  Is there anything we can assist with?

[Im.The.One]

You guys have been a big help so far, I am further investigating and talking with my boss about the issues and we are seeing what he wants to do, I will definitely give you guys an update on what goes on. I believe I am going to try and upgrade to 12.2 tonight and play with it a little more and see if I can get it to work. I tried the no switchport command, and while it didn't reject it, I didn't notice a difference either. I tested it and it still worked as a switch instead of a router so we will see after the upgrade tonight! Thanks again for the assistance thus far. You have all been very helpful!