I am going to buy a couple of 2950's for a test lab. Will I need a SI or EI switch? Obviously price is a concern, so if I can get away with the SI I will. CCNP is the goal. What features does one have the other doesn't reference the CCNA/NP?
Yes, you can get away with a 2950-SI. A 2950-EI is better. To do absolutely everything mentioned in BCMSN, you need a pair of 3550-EMIs, which is $5k+ out of your pocket.
I used a stock 2950-24 SI for my BCMSN, and it did most of what I needed. I also had a Cisco 2611XM with two FE ports which I put into bridging mode which allowed me to do most of the spanning tree stuff, including moving the root-bridge around, and most of the trunking stuff.
If you have the cash, buy the best you can afford, but you will get to a point of diminishing returns. Personally, I'd pick up a pair of
2950s, including 0,1 or 2 EIs depending on your budget, and if you need hands-on for the L3 stuff, look at an online rental lab.
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