Is there a single best switch model series to buy to build a CCNP lab in 2010? I think the clear winner for a CCNA lab would have to be the 2950 series switch, but the choice is not as clear for CCNP. Today I'll look at the main options and discuss the pros and cons. I'll start with a couple of background topics, and then compare 4 model series: 2950, 3550, 2960, and 2900XL.
(Sorry for the length of this post - I'm trying to get the series wrapped before I take off for some upcoming vacation.)
1) Switch IOS Considerations
Understanding switch software poses one of the bigger challenges when considering which used switches to buy. A given software version on one switch model series may not have the same features as the same version on another switch. While the equivalent does happen with routers in some cases, the danger appears much greater with switches. So, when researching switch IOS versions and feature sets, you can't just search the IOS version/feature set alone - you must do so in the context of each switch model series.
To give us some context for discussion and reference, I've picked a couple of IOS versions on which to focus for a CCNP comparison: 12.1EA and 12.2SE. Why? The latest version for 2950's is 12.1EA. At the same time, 12.2SE is supported on the 2960 and 3550 series, but not so new as to make me think that you wouldn't find many switches with this version on the used market. Click here to see the CCNP features versus these IOS versions on various switch models.
Finally, most of the EBay listing for switches do not mention that IOS version, at least in my experience. So, be ready to ask before you buy, and do a little searching around Cisco's feature navigator (www.cisco.com/go/fn) to validate what's supposed to be supported.
2) 2950 Series Background
Before diving into the CCNP discussion, we need to discuss a little background on 2950's. The 2950 series was popularly sold as new in the early to mid 2000's, but is now in End-of-Sale status. These models have been in a sweet spot of having relatively good and recent feature and command support, while being old enough to have a good price in the used market. Our pricing tests show these in the $75-$100 range over the previous month. The commands, and the show command output, tends to more closely match the syntax and output expected on the newer and still-sold-as-new 2960's, whereas the even older (but cheaper) 2900XLs have some command and output differences. In short, it's a good compromise of price versus function.
The IOS support picture for 2960's is frankly a bit fuzzy, and that fuzziness does matter to what you buy. Cisco originally offered two main 2950 options: standard models and enhanced models. The Enhanced models originally had more features. You had to pick standard or enhanced when you ordered the switch, and you could not later field upgrade the software to make it an enhanced switch.
However, it appears that over time, Cisco started supporting more and more of the enhanced features in the Standard 2950's. Over time, the Cisco feature navigator reflected these changes. Today, per the Cisco feature navigator, if you loaded the most recent IOS version and feature sets, some IOS names like "C2950 EI and SI..." are listed, implying one code build that would run on either an SI or EI switch. (The EI and SI refer to Enhanced Image and Standard Image, respectively.) There's more background on this page if you're interested. So, while differences do still exist between the Standard and Enhanced switches, the differences at later code versions is not a lot, and they may well be the same. It's just hard to tell from what documentation I've been able to find.
The choice of whether a 2950 is a Standard or Enhanced switch is based on the model, not based on the software installed. So, when buying, you have a choice: buy a Standard model or buy an Enhanced model. The prices do appear to be $40-ish different in our pricing survey on EBay. However, keep in mind that at later code levels, the Standard switches may well have all the features you need. So, like I said, it's a bit messy.
3) 2950 for CCNP
CCNP requires switching features for the SWITCH test of course, plus some for the TSHOOT exam. Using the list of CCNP switching features, compared to the various IOS versions and models, it looks like 2950's provide significant support for CCNP features. (Note: use these lists at your own risk, but I do try to keep them accurate. Please send notes about any errors to labdata at certskills.com to help me improve the listing.) If you buy a 2950 that supports 12.1EA code, assuming my list is accurate, then you'll get all the CCNP switching features supported, except:
- Private VLANs
- VLAN ACLs
- Dynamic ARP Inspection (DAI)
- IP Source Guard (IPSG)
- Layer 3 forwarding (with VLAN interfaces)
- Layer 3 Routing Protocols
- Layer 3 Default Gateway protocols (HSRP, VRRP, GLBP)
- IP SLA
The list may seem long, and may drive you to want to get a better switch. That's actually a reasonable response. However, there are reasons to think that most of these missing features are not a big deal:
The last three items in the list can all be configured on routers, and the configuration is substantively like what you would use on switches that support these features. You'll have routers anyway.
Layer 3 forwarding does not require a lot of configuration. Also, you can configure it with the switching module in 3640's, and on 877 model routers, so if you already have this router hardware, you may not need to get this function in your switches.
Price: at $70/$115 (standard/enhanced), the prices are somewhat reasonable for what you get, and noticeably cheaper than the 3550's.
CCNA: An Enhanced mode switch should cover everything for CCNA switching prep, at least that I can think of. So, it's a great model for CCNA's who plan to move on to CCNP.
But, is it the clear winner? Let's look at 3550's next.
3) 3550 for CCNP
The 3550 series has two main software branches to consider for CCNP Prep: SMI (Standard Multilayer Image) and EMI (Enhanced Multilayer Image). Like 2950's, Cisco sold these switches as either an SMI or EMI switch. However, unlike 2950's, you could buy the cheaper 3550 SMI switch and upgrade to EMI. So, in the used market, you'll see references to an "SMI switch with EMI software", which means that they just upgraded the software to EMI. (Note also that later 3550 IOS versions exist that replace the SMI and EMI names - namely, IP Base and IP Services.)
As for functional differences, both SMI and EMI support layer 3 forwarding and HSRP, but the EMI image is needed for the more advanced routing protocols, including BGP and OSPF. Other than these differences, the switches appear to be functionally identical for CCNP prep, at least from what I read. But there's a lot of nook and crannies to discover, so let me know if you've seen any differences.
Our price checks put these at $250/$290 for SMI/EMI. The biggest surprise was that these prices are higher than our April 2009 survey. While our survey methods are somewhat informal, it's a big enough difference to make me thing the prices actually went up a little.
Compared to the 2950 series, the 3550 bridges the gap to complete CCNP switching function support. 3550's support everything in the CCNP switching features list, with two small exceptions:
- VRRP
- GLBP
Of course, neither of these two features are a big deal if you have routers, because routers can support HSRP, VRRP, and GLBP. So, the 3550's give you more complete coverage of the CCNP switching topics.
4) 2960 for CCNP
Cisco still sells 2960's as new, but in my opinion, these will be the logical replacement for 2950s in the used market one day. (Do you have an opinion about others that might fit that role?) But I think that day is still too far off, for a couple of reasons.
First, our surveys show used prices in the $400's. You could literally get 4 enhanced 2950's for the same price as a single 2960 with LAN Base software (2960's have LAN Lite software, more akin to 2950 standard, and LAN Base, more akin to 2950 Enhanced).
Second, compared to used 3550's, you actually lose some CCNP features, namely:
- Layer 3 forwarding features
- IP SLA
- Private VLANs
In short, while I'm mentioning these for the sake of discussion and argument in the blog, I don't think these are reasonable options today. Do you agree?
5) 2900XL for CCNP
The 2900XL series, and its somewhat related cousin the 3500XL series, were the generation of access layer Cisco switches for the Enterprise prior to the 2950 series. These were mostly sold in the 2nd half of the 1990's. However, they run IOS, with the same general commands in use today.
Why consider them for CCNP? They're cheap. At $30 each per our survey, vs. a $70 standard 2950 or $115 Enhanced 2950, the 2900XLs are a compelling argument. Certainly as a 4th or 5th switch to have more Spanning Tree platforms, these switches make a lot of sense.
Using switches that were getting old 10 years ago has some downside, as you might expect. First off, I don't list 2900XLs in the CCNP comparison tables because I think they're so old that I don't trust the Cisco Feature Navigator support for them. That's not a slam on the Feature Navigator, by the way - the timing of when the Feature Navigator has widespread support of switches happened around the same time that these models were reaching End-of-Sale. If you look on the feature navigator today for 2900XLs, you can find one model for ATM, but not all. In short, I can't tell what features are supported without just buying a few and trying all the related commands, and I'm not going there. (Feel free to fill in any holes if you have some at home.) Also, some commands won't be supported, some config commands have slightly different syntax, and some show command output lists data in different places.
I wouldn't want to have to do most of my command practice on 2900XLs, but I might have a few in the lab just to have more Spanning Tree platforms to make the topology more interesting.
Earlier posts in this CCNP Lab series:2010 CCNP Lab Series Overview
Layer 3 Topologies for CCNP Prep
LAN Switch Topologies for the New CCNP
The Right Router IOS for your CCNP Lab
The Best Router for CCNP Prep in 2010
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