Home Lab Archive

Thursday, 21 September 2000 19:00 administrator

Set Up Your Home Router Lab! Part 1 - Archive

by Erik Westgard and Michelle Truman 

January 2000 
<webadmin - this is a very old article I found however the premise is still applicable for todays home lab. The reason I posted this was I was hoping this would give some insight into how to setup a serial to serial connection in a home lab. If you look it is fun to see that we can now purchase a 2600 router on eBay for about $20.00  - The article was published in January 2000 and at that time the cost was considerably higher than $20.00! >

To really learn routing and demonstrate the full power of IOS and the operation of routing protocols on a simulated wide area network (WAN), you'll need at least two routers connected together. Many production Cisco installations around the world use routers as the building blocks of their wide area networks. Common configurations such as a hub and spoke configuration include a headquarters and one or more branch offices, which is worthwhile to simulate on your lab. Most Cisco routers are equipped with one or more LAN ports and serial connections. Normally, the serial ports go to DSU/CSU (Data and Channel Service Units), which in turn connect service provider wan links.

 For the purposes of a home lab, you can connect serial interfaces with what is known as a "back to back cable assembly." You can connect Ethernet interfaces via a hub or crossover cable, but most of the available router models have only one Ethernet interface, and you don't get to work with serial interfaces, which you'll find in the exam requirements.

To connect serial interfaces, you need a DCE cable on one router and a DTE on another. The most common serial router cables are equipped with V.35 connectors -- female for DCE, and male for DTE. The routers themselves have one of two kinds of female jacks for serial interfaces -- a mini-DB60 on the new models and a larger, DB50 jack on the older models. Make certain you have the right types of cables and that you're careful with the pins on these cables, as they're delicate. (It's actually possible to connect the DB60 connectors upside down!) Most router cables aren't found in local computer stores, so you'll need to buy the official Cisco proprietary cables at around $100 each new. The used price is about half that.

 One important note on connecting routers via back-to-back cables: At least one router must support clocking (DCE) -- the IOS "clockrate" command. The 2500, 3104, and 4000 serial interfaces do, but some older 3000 and IGS models don't. Let's look at some of the new router models that can be used in a home certification lab:


Used Routers

Since you're looking at the need to support the full IOS protocol and feature range for the exams, one good choice is to pick up used enterprise-grade routers. Cisco hardware is rock-solid. So if you buy a unit that's working, the fact that a system isn't supported by Cisco any more should not be a major worry. (When Cisco says a router has reached "end of support," you can't buy a service contract or get factory-supplied support or parts any more.)

Some of these models aren't Y2K certified, although this has much to do with the IOS version you're running. Cisco routers have real time clocks, but these don't seem to be critical to the operation of the routers.

Watch for "Cisco Pro"/"White Box" models of many routers advertised. These were the result of a temporary experiment by Cisco in selling software feature-limited routers via resellers and dealers. This experiment has ended, and you can upgrade these routers in software and firmware to look like a normal router of the same model. Cisco Pro models sell for less in the used market.

Token ring models are available, and tend to be cheaper in the used market. The serial ports work the same; and you can find back-to-back cables, so you could connect servers to the token ring interface without an external MAU hub unit.

Tip: If you are planning to advance along the CCIE certification track, you'll want to have access to at least one token ring router. There you'll encounter emphasis on IBM protocols such as SNA and ring technologies such as Source route bridging and DLSW+.

The used market takes several forms. eBay.com and other auction sites bring together buyers and sellers. At any given moment, eBay usually has 400 or so Cisco listings, many labeled with "perfect for CCNA." (Be a bit careful when you buy this way that you truly know what you're getting.) Cisco resellers are another source -- some will work with home lab customers, though most seem to prefer high-volume commercial customers. You can also buy routers from ads in newsgroups, such as the ISP equipment list.

We've seen a demand for used Cisco routers pick up in the last year, due to certification testing needs and because of a Cisco trade-in program that's on-going. Series 3000s are desirable for labs, but rare in the used market; they can be worth a lot in trade on new Cisco routers.

Memory for upgrading routers is widely available. You can buy actual Cisco-boxed and branded upgrades for many models, but these can be costly. Dealers will sell "Cisco Approved" memory for less, and you can find various types of generic memory chips for even less, such as on the auction sites. Cisco allows the use of certain other brands of approved memory even under their service contracts. Each model has complicated memory-related upgrade rules, so read the CCO memory upgrade articles carefully. You usually need a bare minimum of 4M of RAM (used for buffers and table storage) and 4M of flash (used to store IOS for booting) to run a Y2K-compliant (and exam-friendly) 11.x level of IOS.

Tip: Remember that boot ROM upgrades for out of support older routers aren't available any more.


Used Models

Our advice? We'd get a 2501 (a Pro model if you want to save a little and aren't worried about resale) along with a SmartNet contract to get CCO access and the ROM and IOS software upgrades you may need. We'd bring it up to 8M of flash, and at least 6M of RAM. For your second router, another 2501 or a 4000 would be ideal, or, for those on a budget, a 3102. The cheapest possible lab would be a 3104/3102 or 3104/IGS combination, but you wouldn't be able to buy a software or hardware contract for these.

In Part Two, we'll cover setting up your lab.

Last Updated on Saturday, 22 October 2011 05:15