Thursday, September 3, 2009

How to build a Cisco CCNA Home Lab

By Bob Marshall

Many people ask me what would make a good CCNA lab? Well, that can be a tricky question based upon your budget and future Cisco aspirations. So lets start off with a few basic concepts I hope we can all agree on. Real Routers

You need a physical router as the simulators just dont have the ability to give you the hands on you need to see what happens when you disconnect a cable, put a cable in the wrong location or just plain configure the interface incorrectly. Dependant on what you do by mistake, you may see either the interface or protocol go down and based upon that it should give you a clue of where to start troubleshooting(hint, what layer is the interface at and what layer is the protocol at?). Anyway, you will come to find quite quickly that mistakes you make on Router 1 are affecting Router 4 all because you did not screw in a cable properly. No simulator can simulate that, so a router is invaluable.

I also get occasionally asked if someone can use their D-Link router or such in their lab. That class of home router generally does not support protocols such as RIP, OSPF, IGRP, etc. nor do they support the Cisco IOS which is a majority of the CCNA exam. So the answer is they are not really applicable to building your Cisco CCNA lab.

How Many Cisco Routers Do I Need?

Two routers really are required to see if anything works. If you have a very limited budget, you can receive value from only purchasing a single router over working with a simulator. However, you will not be able to see the main thing we are trying to accomplish. The propagation of route tables and the routing of data! The only way you can see if your configurations work, is to have at least two routers. That said, if you can afford a kit with more than two routers, it will enable you to exercise more complex scenarios. Therefore, I strongly recommend that you purchase a dual router kit or better that comes with all the accessories you need. Otherwise you can spend days or weeks trying to find all the little extra pieces you need to get your lab up and running. I mention this as some other resellers are selling their kits with 2500 routers and they are not including transceivers. Well how will you use the Ethernet AUI ports without them?? So this is basically how I view it. One router will give you the ability to run the commands on it and allow you to memorize the correct syntax and context in which to run the commands. Two routers will allow you to be able to see route table information propagate, data propagation and path election. In addition, you will see basic device elections. With three or more routers you will get all of the above and full device elections. Hopefully these tips will help you pick the right CCNA lab kit for you budget.

Can We Build A Lab That Will Cover Every Single CCNA Exam Concept?

We get this question quite often. Yes, we can, but it is not realistic for most customers who are self studying as this will cost well in excess of $5,000. If you have that sort of budget available, we suggest you pick on of the CCNP kits as that will get you through your CCNA exam and well on your way to your CCNP certification.

How Many Cisco Routers & Cisco Switches Do I Need To Complete Your CCNA Lab Workbook?

Our CCNA Lab Workbook was designed with the knowledge that most of our customers cant afford a large lab. Keep in mind, that you will see a variety of labs that were written for three of four routers below. That does not mean you cant complete most of them. It just for the most part means they will not be as complex as they could be.

Number of labs requiring only one router " 7

Number of labs requiring two routers " 11

Number of labs requiring three routers " 19

Number of labs requiring four routers " 4

Number of labs requiring one or more switches - 8 What Are Some Things I Need To Consider For My CCNA Lab?

Two new topics have popped up for the new Cisco CCNA 640-802 exam. They are IPv6(IP Version 6) and SDM(Security Device Manager) which is a GUI based way to configure your routers and switches. A common question is can the Cisco 2500 series routers support IPv6? Yes, they can if they are maxed out with 16MB of DRAM and Flash. Here are some more specs on Cisco routers and required DRAM and Flash to support IPv6 assuming you have the correct IOS.

As mentioned before, SDM is Ciscos Security Device Manager and is the GUI option to configure your routers. It is not supported on some of the older models. But the good news from a lab perspective is that you do not need it on every router to get a good grasp on how SDM works. The Cisco 3640 router is going to be the cheapest way to get SDM with a 10mb Ethernet interface and the Cisco 2600XM series seems to be the cheapest way to get SDM with a 100mb Ethernet interface.

Finally, I also have an IOS version column. As you can see above, the Cisco 2500, 2600 and 3620 models only support 12.3 whereas the Cisco 2600XM and 3640 units support 12.4. So if you want to have exposure the latest IOS that is running on routers in the real world, right now that is 12.4. But if your budget does not allow for it, you will still find value in the routers that are running the older 12.3 IOS.

Why Do You Sell Routers With Memory That Cant Run IPv6?

Not everyone has the budget to support every feature. So you will see that we still offer Cisco 2500 router kits with 8MB of DRAM and 8MB of Flash as being able to practice on routers that support 85% of the concepts is better than nothing at all if you budget is tight. Anything Else You Can Suggest?

Well, a few things. The Cisco 2500s are serviceable routers for your CCNA studies still as long as you have the proper IOS and maxed out memory with all the accessories you need. You might say, but they are only 10mb routers. True, but they still work. The major drawback besides the aforementioned lack of SDM and 12.4 support is that with 10mb routers you cant do your inter-vlan routing labs with them(which is true of any of the 10mb routers). So just make sure you have at least one 100mb router in your lab so you can do inter-vlan routing and that takes care of that issue and helps to keep the cost of your lab down for those with a tight budget!

You want to make sure your router can support IPv6 as doing those labs will really help the IPv6 concepts sink in. Finally, SDM is more than likely the wave of the future, so you might as well start to get used to it now! Do I Need A Switch?

This can be debated a few different ways. First some people will say that 80% of the test is based on routing. To which I will agree. But with only a small margin of error between passing and failing, not fully understanding switching concepts such as VLANs, STP, and root elections could be the one question that stands between you passing and failing your exam. There will be some switch questions which are memorization based such as What is a Layer 2 protocol used to maintain a loop-free network? Thank goodness we memorized STP. That said, it would be nice for us to be able to actually see the switching concepts work. So this is basically how I view it. One switch will give you the ability to run the commands on the switch and allow you to memorize the correct syntax and context in which to run the commands. It will also allow you to do some of the VLAN labs. Two switches will allow you to see VTP Domain & VLAN information propagate. In addition, you will see basic device elections. With three or more switches you will get all of the above and full device elections. Remember, we are only at the CCNA level right now so we will not need a Layer 3 switch like a 3550 just yet. But it is a cool concept of your CCNP studies. Finally you may ask why do some of my dual router kits not have switches in them. Well because you can quite simply go to the section on our site labeled Switches and add the switch you would like to be a part of your kit. The switches don't need extra transceivers, ports and such so I don't really have to kit them up with the routers. We do have some of the larger kits that have both routers and switches in them too. What Switch Should I Get?

This is one that there is so much debate on these days. I will give you my thoughts on it and there are a hundred different ways you can build a lab. I will give you the information and let you decide how you want to build your lab.

The Cisco 2950 switch is the switch that is covered on the test and has the exact IOS command set that you will see on the lab. So if you can afford one, it is great to get. But sometimes when customers only have a $200 budget, I cant suggest for them to get a switch and forego the routers. After all, the test is 80% routing! Back to the Cisco 2950, this is the best switch for the test if you can afford it.

But lets say you cant afford that switch , but still want a switch, what is next? We have the Cisco 2900 series. This is a step down from the Cisco 2950 and supports all the same CCNA test commands except the switchport and global vlan command. So with that knowledge, this switch may just work for you.

Finally, there is the Cisco 1900 series switches. There is not a lot of demand for these so they can be purchased very cheap. Some people say they have absolutely no value in a CCNA lab. I tend to disagree for the most part. You may ask me, hey, what are you smoking? The IOS that the Cisco 1900 series switches support is not the IOS that is on the test so how can it be useful? Well, lets go into knowing that they IOS commands on the 1900 series are not the ones that are on the test. Ok, so we are not going to focus on them(remember, there are only a very few switch IOS commands on the CCNA exam in regard to syntax), but concepts that I find many people having a hard time understanding in how STP works, how the device elections are handled and such. Those concepts work exactly the same way on a 1900 as they do on the 2950 switch. Not to mention that you can do your VLAN, VTP and other similar labs on the switch to get an understanding on how they work. So hopefully you can see why I still carry them to help customers who are on a tight budget get exposure to such concepts. *Note, as of January 2009 the prices have come down on the 2900 series switches to the point it does not seem to be of great value for us to still carry the 1900 switches. The price between the two switch types is so close it is better to spend the extra few dollars and get a 2900 series switch.

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