Many people ask us what would make a good CCENT or CCNA R&S 200-120 lab? In this article will cover how to build an effective CCNA lab. Because there is so much to cover, we have broken it up into two sections. Part I will discuss how many routers and switches we need and why along with some other related topics. Part II will cover the features of individual routers, switches and modules along with IOS and memory requirements. Please do not skip any of this information as it is all very important for you to understand so you get the most value for your money in purchasing your kit. It is well worth spending 15 minutes reading these articles not to make a $500 mistake! So let's start off with a basic concept I hope we can all agree on. Real Routers & Switches are required for your CCNA Routing & Switching Lab!
You need a physical router as the simulators just don't 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. Dependent 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 real routers and switches are invaluable. We really suggest you read through this entire article from top to bottom to understand how to build a proper lab for your CCENT & CCNA studies.
Don't want to read the entire article? Watch it here. But there is more detail in the article than we could put in the video.
How to Build a CCNA Lab
What Are Some Things I Need To Consider For My Cisco CCNA Lab?
First is Cisco made the CCNA 200-120 exam quite a bit harder than the CCNA 640-802 exam. Cisco wants to make sure you really know your stuff on this exam. Basically they moved about 80% of the old CCNA 640-802 exam topics into the new ICND1 100-101 exam. Then they dropped a few concepts such as wireless and voice as they now have the CCNA Wireless and CCNA Voice specific exams and added a lot more troubleshooting to the CCNA Routing & Switching 200-120 exam. So what does that mean to you? The days of having a high level understanding of what is happening and passing the exam are gone. You need to practice on more complex setups and really understand what is happening. That is why when we revised our lab workbook we made it much more complex and explained the concepts in detail as you do each lab.
How Many Routers Do I Need for my Cisco CCNA Lab?
Two routers are the bare minimum 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 really work is to have at least two routers. Therefore, I strongly recommend that you purchase at least a dual router kit. But if you want the best experience, you will want to go with a three router kit. So let's review this in a little more detail of what each scenario will provide to you.
One router will give you the ability to run the commands on it and will 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.
Three or more routers and you will get all of the above, more complex topologies and full device elections.
Ok, so we say we suggest three routers and you see what we wrote above, but it just is not clicking why you need three routers as maybe you heard somewhere else two routers is all you need. Well let's go into a little more depth and take a look at the slide below.
In this slide from our study guide, you see a topology with three routers. Let's say we need to ensure R2 is your DR (designated router). If we just have two routers, we can simply set the priority of R1 to zero which will make that router ineligible to be a DR. So then R2 would be the DR by default. But if we add a third router, then we don't know if the DR will be R2 or R3. More than likely most companies you will work at will have more than two routers, right? So now you can see that we are going to have to do multiple configurations to influence which router is the DR in the more complex topology. So in this scenario, we need to increase the priority of R2 and leave R3 at its default priority to accomplish our goal. So hopefully now you can start to see why three routers are critical to really hammering home some of the CCNA concepts. So let's review another scenario below of why you need three routers in your CCENT/CCNA lab.
You will see that the lab topology(this is from our lab workbook) on the top has two load balanced WAN links (the two lighting bolts), a subnet off of R1 and R3 where the computers are and from R2 we have multiple paths to get to any of the subnets at the top portion of the topology. Now compare that to the simple two router lab below it. No load balancing, no multiple paths, no ability to set different costs on the links and obviously not as complex route tables.
So a quick scenario. Let's say one of the WAN links was configured super fast and the other one was a super slow WAN link. You are at the computer off of R3 and you are communicating with a server off of R1. The super fast WAN link goes down. What will your path be to the server off R1? Will the data travel across two routers traversing a super slow WAN link or traverse 3 routers utilizing fast links? Good question, huh? Now which lab topology do you think will give you a better learning experience?
Do I Need A Switch & If So, How Many?
If you would have asked me this question 5 year ago I would have replied the exam is 80% routing and you can memorize the little bit of switching that is on the exam. But with the recent 200-120 changes, inter-vlan routing is hit very heavy on the exam in various scenario questions. So if you can afford it, yes, switches are required. 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 similar to our router review, this is what you will get with the corresponding number of switches.
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.
Three or more switches you will get all of the above and full device elections.
Again, you may have heard that you only need two switches in your CCNA lab. Yes, you can get by. But you want to know this information inside and out. So three switches will give you the best learning experience. Let me prove it again.
Wow, there is a lot of information on this slide. Spanning Tree Protocol is used to eliminate loops in our network as loops are bad. So how can we determine which switch will be the Root Bridge? In general, it is based on the MAC address of the devices but it can be influenced by changing the priority on one or all of the devices. When a Root Bridge is elected, it is as if everything in the world will revolve around the Root Bridge. That dictates then which ports on the other switches are root ports, designated ports and non-designated ports. If also then impacts the states of the ports. So if the Root Bridge changes from Switch C to Switch B, then each port will change to a different type of port and state. Now we will have to figure everything out again from scratch. You might not fully understand this now, but by practicing with three switches in a complex topology such as this CCNA lab, you definitely will have a much deeper understanding of the technology at hand. Hopefully this example has fully convinced you of the value of a CCNA lab with three switches.
Sill not convinced you should have three switches in your CCNA lab? Well then maybe my final point will sway you. The topology in the diagram below is similar to what appeared on a previous version of the CCNA exam. So if Cisco can use multiple switches in the lab questions on the exam, don't you want to practice on scenarios similar to what you might see on your CCNA exam?
Sample CCNA Exam Scenario
How Many Cisco Routers & Cisco Switches Do I Need To Complete Your CCNA R&S 200-120 Lab Workbook?
Our CCNA Lab Workbook has been recently updated for the new CCNA exam and was designed with the knowledge that most of our customers can't afford a large lab. We wrote our Lab Workbook v2.0 to the specification of three routers and three switches. In a perfect world you will have three 1841 routers, three WIC-2T modules, a 3560, 3550 and 2960 plus the associated cables. Does that mean that you can't complete the labs if you only have two routers or two switches in your lab? No, it just means for the most part those labs will not be as complex as they could be and you won't see any many routes propagate. But you still should fully understand the concept which is being presented.
Now you can review the above link for our Lab Workbook v2.0 R&S 200-120 to see all the topics covered. A physical copy of the Lab Workbook is included with our dual router or better kits. Note in the topology diagram below how complex we make our labs. These are not straight forward two link setups. We include redundancy, multiple subnets and explain it all in great detail. There is no other CCNA book out there anything close to what we have created! Accordingly we are the premier CCNA lab supplier with support second to none! Click on the topology picture to see a PDF of the sample lab. This is why we really suggest three of the 1841 routers in your lab as we use every single interface and hit heavy on advanced OSPF, advanced EIGRP, EtherChannels, Load Balancing, etc.
How Do I Know What Routers & Switches I Need In My CCNA Lab?
In part II of our article we are going to cover the different routers, switches, modules, cables, memory requirements, IOS versions and many other things you should think about when buying your CCNA lab kit. So click the link below to continue!
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