If you have been following these articles for the past couple weeks, you know
that I am in the middle of a series of articles that are attempting to provide some new ideas on how to obtain your Juniper JNCIS-ENT certification. Here, you can link to Part 1 (What is your plan?) or Part 2 (Expert-led resources).
As I am halfway through the series, I decided to review what we have talked about so far. Up to this this point, I have written about many of the suggestions or ideas I have gathered as I talk to others about how they passed their vendor’s exams. Moving forward, the suggestions and recommendations I make will start becoming more specific or situational to Juniper and the JNCIS-ENT.
So what written materials are available to help you obtain your JNCIS-ENT? If you are like me, this was the first question you asked when you decided to obtain this certification. So where do we go to gather data and begin researching how to tackle a new problem—Google of course!
Two bad things will happen if you start here and plan your study based on the data you find. The very first link you see (at least as of this writing in mid-January 2014) is a link to a Juniper eBook PDF that was first printed in 2004 (updated in 2006). Then, you will find links to a host of different practice exam from vendors of varying degrees of reliability. So let’s start this discussion by implementing the first rule of gathering research data using Google—validate and verify. In other words, validate the content’s authenticity and verify its accuracy. Following this rule takes time—so many of us don’t do it. In this case, if you skip the authenticity and accuracy check, you will experience the pain of not being prepared for this exam! Let me explain…
Let’s start with the very first link in your google search—The JNCIS Study Guide eBook PDF. At first glance, this seems very legit. In fact, it was written and published by Juniper Networks. However, it was first written in 2004 (updated in 2006). The JNCIS program has gone through some changes since this book was written and, as you would expect, technology has changed a bit since the first iPhone was released.* This book also has material in it that you simply do not need for the JNCIS-ENT (two chapters on MPLS). Having said all this, the book can play a role in your exam prep—as a backup or background guide to understanding general technology concepts. For example, they have a chapter on OSPF that is probably still quite relevant (except for any OSPF v3 information) in understanding how the protocol works at a high to medium detail level.
The second set of links point to practice exams from various sources. Here, you really have to be careful with some very questionable material and sources. Of course you have the normal concerns about whether the answers to the questions are correct. In addition to that concern, some of these links are advertising that they have actual test questions from the JNCIS in their exam. This seduction is very attractive for many reasons. However, just trust that if you can access these materials—so can the Juniper certification gods. If you use these ‘practice exams’ to prepare for the real thing, do not expect to memorize answers and see the same questions on the exam. Moreover, expect the exam to ask questions that are just similar enough that you will get tripped up (or confused) at least and caught as an actual cheater at worse! These and all practice tests can play a role in your exam prep—but only if you do the hard work of studying and understanding the materials first.
Ok, I hope I have convinced you that there is no value to travelling the easy road. So what resources are available? Well, for this exam, the answer is actually pretty easy—Juniper provides about 90-95% of what you need to pass through their Fast Track program. Again—if you hav
en’t already—go right now and sign-up for the Juniper Network Fast Track Certification program. At this site you’ll find study guides for the JNCIA and the three primary JNCIS tracks (ENT, SEC and SP). Download the JNCIS-ENT Routing Study Guide and the JNCIS-ENT Switching Study Guide and you are set! This material closely matches the material you find if you pay to take the exams. In addition, the vast majority of the configuration scenarios and JunOS commands you will be tested on are available in these study guides. There are a couple of very specific scenarios related to high-availably configuration that will require access to hardware or the Juniper JEX and JIR lab guides to understand and review. However, if this is your only written resource and spend the time to understand the concepts you need understand and memorize the facts you need to remember, you should do well on this exam (assuming you also have access to hardware or lab time).
One note: If you were able to attend JIR or JEX, your classroom textbooks contain are very similar content to the study guides mentioned above.
So how do you know if you are prepared? Well, when you begin to recognize some problem images in the study guide—you definitely are getting close. I am not talking about missing words or typographical errors. I am talking about conceptual issues in some of the diagrams. These aren’t glaring errors—and in fact you could even argue that the images are correct for the purposes of the specific topic being discussed and the audience it’s intended to help.
For example, in the BGP section, there is a diagram to help you understand how BGP advertises its routes to neighbors on page 4-18 (also seen below). One of the purposes of this diagram is to point out that BGP does not (by default) change the next-hop attribute when advertising routes between IBGP peers. If this is true, then how do downstream routers know the correct next-hop to access a particular network? (Study Juniper’s BGP implementation to find the answer!) The graphic indicates that R1 and R2 are IBGP neighbors, when in fact they are not. R1 is EBGP, since it is talking to an
other autonomous system and R2 is IBGP since it is only talk to other routers in the same AS. For the purpose of understanding the next-hop concept, this diagram is perfect. However, in the larger context of how BGP works, this diagram has problems. R1 has a dual nature—one interface is EBGP the other is IBGP. But the study guide doesn’t really explain this. There are several other images with similar type problems. Not glaring, but it could be more clear. Some of these problems are so subtle, you may never see them unless they are pointed out to you. This is where having access to a Juniper expert can be very helpful (see my previous post about gaining access to expert resources). As you begin to recognize these problems, you can gain confidence in that you understand the concepts and technology required for passing this exam.
This is a good time to talk some more about practice exams you find from questionable sources on the web. First: don’t trust them. If you need something to measure your learning progress, it’s fine to use these as a tool. However, understand that the quality of these tests is very questionable. These tests should only be used as a rough measure of how you are retaining the material. If you download one of these, the best use case is to treat the exams as a bank of questions that you need research and answer. In other words, throw out whatever answers they give you and find your own answers and explanations for each question based on the study guides or the Juniper technical knowledgebase. Once you have done this, you have a new study tool that you can use for last minute review. Wherever possible, grab the exact text from the Juniper source and use it as the answer. Anywhere that you are unsure or it is unclear, get your Juniper expert involved to help wade through what is being asked and what a correct response should look like.
Finding study and reference material specific to Juniper certification exams can be difficult. When you compare what is available on Amazon for exam prep between Cisco and Juniper you might begin to question your choice of attempting a Juniper certification path. 
This is not necessarily a bad thing. It means that you must have a strong understanding of the items the exam covers. However, how can you get this understanding unless you have access to reference material? Chicken or the Egg, eh? Well, you start by identifying exactly what is it you need to know. Do this by reviewing the detailed exam outline available at the Juniper Certification program site. Nobody wants to study material that will not be covered on the exam!
I think Juniper feels your pain on this issue,too. Juniper seems (to me, at least) to be aggressively growing its certification program. The Fast Track program is evidence of this—as is the JunOS Genius app they recently released for the JNCIA. It seems every week they are releasing additional short-form education videos they call ‘Learning Bytes’ to help fill-in this gap. They also publish and sell the Day-One books and a very low cost (just few bucks) if you download the Kindle version. The Juniper Day-One series help provide additional background on various popular subjects in the Juniper universe.
There are sever
al non-Juniper resources that might help fulfill some of your learning needs. If you are serious about technology and learning, I strongly encourage you to consider a Safari Books Online account. It costs between $10 and $45 per month, depending on features, but you get access to thousands of technology and business books from major publishers. Using Safari Books, you’ll see that O’Reilly has about 7 or 8 really good Juniper related books that can help fill-in the blanks on specific hardware lines (for example SRX devices or EX switches). Also, the Internet is full of YouTube videos that explain a wide array of technical concepts (BGP, OSPF, routing basic and much more). Be aware that many of these videos are taught from a Cisco hardware perspective. A video that describes how OSPF works is great until it starts spitting out the Cisco configuration commands for getting it running on your router.
Some final thoughts about written exam prep materials…first, always pay attention to the publication or creation dates. Anything older than a 2 or 3 years old should be relegated to background material and not a primary source for accurate information. If you do not have one already, develop a consistent method for categorizing and storing bookmarks and links to blogs and other online Juniper reference materials. Safari, IE and Firefox all have cloud-based syncing solutions so you can store your bookmarks in the cloud once and access them from any other PC you are logging into.
So what written exam prep materials are you using? My listing here was definitely not comprehensive. Help your fellow knowledge seekers out by posting your favorite resources in the comments.
*The first iPhone was actually released in 2007, but you get the idea…
Links:
Juniper Networks Fast Track Certification Program http://www.juniper.net/us/en/training/fasttrack/
Juniper Networks Certification Program – Enterprise Routing and Switching Specialist Certification http://www.juniper.net/us/en/training/certification/e_track.html#jncisent
Safari Books Online http://my.safaribooksonline.com
O’Reilly Publishing – Juniper Networks related books http://search.oreilly.com/?q=juniper&x=0&y=0
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