JNCIE-ENT – My Study Adventure

In this post I will discuss the process I used in studying for and passing the JNCIE-ENT Lab Exam. My hope is that other aspiring JNCIE candidates will find this useful information or perhaps even to push them to go for it.

Why did I decide to go for the JNCIE-ENT Certification?

For starters, I achieved CCIE status (Routing & Switching – #6105) in August 2000. I really hadn’t done a hand-on lab certification since that time, and I felt that the JNCIE would be a fun challenge to both sharpen my skills and to see the same technology from a different perspective. Given the march of technology over time, the JNCIE-ENT had much more focus on Multicast and IPv6 than the CCIE did way back then. I have been actively participating in several Juniper design and implementation projects over the past few years, so the timing was good for going for the JNCIE since I had a good base to work from.

I also just figured this was a good test of my grit in general. It’s good every now and then to push through and commit to something difficult no matter the circumstances. Given the difficulty of the JNCIE-ENT exam and my heavy consulting workload at the time, it proved to be a very good test of my mettle.

How did I prepare for the Written Exams?

The JNCIA / JNCIS certification materials are straightforward – the study guides included in the Juniper Fast Track Program are the way to go there. Discounted vouchers are available for the JNCIA / JNCIS exams – you may also want to try asking your Juniper account team for fully discounted vouchers.

When it came to the JNCIP, I found the recommended Juniper training materials to be the most helpful (AJER – Advanced Junos Enterprise Routing and AJEX – Advanced Junos Enterprise Switch). I did not actually take the classes due to time/budgeting constraints. However I did manage to get my hands on the courseware manuals.

I also had purchased the following books which were great for general knowledge although slightly less focused on the exam (not a bad thing):

Lastly, getting some hands on JUNOS is a very good idea for passing the JNCIA/JNCIS/JNCIP-ENT exams. An SRX100 is a good place to start if you don’t have some Juniper gear readily available, or you could possibly go with the Juniper Firefly Perimeter (formerly named the vSRX) – keep in mind that Firefly cannot do Ethernet Switching.

How did I get started studying for the Lab Exam?

After passing the JNCIP-ENT exam (March 2013), I took short break (about a month) to decide if I really wanted to go for the JNCIE. I knew that the time commitment would be substantial. I also knew that I’d be giving up quite a bit of nice summer weather for studying. In the end, I decided that I needed to go for it now or not at all because the timing was right – I had a few projects that had just wrapped up and I had just enough of a lull that I could really get going. So, with that, I committed to doing to taking the test and there would be no looking back.

My first definitive action was to schedule the Lab exam.  I scheduled the first test for August 12, 2013, which was about 3 months out, which I believed was enough time to really get sufficient hand-on practice with the stated exam objectives. There is something magical about putting an event on a calendar that forces your mind to start to figure out how to get it done. I did end up sticking with that original test date for my first attempt.

Secondly, I went out and purchased the iNET ZERO JNCIE-ENT study guide along with 10 lab sessions and started scheduling them immediately (once per week at first). I later purchased an additional 10 sessions before taking my first lab attempt.

After thinking about it carefully, I decided not to take the JNCIE Bootcamp. Given my consulting project workload and budget, I figured that it would be more cost-effective to take the exam itself once (or perhaps even twice) and still be less expensive. To get the most out of the bootcamp, you really need to dedicate an entire business week with no distractions, and that was just going to be extremely difficult for me to do at the time. I also was purchasing this with my own funds, so I figured $3,500 for the bootcamp (plus travel costs) was a bit much compared to $1,400 for each lab exam.

Lastly, I purchased the Proteus JNCIE-ENT Workbook as soon as it became available in late May 2013. I figured using multiple study guides was the best approach and this ultimately proved itself to be true.

I did refer back to the Junos Enterprise Routing/Switching books, but I do not think that those books are focused enough on configuration tasks to be a primary resource for preparing for the lab exam.

What did my practice lab look like?

As I had mentioned in my previous post, I did not seek to build out my own hardware lab, both for time and monetary reasons. When I did need access to the actual hardware (Especially to test out ethernet-switching functions such as Spanning-Tree and QinQ), I used iNET ZERO’s online labs.

I did use some of my own gear. I have an SRX100 and EX2200-C in my network which were very useful in testing configurations. You can do ALOT of with an SRX100 using virtual routers and logical tunnel interfaces. There are many blog posts that discuss this, including this one.

In addition, I also made extensive use of the vSRX (Firefly Perimeter) to build out a Multicast lab using 4 routers that closely matched the labs in the Proteus workbook.

What was my JNCIE-ENT study process?

Lab Attempt #1 Preparation – June 15 to August 12, 2013

For the first couple of months, I scheduled a weekly 8-hour lab session using the iNET ZERO lab and worked through the exercises in that book. When I got to one month before the exam, I started moving to 2 sessions per week, and then scheduled a session every day for the week before the exam. In total, I used 15 iNET ZERO lab sessions before my first lab exam attempt.

During this time, I also was reading through the Proteus workbook when I wasn’t doing the iNET ZERO labs. Where it made sense, I also utilized my practice lab to test configurations from the Proteus workbook.

I used Evernote to document my own “flash cards” for memorizing specific configurations or any other details that I needed to have “at the tip of my fingertips” for the exam. In the final 24 hours prior to the exam, I found myself focused more on my flash cards than the hands on configuration.

Lab Attempt #2 Preparation – August 27 to September 26, 2013

After finally getting word that I had failed (the wait period seemed like an eternity – almost 3 weeks), I immediately scheduled another exam and made my travel arrangements. As it worked out, I had another 4 weeks to study.

This time around, I did a detailed review of the Proteus notebook, did a few more lab sessions with iNET ZERO to specifically test out some specific scenarios where I had some issues during the exam (QinQ comes to mind – you specifically need EX switches in order to practice). I also continued my own hands-on configuration using the vSRX and SRX100.

Coming out of the 2nd lab attempt, I was somewhat confident that I had passed it, though I knew that I had missed some things.

Lab Attempt #3 Preparation – October 4 to November 15, 2013

After getting word on failing my second attempt – I have to admit I was a little unnerved. I went so far as to discuss the results with the proctor to make sure a re-grading attempt wasn’t necessary (you can order these for $250). In the end, the proctor did make me feel a bit better (while providing very little information) by at least indicating that he saw clear deficiencies in the 2nd attempt and also indicating that I did much better than the first attempt. At least I was getting somewhere.

With that, I scheduled the 3rd attempt immediately. Once again, I had about 4 weeks to prepare. Unfortunately, I had a major intensive project going on at this time. In fact, I really didn’t get much studying done until the 4 days before the exam. Fortunately, I was able to have complete focus over those 4 days which probably made up for several weeks of part-time study.

This time around, I decided to focus my lab work on my weakest subject (multicast)  while reading through the JNCIE-ENT Bootcamp courseware from someone else who had taken the class in 2013 (Thanks Victor!). The Bootcamp courseware was excellent in filling in the gaps from the previous workbooks.

Any tips for taking the lab exam itself?

I probably don’t have a lot of useful comments on this beyond what others have said on other forums, blog posts, and in the Study Guides noted in my previous post, but here are my top recommendations:

  • Don’t feel obligated to complete the test in the exact order as given – You must receive some points in each section in order to pass the exam, so you might as well go through each section and complete an item or two before moving on to the more complex items that are going to take more time to work through. On my third attempt, I specifically made a point of getting some of the basic infrastructure setup as requested (Spanning-Tree, OSPF, BGP sessions, etc.), and then jumped to the back to configure Multicast, Class of Service, and Systems services before jumping into the BGP policies, which I knew were going to take an extensive amount of time (I think I spent 90 minutes or so configuring those policies). Ultimately, this simply comes down to time management which is always a concern on lab exams.
  • Get at least 3 or 4 days (better yet a couple of weeks) before the lab exam to maintain a near 100% focus – For me, this was much easier said than done, but looking back, it was a big part of my improvement between my second and third lab attempts. I had a major project complete just 4 days before my third lab attempt and had the opportunity to completely block out my calendar (a rare gift).
  • Make sure to record the proctor’s contact information if provided – This ended up being helpful for me between my second and third attempts on the exam, if for nothing else, to get some confirmation that there was some thought process behind the lab results.
  • Don’t panic if you run into non-test-related technical issues during the exam – On my first attempt, the provided lab terminal dropped my sessions a few times early in the test (losing my work each time). On my second attempt, it took an extra hour for the proctor to print out my exam due to technical issues. In both cases the proctor extended my test time by the amount I was held up so I think the situation was handled appropriately, though in the case of the second attempt it did make for a very long day (I left the site just before 7 PM).
  • Get to know SecureCRT running on Windows – especially if you are a Mac user – since the lab machines are running Windows – I’d recommend just using SecureCRT for all of your lab practice if possible. Know how to use the available shortcuts using the default keyboard mappings in SecureCRT (especially Esc-Backspace, Ctrl-A, Ctrl-E, Esc-B, Esc-F), as well as how to enable the Anti-idle so that your sessions don’t timeout.
  • After each lab attempt – take detailed notes of what you may need to review immediately afterwards – In the event that you don’t pass, these notes will help you focus your study plan for your next attempt. I found it easy enough to do while sitting on the plane on my trip back from Sunnyvale (I took the test there on all 3 attempts).
  • Schedule a massage for the day after the test – OK…this is a little tongue-in-cheek, but boy, my shoulders really, really hurt after sitting hunched over a terminal for 9+ hours. In fact, I wouldn’t mind seeing Juniper incorporate better ergonomics into the JNCIE lab exam. Heck, perhaps they could even incorporate standing desks or *gasp* treadmill desks! I know I’d work better in that mode. Nevertheless, make sure you take a few breaks and stretch out.


I hope you find the notes above useful and perhaps even inspiring. If you have any additional questions/comments, feel free to add a comment below.


  • Victor


    thanks for sharing your experience. I have one question – is there is any “hints” to run multicast on the Firefly? I’m using 12.1X46-D10.2 version, but unable to see multicast source with “show pim source” command. Multicast traffic hits the interface (i see Input Rate). Firefly runs in the packet mode. Thanks

    • http://www.knill.net/ David Knill

      The version I was using was pre-release (early 2013 – 12.1I20130322_2104_slt-builder) – so it’s likely the version you are using is more stable. Outside of that, I don’t think I did anything too interesting – one thing worth noting is that I used “LAN Segments” inside VMware Workstation v9 when connecting the vSRX machines and VMnets when connecting the vSRX to the Windows/Ubuntu hosts (which were also virtual). Once I confirmed IP connectivity between the vSRX and the host, using iPerf worked well enough for test multicast streams.

      Sample Configs below. Notice that I configured a fairly low rate (10k) on the multicast senders/clients – I did get flaky results if I tried to transmit at higher rates:

      # IPv4 Server – Receiver
      iperf -s -u -B -i 10

      # IPv6 Server – Receiver
      iperf -s -u -B FF1E::1 -p 5002 -V

      # IPv4 Client – Sender
      iperf -c -u -i 10 -t 600 -T 32 -b 10k

      # IPv6 Client – Sender
      iperf -c FF1E::1 -u -i 10 -t 600 -T 32 -V -p 5002 -b 10k

      Hope this helps – David