CCIE Exam: Enterprise Infrastructure

Period: 1st September to 30th September

Hours Studied: 93 hours

Total Hours Studied To Date: 498 hours

Study Resources:

  • CBT Nuggets: IPv4 Multicast Fundamentals [link, requires login]
  • Cisco Learning Network: Designing Cisco Enterprise Networks (ENSLD) v1.0 [link]
  • Cisco Press: CCNP Enterprise Design ENSLD 300-420 Official Cert Guide: Designing Cisco Enterprise Networks [link]
  • Cisco Press: Cisco Software-Defined Wide Area Networks: Designing, Deploying and Securing Your Next Generation WAN with Cisco SD-WAN [link]

Study Sprint: None

Previous Period Goals Status:

  1. Pass the Implementing Cisco SD-WAN Solutions (300-415) specialist certification exam
    I completed this exam on September 11th 2020 – I wrote about the preparation journey and experience in the article “Passing Implementing Cisco SD-WAN Solutions” [article link].
  2. Commence studying Multicast and reading more about QoS
    I kicked off studying multicast with Keith Barker’s CBT Nuggets IPv4 Multicast Fundamentals skill. It was a great introduction to the topic which was supplemented well by the CCNP Enterprise Design ENSLD OCG.
  3. Finish off the last remaining topics under exam domain “Transport Technologies and Solutions.”
    Did not make achieve this goal as I took two weeks off studying Cisco technologies after passing the Implementing Cisco SD-WAN Solution (300-415) exam.


Topics Studied: Cisco SD-WAN, Multicast

Cisco SD-WAN

I reviewed all topics on the exam blueprint before sitting the Implementing Cisco SD-WAN Solutions (300-415) specialist certification exam.


I broke into multicast topics at a high level by using Keith Barker’s CBT Nuggets IPv4 Multicast Fundamentals skill. I got hands-on with the technology by exploring how multicast is configured at one of the larger sites that I support.

  • 1.6.a Layer 2 multicast
    • 1.6.a i IGMPv2, IGMPv3
    • 1.6.a ii IGMP Snooping, PIM Snooping
  • 1.6.b Reverse path forwarding check
  • 1.6.c PIM
    • 1.6.c i Sparse Mode
    • 1.6.c ii Static RP, BSR, AutoRP
    • 1.6.c iii Group to RP Mapping
    • 1.6.c iv Bidirectional PIM
    • 1.6.c v Source-Specific Multicast
    • 1.6.c viii IPv4 Anycast RP using MSDP


Top 5 Weaknesses

  1. Route filtering with any routing protocol: No changes. Knowledge Rating: 3.5/5
  2. Redistribution between any pair of routing protocols: No changes – mainly need to grind out more labs. Knowledge Rating: 3.5/5 [+0.5]
  3. Multicast: I have developed a high-level understanding of multicast this month. I need to spend more time reading about how PIM, IGMP, dynamic RP discovery (Auto RP, BSR), MLD, and MSDP work. Once I “understand” the theory better, I’ll spend more time labbing concepts. Knowledge Rating: 2/5 [+2]
  4. MPLS: No changes. I enrolled in Micronics MPLS Zero-to-Hero class in September but may need to resit the class due to timezone and work scheduling clashes. Still feeling very confident with this topic. Knowledge Rating: 4.5/5
  5. QoS: No changes, scoped for mid-October. Knowledge Rating: 2/5


Top 3 Goals for Next Period:

  1. Pass the Designing Cisco Enterprise Networks (300-420) specialist certification exam
  2. Complete Multicast and QoS items on the blueprint
  3. Complete the Transport Technologies & Solutions domain on the blueprint by finishing off FlexVPN topics



The first half of September saw me pick up the momentum that I developed in August for Cisco SD-WAN topics, which saw me successfully pass the Implementing Cisco SD-WAN Solutions (300-415) specialist certification exam. Passing this exam was a significant milestone in my CCIE journey and boosted my confidence and morale significantly. It was an incredibly tricky but fair exam which required me to think through questions carefully throughout the full duration of the exam. The staff at the Pearson testing centre jokingly mentioned that they had never seen me, a regular candidate, use up all of my exam time. I felt like it was official – I had just put a significant dent in the “Software Defined Infrastructure” domain on the CCIE lab exam blueprint. I immediately celebrated my success by grabbing a big breakfast at one of my local cafes.

I was over studying anything related to computer networking after I passed the SD-WAN specialist exam, so I elected to take a two-week break from my CCIE lab studies. I switched gears in my brain and obtained the AWS Cloud Practitioner certification for work, which was an incredibly fun experience. During my downtime, I decided to catch up on some Netflix shows, played through “Super Mario 3D All-Stars” on the Nintendo Switch, caught up with my friends and family, and got back into my exercise routines. You must listen to your body and take moments to rest and recharge your brain throughout this journey.

In the last week of September, I spent most of my time developing a high-level understanding of the multicast topics on the blueprint. I cannot tell you why, but I felt like multicast was going to be some ugly beast that was going to be difficult to slay. I chatted with some colleagues about it and one of them, a gentleman by the name of Azeem, told me that if I thought of multicast as “routing away from yourself instead of routing towards a destination” that I would be fine. He was correct! I believe that with some extra reading and labbing that I will close this topic out in early October.

I  want to take a moment to share a “win” with you all that I have had during my CCIE journey – I got a promotion at work! Yay!!! I have taken up the mantle of “Specialist Network Engineer” at BHP’s Olympic Dam site in South Australia, which will see me working with two former colleagues of mine to improve the site’s IT and OT networks. It will be an excellent opportunity that I am incredibly grateful for and further motivates me to pass the CCIE Enterprise Infrastructure exam. I feel like studying for the CCIE helped me crush the technical interviews and is setting me up for success in this new role.


Key Takeaway

Rest is not idleness, and to lie sometimes on the grass under trees on a summer’s day, listening to the murmur of the water, or watching the clouds float across the sky, is by no means a waste of time.” – John Lubbock.


My Cisco SD-WAN Certification: 1 exam down to support my CCIE lab strategy, 3 to go!

SDWAN Certificate


From the Cafe: My post-SD-WAN victory breakfast – shakshuka bowl