CCIE Exam: Enterprise Infrastructure

Period: 1st May to 31st May 2020

Hours Studied: 50.0

Study Resources:

  • CBT Nuggets Community 1-on-1 Mentoring
  • Micronics Training – OSPF Online Class
  • RFCs (1583, 1587, 2328, 3101, 5185)

Topics Studied: DMVPN (single hub) & OSPF


  • 1.4.a Adjacencies
  • 1.4.b Network types, area types
  • 1.4.c Path Preference
  • 1.4.d.i Operations: General Operations
  • 1.4.e Optimization, convergence and scalability
  • 1.4.e.i Metrics
  • 1.4.e.ii LSA throttling, SPF tuning, fast hello
  • 1.4.e.iii LSA propagation control (area types)
  • 1.4.e.iv Stub router
  • 1.4.e.v Loop-free alternate
  • Prefix suppression


  • 3.2.a Troubleshoot DMVPN Phase 3 with dual-hub (partial progress, progressing to dual-hub next period)
  • 3.2.a.i NHRP

Top 5 Weaknesses:

  1. Route filtering with any routing protocol
  2. Redistribution between any pair of routing protocols
  3. Multicast
  4. MPLS
  5. QoS

Top 3 Goals for Next Period:

  1. Finish DevNet Associate to enable progression to DevNet Specialist ENAUTO exam
  2. Finish OSPF & DMVPN items & consolidate notes
  3. Start EIGRP & BGP Revision, commence MPLS studies


This first period has been a little clumsy as I figure out the rhythms and routines that I need to be adopting to develop consistency. I also had to switch topics to Azure Fundamentals (AZ-900) as my workplace is placing a large focus on how cloud technologies can be appropriately utilised to unlock value within the business.

On the bright side I am labbing again after installing CML2 on my laptop, but still need to post lab times on Router Gods for accountability. Time starvation resulting from poor management of my university studies has resulted in this, so I should not see this problem after final examinations end in mid-June.

Attending Micronics Training OSPF Online Class conducted by Narbik Kocharians has finally led me to understanding the LDSB, specifically Type 4 LSA which has always caused issues for me. Helping two CBT Nuggets learners with OSPF via the slack community has been amazing as a knowledge check as teaching forces me to articulate things simply while responding to questions on the fly.

I feel like I need to get a move on with my DevNet studies and develop a routines so that I am always labbing the Infrastructure Automation and Programmability topics. I think that forcing myself to dedicate 1 day per week to automate whatever I have covered (even if it’s just verification commands) will do the trick. Maybe I should hack together a social media bot that will ruin my life unless a GitHub commit periodically occurs…

I must develop revision materials (Anki Deck) urgently to help retain knowledge and also develop a good revision routine.

From the Whiteboard: Drawing the OSPF topology based off LSDB contents (from right to left)