Reflections on Cisco ENARSI Study

One LAB to rule them all

While studying for my Cisco Certified Network Processional Enterprise Advance Routing (ENARSI) specialisation, I eventually figured out a strategy to help me focus on learning and less on constantly creating LABs.

I decided to build a reusable (flexible) lab by simply specifying the L2 VLAN at the router with a sub-interface so that I could potential attach any router to any other router in a P2MP broadcast setup.

It is impractical for a production network as each router shares the bandwidth of a single link for all VLANs on the trunk, but it does provide a very simple, elegant and flexible solution in its design allowing for focusing on less lab building and more hands on in a variety of scenarios.

Interestingly, both IOSvL2 switches refuse to provision certain VLAN ranges in the device config I built, but that's probably a bug with either CML or the image itself.

EXAM

So the exam to date is nothing short of frustrating. Just when I think I've nailed a lot of the concepts in EIGRP, OSPF, redistribution and many other L3 topics and begin feeling more confident, I find that the exams pool of questions are completely disjointed. For example, in my last exam - just before the time of writing this - I had less than 50% of actual advanced routing questions and more around services, device access and extremely low-level and corner-case things like really nuanced MPLS. It's not helping me to overcome imposter syndrome and to me makes it feel like I'm just part of Cisco's additional revenue stream and business strategy rather than learning and valuable certification process.

It also frustrates me that I seem to have to retain and recall an insane and almost inhuman amount of low-level information on EVERYTHING no mater how relevant or related to advanced routing it may seem.

I may just pivot across to other vendors and technology because it seems as though my brain is incompatible with rote learning.