Contents
Why a Homelab?
After 8 years managing production networks, I still keep a personal lab running. Not because I need it for my job — my employer has Cisco CML deployed for production testing. I keep it for three reasons:
- Break things without consequences. A production network can't absorb experimentation. A lab can.
- Stay ahead of what I haven't deployed yet. IOS-XE features I haven't touched in production, NX-OS VXLAN/EVPN, Palo Alto PAN-OS features — the lab is where I get reps before they appear in a real change request.
- Certifications. Preparation for CCNP and above requires building and troubleshooting real topologies, not reading. There's no substitute for watching a BGP session come up after you configured it from scratch.
The Hardware
Lab Server — Intel NUC i7
I built my lab server around a 13th-gen Intel NUC Pro because:
- It fits on a shelf (no rack needed)
- 64 GB RAM is enough for 15–20 simultaneous lab nodes
- 2TB NVMe means fast boot times for every VM
- Low power draw — less than 35W at idle, around 60W under CML load
Alternatives I considered:
- Used Cisco UCS C220 (cheap, powerful — but 250W power draw, loud fans, wife said no)
- HP ProLiant ML30 (good for a proper rack setup — overkill for personal lab)
- A spare laptop (works fine for 5–8 nodes — storage I/O becomes the bottleneck)
Network
- Mikrotik hAP ax³ as the home router with VLAN support — Lab VLAN 99 is isolated from the home network
- Cisco SG350 8-port managed switch — VLAN-aware, connects the NUC, physical router, and workstation
- Cisco 891 router (physical, bought used for ~$30) for scenarios where real hardware behavior matters — especially IOS quirks that QEMU emulation doesn't reproduce
The Simulation Stack
I run three simulation platforms, each for different purposes:
The three platforms can coexist on the same ESXi host. I give CML 32 GB RAM (it gets the most use), EVE-NG 16 GB, and GNS3 8 GB. They share the NVMe storage.
Study Resources I Actually Use
The internet is full of Cisco study resources. These are the ones that work for me:
Books:
- CCNP and CCIE Enterprise Core ENCOR 350-401 Official Cert Guide — the foundation. Read it, but don't only read it.
- Routing TCP/IP Vol. 1 & 2 by Jeff Doyle — deeper than any cert guide, explains the why behind BGP and OSPF design decisions.
Video:
- CBT Nuggets CCNP series — good for building mental models, not for hands-on depth
- Nick Russo's YouTube channel (INE guest videos) — best BGP and MPLS deep-dives I've found
Practice:
- Cisco Learning Network — sample exam questions, but limit to final prep
- Building topologies from scratch and troubleshooting them > any video or book
Flashcards:
- Anki with custom decks for CLI commands and RFC numbers — used during commute
My Core Study Topologies
I have three saved CML topologies that I return to repeatedly:
Topology 1 — BGP Multi-AS (CCNP Focus)
4 routers, 2 ASes, eBGP + iBGP full mesh, prefix filtering, local preference, AS path prepending. I practice this until I can build it from memory in under 15 minutes.
Topology 2 — OSPF Multi-Area with Redistribution
OSPF area 0, two non-backbone areas, an ASBR redistributing EIGRP routes in, a stub area, and a totally stubby area. Covers the full OSPF area type comparison.
Topology 3 — ASA Firewall Lab
ASA in single and multi-context mode, NAT (static, dynamic PAT), ACLs with logging, VPN (site-to-site IPsec). I rebuild this whenever I need to refresh firewall skills before a production change.
The Most Important Lab Habit
Lab everything before you touch production.
Every significant change I make in production — BGP policy change, firewall ACL, OSPF redistribution — I build in CML first. Not to prove I know the command syntax, but to confirm the behavior. IOS sometimes surprises you. Better surprised in the lab than at 2am during a P1.
Build the lab, run the change, verify, then write the production runbook from what the lab taught you.
Getting Started — Minimum Viable Homelab
You don't need 64 GB RAM to start. Here's the minimum setup:
The expensive option is the dedicated server with CML. It makes the lab faster and more capable — but it is not required to pass CCNP. Candidates pass every year on a single laptop running EVE-NG.