© Made by Adam Bellanger

A secure business network lab: FortiGate, Huawei switches, five isolated VLANs, IPsec VPN and monitoring.

LabA lab: designed and documented end to end, modelled on the installations I work on as an apprentice. Not a client engagement.

Stack

Networking
  • FortiGate
  • Huawei VRP
  • VLAN 802.1Q
  • LACP
  • IPsec
  • DHCP Snooping
  • SNMP
Infra
  • Grafana

Context

Same fictional company: 40 employees, IP telephony, guest Wi-Fi, cameras and travelling sales staff. The starting point is a flat network behind the ISP router: one infected laptop or one curious guest can see every camera and the file server.

Role

Lab project: addressing plan, VLAN design, filtering policy, device configuration and operations documentation. These are the devices and settings I work with as an apprentice.

Architecture

  1. Internet

    FTTO fibre + 4G backup

  2. FortiGate

    Inter-VLAN routing, filtering, IPsec VPN

  3. Huawei core switch

    LACP bundle to the FortiGate

  4. PoE access switches

    One per floor, 802.1Q trunks

  5. VLAN 10 · Data

    Workstations and file server

    VLAN 20 · Voice

    IP-PBX and phones

    VLAN 30 · Guests

    Wi-Fi, Internet only

    VLAN 40 · Video

    Cameras and NVR, isolated

    VLAN 99 · Admin

    Device management

Remote work: FortiClient over IKEv2 IPsec. Monitoring: SNMPv3 from the switches and FortiGate, fed into Grafana through Prometheus.

Addressing plan

VLANNameNetworkAllowed access
10Data10.10.10.0/24Internet, file server, printers
20Voice10.10.20.0/24IP-PBX and carrier SIP trunk only
30Guests10.10.30.0/24Internet only, Wi-Fi client isolation
40Video10.10.40.0/24Recorder (NVR) only, no Internet
99Admin10.10.99.0/24Device management interfaces

Challenges

Isolating without getting in the way: inter-VLAN routing on the FortiGate with explicit rules (guests only reach the Internet, cameras only talk to the recorder, management is only reachable from its own VLAN); making the core-to-firewall link resilient with LACP; hardening access ports (DHCP snooping, BPDU protection, unused ports shut down); and giving remote staff clean access over IKEv2 IPsec with FortiClient rather than SSL VPN, which Fortinet is phasing out.

Outcome

A segmented, documented network: addressing plan, allowed-flows matrix, backed-up configurations and SNMP monitoring of every device in Grafana (throughput, port status, uptime). Every rule has a written reason, which makes operations and support much simpler.

Highlights

  • 5 isolated VLANs, inter-VLAN routing filtered by the FortiGate
  • Core ↔ firewall link in LACP (2 × 1 Gb/s)
  • Hardened access ports: DHCP snooping, BPDU protection, unused ports shut
  • IKEv2 IPsec VPN for remote staff, SNMP monitoring in Grafana
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