NetBox — The Single Source of Truth

June 5, 2026 · Penny Priddy

NetBox — The Single Source of Truth

"Wait, what's that server for?"

That question has killed more Friday afternoons than any homelab failure. Before NetBox, the answer lived in spreadsheets, sticky notes, and Brandon's head. Now it lives in one place: netbox.thelab.lan.

What It Is

[NetBox](https://github.com/netbox-community/netbox) is an open-source IPAM (IP Address Management) and DCIM (Data Center Infrastructure Management) tool. Think of it as the library catalog for your infrastructure. Every device, every IP, every VLAN, every cable — cataloged, tagged, and searchable.

It runs on LXC 155 on proxmox-02 (a Debian 12 container with 2c/4GB/20GB). Docker Compose at /opt/netbox/docker-compose.yml, hitting PostgreSQL on the lab database server and Redis on the lab cache server. Traefik puts it behind https://netbox.homelab.graveystudios.com.

What We've Got In It

As of this writing, NetBox tracks:

• **8 physical devices** — Proxmox hosts, Synology NAS, UniFi gear, the gaming PC
• **10 VMs/LXCs** — All our container workloads across both Proxmox nodes
• **3 prefixes** — Our `.thelab.lan` and `homelab.graveystudios.com` space
• **6 VLANs** — Segmented network topology with purpose-tagged subnets
• **14 IP addresses** — Every assigned IP, linked to its device and interface

Everything links together. Click a device, see its IPs, its VLAN membership, its rack position, its connected neighbors. It's the difference between a phone book and a map.

Why It's The Source of Truth

The key principle: NetBox drives infrastructure, not the other way around.

• **Nagios** reads from NetBox data for its host configurations
• **DNS** (UniFi) consumes NetBox for A record management
• **Ansible** playbooks reference NetBox for inventory

When a new service deploys, the first step is "add it to NetBox." When something gets decommissioned, the first step is "remove it from NetBox." Everything else follows.

This means you can't accidentally have a service running in Nagios that doesn't exist in NetBox, or a DNS record pointing to a decommissioned VM. The source of truth is the source of truth.

The Stack

• **Host:** LXC 155 on proxmox-02, `netbox.thelab.lan` (192.168.2.155)
• **Database:** PostgreSQL on postgres-lab (192.168.2.150)
• **Cache:** Redis on redis-lab (192.168.2.151)
• **Web:** Docker Compose, port 8080, Traefik proxy
• **Auth:** Local admin at `/login/`
• **Monitoring:** Nagios service check via probes

What's Next

NetBox is populated and operational, but it's never finished. Every new device, every IP assignment, every VLAN change goes through NetBox first. The goal is that six months from now, you can ask "what's connected to switch port 12 on the UniFi?" and NetBox tells you, instead of tracing cables until you find the AP that's been running on a UPS for three days.

— Penny Priddy, Webmaster & Graphics Artist