This is an independent community resource about Dia. We are not affiliated with the GNOME Dia project. Rack shape packages mentioned here are community contributions, not officially endorsed by any vendor.
How to Draw Server Rack Diagrams in Dia
Every sysadmin knows the pain: a rack full of servers and nobody remembers what lives in U12. A rack diagram — a to-scale drawing of each rack unit — is the fix, and Dia is one of the best free tools for making them. This tutorial covers installing rack shape packages and laying out a clean 42U diagram.
Step 1 — Install Rack Shapes
Dia’s built-in Network sheet covers routers and switches, but for rack elevations you want the community “Central Data Processing” shape package from the Dia Shape Repository (it includes 42U rack frames, 1U–5U servers, patch panels and PDUs). Install it with the Diashapes wizard, or manually:
- Download the shape package (.zip) from the repository.
- Extract it into Dia’s shapes directory (on Windows:
C:\Users\<you>\.dia\shapes; on Linux:~/.dia/shapes). - Restart Dia, then File > Sheets and Objects — enable the new sheet.
See our custom shapes guide for the full walkthrough.
Step 2 — Build the Rack Frame
Place a 42U rack frame object on the canvas. This is your canvas-within-a-canvas: everything else stacks inside it. Set View > Snap to Grid on — U alignment is the whole point of a rack diagram, and the grid keeps 1U servers from drifting.
Step 3 — Fill the Units
Working top to bottom (or bottom to top — pick one convention and stick to it):
- Place patch panels at the top (typically U42–U40).
- Place switches just below the patch panels for short cable runs.
- Place servers (1U/2U) in the middle band, heaviest at the bottom for stability.
- Place PDUs and UPS at the very bottom.
- Leave documented empty units as blank 1U spacers — “empty” is information too.
Step 4 — Document Cabling (Optional but Valuable)
Use Dia’s orthogonal line tool to draw cable runs between patch panels and switches, color-coding by function (blue = data, yellow = management, red = console). Keep cable lines on a separate layer (Diagram > Layers) so you can hide them when you only want the elevation view.
Step 5 — Export and Share
Export as PDF for the runbook binder and PNG for the wiki. Re-export whenever hardware changes — a stale rack diagram is worse than none.
Document Your Racks Free
Dia runs offline on the admin workstation — no cloud, no subscription.
Download Dia Network Diagram TutorialFrequently Asked Questions
Are the Cisco shapes official?
No. Community-made shapes inspired by Cisco iconography are widely used for documentation, but they are not licensed or endorsed by Cisco. Fine for internal docs; check your company’s policy for client-facing material.
Can I show front and rear views?
Yes — duplicate the rack frame on a second page (Diagram > Add Page) and label one FRONT and one REAR. Multi-page printing keeps them together.
How do I keep diagrams in sync with reality?
Discipline, not software: make “update the rack diagram” part of your change procedure. Store the .dia file next to your inventory docs.
Can I import from a CMDB or spreadsheet?
Not automatically — Dia has no CMDB import. For generated diagrams from live data, a scripted tool (or Dia’s own Python scripting) is the path.