Why is my Klipper-powered printer offline?

Written By Albert Møller Nielsen

Last updated About 8 hours ago

Why is my Klipper-powered printer offline?

This guide helps troubleshoot why your Klipper-based printer shows offline in SimplyPrint.

How SimplyPrint connects

SimplyPrint connects through Moonraker - not Klipper directly.

SimplyPrint ←→ Moonraker ←→ Klipper ←→ Printer

Mainsail and Fluidd also talk to Moonraker. If they can control your printer, Moonraker is working.

Start here: Where is the problem?

Step 1: Can you access Mainsail or Fluidd?

Open your printer's web interface in a browser.

  • Can't access it? → Your printer or Moonraker has issues - not a SimplyPrint problem
  • Can access it and printer works? → Continue to Step 2

Step 2: Is [simplyprint] in moonraker.conf?

In Mainsail or Fluidd, open the config editor and check moonraker.conf for:

[simplyprint]

Step 3: Check moonraker.log for errors

Download moonraker.log from Mainsail/Fluidd and search for "simplyprint".

Mainsail: Machine > Logs > moonraker.log (download icon)

Fluidd: Settings > Logs > moonraker.log

Quick reference

SymptomLikely causeSolution
Printer never connected[simplyprint] missingAdd to moonraker.conf
Was working, now offlineMoonraker restarted or config changedRestart Moonraker
"Klippy not connected" in Mainsail/FluiddKlipper issue (not SimplyPrint)Fix Klipper first
Offline after power outageServices didn't startRestart services
SimplyPrint errors in logsVariousCheck common errors

1. Add [simplyprint] to moonraker.conf

Using Mainsail or Fluidd

  1. Open config editor
  2. Open moonraker.conf
  3. Add this line anywhere:
[simplyprint]
  1. Save
  2. Restart Moonraker
Note: That's all you need - just [simplyprint] with nothing else. The component is built into Moonraker.

Component doesn't work?

Your Moonraker may be outdated. Update using the update manager in Mainsail/Fluidd.

2. Restart Moonraker

First: Try restarting Moonraker - this fixes many connection issues.

Many issues are fixed by restarting after config changes.

Mainsail: Power icon (top right) > Restart Moonraker

Fluidd: Settings > Services > Restart Moonraker

Make sure you saved config changes before restarting.

3. Common errors in logs

Download moonraker.log and search for "simplyprint":

Error Meaning Fix
"Connection failed" Can't reach SimplyPrint servers Check internet connection
"Klippy Host not connected" Klipper isn't running Fix Klipper first
"Authorization error" Moonraker blocking connection Check [authorization] in moonraker.conf
No SimplyPrint entries Component not loaded Add [simplyprint] and restart

4. Network issues

Internet connection

Your printer needs internet for SimplyPrint. If Mainsail/Fluidd works but SimplyPrint doesn't, check connectivity.

WiFi stability

Unstable WiFi causes random disconnections:

  • Try Ethernet instead
  • Move closer to router
  • Check for interference

Firewall

SimplyPrint connects outbound - no ports need opening. But make sure outbound connections aren't blocked.

After a power outage

Services may not have started correctly.

  1. Check if you can access the web interface
  2. If yes, restart Moonraker from interface
  3. If not, wait a few minutes for boot to complete

Advanced: SSH troubleshooting

If you have SSH access:

Check if Moonraker is running:

systemctl status moonraker

Restart services:

sudo systemctl restart moonraker

View logs:

tail -100 ~/printer_data/logs/moonraker.log

Getting help

Gather this first

  1. Download moonraker.log from Mainsail/Fluidd
  2. Copy moonraker.conf (remove sensitive info)
  3. Screenshot of offline printer in SimplyPrint
  4. What you've tried

Support

Something unclear or missing in this guide? Let us know on Discord.

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