MCU ‘mcu’ shutdown: Timer too close 45 minutes into a print

Basic Information:

Printer Model: Ender 5 Plus
MCU / Printerboard: BTT SKR Mini E3 V3.0
klippy.log (3.1 MB)

Describe your issue:

45 minutes into a print, just got that error, first time doing a long print with klipper.
Here was the hardware status of the last hour or so.

All seems good.

The graphs you are showing look suspicously like Proxmox. If so, nothing is good: Running Klipper in a Virtual Machine (VM)

Yeah, it is in proxmox. Basically I only had one available machine so I decided to slap that in with USB passthrough, I got those errors.

How I solved it, using Q66’s solution from the klipper discord:

  1. I had a old RPI 2B. Install Ser2Net on it, forwarded the serial connection over TCP.
  2. On the klipper Host, installed Socat to connect to the TCP Socket and output the serial to /dev/pts/2
  3. Change printer.cfg to /dev/pts/2 for MCU.

This basically tunnels in the serial via IP.

It’s been working wonderfully since then. Klippy logs shows that MCU_TASK_AVG and mcu_task_stddev have both dropped by about 75%.