Keep the notebook running when the lid is closed

Recently i repurposed my old Lenovo P50 (2 x 1TB SSD, i7-6820, 64 GB RAM) to become my 'personal' proxmox-cluster.

Had one little annoyance: closing the lid causes the P50 to go into sleep mode - not that helpful, because you usually don't work directly on the prox..

Long story short - after searching the web a very simple and smart solution:

First let's look at the acpi table

root@pve:~# cat /proc/acpi/wakeup | grep "LID"
LID       S4    *enabled   platform:PNP0C0D:00

Nice, now let's disable this one - dry run in the shell:

echo 'PNP0C0D:00' | tee /sys/bus/acpi/drivers/button/unbind

And close the lid. Your prox is still available? Goood!
Final step: Create a file (if it does not exist..) /etc/rc.local, add the command from above with a little yada.

#!/bin/bash
echo 'PNP0C0D:00' | tee /sys/bus/acpi/drivers/button/unbind
exit 0

Save it, make it x-able - reboot, test - should work.