HW Watchdog Setup

UGREEN NAS Hardware Watchdog
Before installing another OS, you'll need to temporarily disable the watchdog in the BIOS. Whichever live disk is being used likely doesn't support it, and the newly installed OS won't support it either until we configure it.
Boot the NAS, and right when the 
UGREEN logo shows up, hold 
ctrl and press 
F12 a few times to get to the boot menu
Choose 
setup (last item in the list)
Under the 
FAST tab, change the watchdog unit from 
second to 
disabled
After the watchdog is correctly configured in the new OS, you can reenable the watchdog by reverting step 3.
systemd-based linux systems
Pulling the disk off the NAS, the second partition is the squashfs used as the base for the overlayFS. The watchdog is setup to be fed in systemd, and the config for that is in 
/etc/systemd/system.conf:
[Manager]
RuntimeWatchdogSec=120
RuntimeWatchdogPreSec=off
RebootWatchdogSec=2min
KExecWatchdogSec=off
WatchdogDevice=/dev/watchdog
DefaultTimeoutStopSec=30s
So for any other OS, we'll need to confirm that the watchdog is found and is at 
/dev/watchdog, then this same config should work.
If the 
it87_wdt module is not automatically loaded, you'll need to install a watchdog daemon, such as 
watchdog, which will detect and load the correct module. If that still doesn't automatically load it, you can also add 
it87_wdt to 
/etc/modules.
Reboot and confirm the watchdog is found by checking 
dmesg, or running 
wdctl, you should see 
IT87 mentioned somewhere
Proxmox
Proxmox's high availability services already contain functionality to manage the watchdog.
First, ensure the following services are enabled:
systemctl enable pve-ha-lrm
systemctl enable pve-ha-crm
systemctl enable corosync
These will in turn enable the 
watchdog-mux service, which can be configured to load the correct module.
Edit 
/etc/default/pve-ha-manager to contain the correct module:
# select watchdog module (default is softdog)
WATCHDOG_MODULE=it87_wdt
Reboot and confirm the watchdog is found by checking 
dmesg, or running 
wdctl, you should see 
IT87 mentioned somewhere