-> Same for me, my 2nd WD N750 still run with that version without any problems...
QUESTION IS STILL PENDENT: Is there a customized (custom compiled) v21.x or v22.x version for the WD N750 which has a fix / bypass / workaround for that issues...?
I'm sorry I can't help with further details. I have been running version 22 on 4 devices. I have been posting updates in the threads about any issues. 1 2 have experienced 0 issues since flashing (it has the least config/file changes). Longest Uptime: 20+ days thus far (was on Solar/battery and I disconnected yesterday to maintenance the battery).
The 2nd I used a custom firmware (with the packages I need pre installed) I had no issues until one day LuCI and CLI stopped responding except to busybox. I rebooted and installed a firmware without LuCI. Uptime: 17 days so far.
I remotely sysugraded Device B from 22.03.0 to 22.03.1. It did not have LuCI installed in the image. The device did not seem to reboot successfully. I'm waiting on remote hands at the location to troubleshoot. I'll update soon.
I was told in another thread to announce if such things occur. Not sure why the OP assumed I upgraded the other machine; but nonetheless - in this case I in fact did upgrade the N750 and I am noting the issue.
On this failed flash, I added to the Firmware Selector:
wireguard-tools kmod-wireguard snmpd tcpdump
This produced an image without LuCI
I upgraded another device today (Device C) - after looking at the file sizes of all packages. tcpdump adds nearly 1 MB additional including its dependencies. So I only added:
wireguard-tools kmod-wireguard snmpd
This again made an image without LuCI - that upgraded successfully.
So it's definitely the image size causing issues. I'm guessing when luci-ssl became the default web GUI is when most people not adding packages started noticing.
Additional question: How is that possible that something that runs on application layer (Luci) will make a difference on such "low-level"-Filesystem errors?