Thanks @mstormi for taking the time to answer. I know you already told me this was not the recommended way. I will understand perfectly that you do not waste time to answer my questions.
I do find advantages and easyness with the NFS mounted system partition : switching from one config to the other, easily save the entire config, try something and then come back with a just a mv command on the NAS and a reboot, without manipulating SD cards - as my raspberries are in the basement.
Also, I had the feeling that Raspberry OS was evolving in the direction of allowing more things from the network e.g. network boots are now supported out of the box… I thought I had read a lot on the topic and did not encounter recommendations (out of openhabian context for not using this type of config).
As for the “move root to USB”, you are right I looked at it too fast and it was the SD mirroring script. I looked at the move_root2usb() function and it is rsync -axv that is used.
But at this stage I really need to run more tests as I was not patient enough to properly test all scenarios as per Rich suggestions to understand where exactly my problem is coming from.
Just to be complete, there are lots of ways to achieve all of these that do not involve a NAS and NFS mounting. The fact that your RPis are not easily accessed is irrelevant. One approach could be to use VSCode and the RemoteSSH add-ons which make it as if you are working on that remote machine. I think it supports RPis now. With that you work on that machine as if you were sitting at it, including getting a terminal, copying files around and all that sort of thing. And that’s just one approach. Others can include sharing the config folders from the RPi instead of to the RPi. Yet another approach could use git or some other source control software.
The end goal of openHABian is first and foremost reliability. And as Marcus states, the more moving parts you have, the less reliable your overall system becomes. With an NFS mounted file system you greatly increase the unreliability and end up with a bunch of additional problems and limitations for your trouble (what if the NAS goes down? file permissions and ownership, what if the NAS is down when the RPi boots? etc.). About the only thing that the NAS provides from a reliability perspective is it limits SD card wear out, and the ZRAM configuration manages that by itself with fewer moving parts.
Personally, while not doing this for OH, I used to run a number of services off of an NFS mount. I’ve disabled them all except for Plex and Nextcloud as being more trouble than they are worth (I’ve only kept Plex and NC on the NFS mount in part though to store the big files that don’t change much), settling on backup and restore scripts and stuff like that to keep things safe and reliable.
Hello Rich, sure I use all those SSH, VS code + remote SSH addon etc…, of course.
I was referring to quickly switch from one test config to the prod config, for example, without having to switch SD cards.
