Managing systemd.mount timeout gracefully

[ytene]

With the spike in domestic electricity costs, one of the measures I've taken to try and reduce consumption is to employ the "Power Schedule" feature of my QNAP NAS. I have a pair of QNAP devices, a TVS-672 which serves as my primary, and a TS-670, which I use as a backup. I have backup jobs on the former that run on a schedule and push copies of my critical files to the 670.

Using "Power Schedule", I've set my 670 to switch itself on at 01:30 every morning and switch off again at 05:00, giving plenty of time for various backups to run.

So far, so good.

But prior to this, I had both my 672 and my 670 referenced in the fstab file on my Mint workstation. The mount statement for my 670 was as follows:-

172.16.101.1:Data /media/670 nfs rw,hard,intr 0 2

Of course this works, but with the 670 now powered off most of the time, I'm left waiting for the mount utility to time out and declare the device unavailable... So I decided to tweak the mount string, changing it to this:-

172.16.101.1:Data /media/670 nfs rw,hard,intr,nofail,x-systemd.device-timeout=10s 0 2

I've tried this with and without the second marker ('s'), but so far I've been unable to get the additional guidance to work as expected. I say "as expected" only in that I've used this syntax successfully on a Raspberry Pi, running Raspbian (another Debian derivative) and it works just fine. Obviously the x-systemd.device-timeout is not a mount parameter, but I've not found anything helpful in man pages to give me a hint as to where I might be going wrong.

What happens (when trying "sudo mount - a" to test the configuration) is that I get a delay in the mount process that seems to be just shy of 2 mins 15 seconds in length, then the message "mount.nfs: Connection timed out" appears.

Obviously this is not a major issue... All I need to do is to revert the mount string to original syntax, but comment it out with a '#' character. I'm just curious to know if anyone can suggest where I went wrong with the device-timeout statement please?

Thanks in advance.