Mint: Timeshift to a NAS?

[SoreTween]

I'm trying to use timeshift to backup a mint laptop to a folder on my NAS.  So far these parts have gone OK:

Created a new share in my public\computerbackups folder on the NAS
Created a user on the nas who only has permissions to access that share
Created a mountpoint on the laptop
Fiddled with /etc/fstab including credentials= to...
Created a credentials file in my /home/<ME> with appropriate permissions.

All good, reboot and I can see the folder.  But timeshift doesn't list folders as destinations for backups - arse!  Perfect success, I just set out to do the wrong thing Is there a way to make my network location appear to be a locally mounted volume?

I think timeshift is the right program to be using, I don't need to backup user files, (those are already backed up) just the system.

Thanks

[Kim]

I hadn't heard of timeshift (I use rsync and borg) but the first thing that I'd question was whether root can access the network share properly (I assume timeshift runs as root in order to access what it needs to back up, and you don't specify what network filesystem you're using)?

[SoreTween]

Timeshift is a made-for-idiots (that's me!) system backup utility that ships with Mint recommended in the Mint upgrade guide.  I'm getting my ducks lined up before upgrading to mint 19.

It appears permissions are ok.  If I sudo -i then whoami says I'm root, I can then list and copy files in /media/<mountpoint> just as I can as <me>.  The network username and password set on the NAS and stored in the credentials file matches neither me nor root but it appears to be working for a root interactive session, would it therefore for a root service session?  Timeshift does ask for my password when I run it but that's my superuser password. 

<aside>
If I was asked to set up a password for root when I installed Mint a couple of years ago then it's time to Hicks the drive and install 19 fresh instead of upgrading, no idea what it was!  I'll be surprised, I have a truecrypt volume in which I keep all my passwords in a text file, I do occasionally forget to note one...
</aside>

Network filesystem, ummm.  The NAS is a QNAP and runs a flavor of linux but it can do windows shares too, could be anything!  It's not specified in the settings of the share.  If there's a higher level default setting on the NAS that I can't find at the moment it is likely to be set to windows flavoured shares.  Is there something I can run on the minttop to tell?

[Kim]

Probably not that problem then.  (I was thinking of the root_squash option for NFS, which generally prevents root on the client from being able to do anything useful, in order that someone on J Random machine can't access the entire server simply by claiming to be root.  The NFS security model is pretty rudimentary, being designed for a computer lab type environment.)

Network filesystem: There are various ways of mounting filesystems over the network.  NFS is traditional, but SMB/CIFS is used by Windows machines, and as such has become well-supported by graphical Linux environments over the years.  Also exotica like SSHFS, which is useful over the internet, or for one-off use.  Basically, whatever you've put in the third column in /etc/fstab for the mount.

(Not the same thing as the filesystem the server is using internally.  Which could be anything, and you don't usually need to care about.)


(Passwords are hashed, so you won't be able to find out what it is, but you can always change the root password by running 'passwd' with sudo.  Of course, sudo makes the root password mostly irrelevant.  I think it's mostly useful for when something goes horribly wrong to stop the machine booting properly and you need to access single-user mode.)

[SoreTween]

Ah, thanks Kim, CIFS.