I am currently using GNOME Backups (aka Déjà Dup Backups) to backup all my files to a "backups" folder in my Dropbox. This is not a good solution - first because I want to stop paying for dropbox, second because I don't want to keep everything in the cloud, third because everything is stored twice on my laptop and storage is precious.
I therefore want to manage back-ups locally instead. I would like to keep using Déjà Dup, as it has worked really well and effortlessly.
My initial idea is very bare bones. I could keep an old laptop running 24/7, connect a hard drive, and use SSH file transfer in Deja Dup in order to store everything on that machine. That said, I have a few concerns as well.
Is this a good way of doing things? Should I be doing something else instead?
I'm not always at home - will it be a problem if the Backup software cannot find the folder because it's not on the correct network, or will it have the sense to wait until it's connected to the correct wifi?
Will the old laptop use a lot of power, or is it regrettable for any other reason? Is it possible to make it automatically hibernate for example during the nigthtime? Or to have it spend very little power unless anything is connected via SSH?
Would it be better to get a dedicated device, like a Rasberry Pi or something? I don't have all too much faith in my old laptop not making noise with the fan running at random times.
It looks like my partner will be getting a new laptop running Linux soon enough as she has to hand in her work computer, so it would be good timing to get a proper solution into place.
Your best advantage with dropbox is that it's not at home.
Backups tend to play their biggest role when something catastrophic has occurred such as a house fire, theft or ransomware.
Laptops are typically built with power efficiency in mind, so as long as you've configured it to save power it should be fine. Look into a feature set called "Advanced Power Management".
Your #2 question has some ambiguity. It's ultimately influenced by how you're configuring it and what tools you'll be using. I'm not familiar with the tool you mentioned.
For your question #4. Keep in mind that you'll need to factor in the age of hardware and confirm the health of the HDD. Having a newer piece of hardware controlling the show like a pi would possibly be more reliable but there's too many unknowns here to be certain.
Since you're working with just Linux systems you could probably get away with copying the /home partition and storing it in multiple places.
It's wise to check hash values of the files copied to confirm they didn't get corrupted in flight.
It's also possible that you'll encounter insidious malware that intentionally messes with your backups. So if you're using SSH for example it may attempt to use the stored credentials to do awful things to the server.
So using a service like crashplan for critical stuff might be easier.
I would get a new hard drive, so the laptop would just be in charge of managing the backups. So if it fails it only needs to be replaced, but the backup itself wouldn't be lost.
And yeah, this is why I'm a bit reluctant to set up SSH access beyond the home network, other than of course my lack of competence to do so. I am fairly certain everything going on inside my home network is safe enough for my risk profile (holiday pictures, half baked articles, and shitty R scripts, mostly).
But the not at home argument is of course a good point, and one that I knew about but somehow neglected. I want to avoid the cloud, but I think I will set up a separate backup at work. :)
Thanks for the comment - it's a really good checklist of things to be aware of going forward!