Best way to create backup on cloud for EPUB books

[Sirtel]

As I have no plans to change platforms, folder sync will remain my preferred method.

[ownedbycats]

Originally Posted by BetterRed

The only thing I've ever needed to recover from a calibre library backup is an individual book or format file because of a mistake by me. That cannot be done directly from a set of spanned archives created by calibre's export function. Whereas it can be done directly from a copy of the library maintained by any one of several file sync tools.

Yes, same here - the last time was only half-user error, the file-locking change resulted in a book format getting eaten. Restored the individual file from a backup.

[Quoth]

I'm totally in favour of regular file-sync to backup.

[DNSB]

For my purposes, single file recovery is done from my normal backup sets so I see no need for a separate backup for calibre libraries and settings. Basically, an incremental backup from Tuesday to Sunday and a full backup on Monday with a 3 set rotation. The backups are stored on the NAS and an external hard drive since I don't feel up to pushing that much data to the Internet.

The calibre export/import are more for when I spin up a new VM and install calibre on it which I probably do too often—does anyone really need access to 6 Linux distros, Windows 11 Insider Preview and two MacOS VMs at home?

[Sweetpea]

I've been using OneDrive for a few years now. Not necessarily as backup, but more because I use multiple windows devices (though never at the same time). I just point Calibre to my OneDrive folder when I install a new PC. This has the side benefit that I always have access to my books, wherever I have an internet connection, even if I don't have access to Calibre...

[ownedbycats]

Originally Posted by Sweetpea

I've been using OneDrive for a few years now. Not necessarily as backup, but more because I use multiple windows devices (though never at the same time). I just point Calibre to my OneDrive folder when I install a new PC. This has the side benefit that I always have access to my books, wherever I have an internet connection, even if I don't have access to Calibre...

No! no!!!! This is how Calibre databases get corrupted!!!!!

[Sweetpea]

Originally Posted by ownedbycats

No! no!!!! This is how Calibre databases get corrupted!!!!!

I'll wait for it then, as I've been doing it for at least 9 years already and never had any corruption...

[Sirtel]

Originally Posted by Sweetpea

I'll wait for it then, as I've been doing it for at least 9 years already and never had any corruption...

Have you run a library check?

[DNSB]

How many posts have we seen where someone has been using a NAS or cloud storage and opens with <paraphrased> "I've been using a NAS/cloud service to store my calibre library for years and suddenly my calibre library/database is corrupted and I've lost many books"

If @Sweetpea is being very careful with not connecting from more than one calibre instance and has a good Internet connection, they might not see issues. OTOH, it's an unnecessary risk IMNSHO.

[BetterRed]

Originally Posted by JSWolf

Why would an export be better when moving platforms? I cannot see an export being any better then syncing the library and settings to this new platform.

Calibre export/import will take care of any platform differences in the database or more likely the configuration files, I sooner trust Kovid to know about those differences than me.

Pre export/import I recall helping someone to move from Linux to Windows, can't recall the details but the calibre move it wasn't smooth sailing. Since then I've used import/export to move from calibre from Windows to Mac, and Linux to Mac without issue.

BR

[Sweetpea]

Originally Posted by DNSB

How many posts have we seen where someone has been using a NAS or cloud storage and opens with <paraphrased> "I've been using a NAS/cloud service to store my calibre library for years and suddenly my calibre library/database is corrupted and I've lost many books"

If @Sweetpea is being very careful with not connecting from more than one calibre instance and has a good Internet connection, they might not see issues. OTOH, it's an unnecessary risk IMNSHO.

Considering I can't work on two devices at the same time, the chances of me having the library open at both devices at the same time is close to zero. One is my PC, a fixed device that is living in my house and never leaves it. The other is on my laptop which I use when I'm away from home. Or don't want to fire up my PC.

@Sirtel, I just did: no errors in my database.

[Sirtel]

Originally Posted by Sweetpea

Considering I can't work on two devices at the same time, the chances of me having the library open at both devices at the same time is close to zero. One is my PC, a fixed device that is living in my house and never leaves it. The other is on my laptop which I use when I'm away from home. Or don't want to fire up my PC.

@Sirtel, I just did: no errors in my database.

It doesn't need to be at the same time. Any back and forth syncing from more than one device (not necessarily at the same time) will eventually mess up your library. I've done it and had to check my library every time, and fix any errors that had appeared. With Dropbox it worked; with OneDrive I flat out lost several files before I ditched OneDrive altogether.

Did you run the extended check to see if your database matches the actual files? The initial check almost always returns no errors, regardless whether there actually are any or not.

[DNSB]

Originally Posted by Sweetpea

Considering I can't work on two devices at the same time, the chances of me having the library open at both devices at the same time is close to zero. One is my PC, a fixed device that is living in my house and never leaves it. The other is on my laptop which I use when I'm away from home. Or don't want to fire up my PC.

You can run into issues if for example, you have calibre open on your PC and don't close it before leaving home. You leave home, start calibre on your laptop and, ooopppsss, two devices are accessing the database. That was why the comment about being careful not to connect from more than one calibre instance in a previous message.

Sadly, close to zero is not zero.

[Quoth]

Originally Posted by DNSB

The calibre export/import are more for when I spin up a new VM and install calibre on it which I probably do too often—does anyone really need access to 6 Linux distros, Windows 11 Insider Preview and two MacOS VMs at home?

Yes, but not many as a percentage of users. However there are a lot of computer users.

[Sweetpea]

Originally Posted by DNSB

You can run into issues if for example, you have calibre open on your PC and don't close it before leaving home. You leave home, start calibre on your laptop and, ooopppsss, two devices are accessing the database. That was why the comment about being careful not to connect from more than one calibre instance in a previous message.

Sadly, close to zero is not zero.

When I leave home, I turn off my PC. So, it'll be closed. Besides, I only start Calibre when I buy new books and want to put it on my device. Which I 99,999% of the time do behind my PC. And only rarely on my laptop.

The problem with advice such as "never do it because it will ruin your thing 100% of the time" is that it is very user dependent. I'd rather say: if you use Calibre on a regular basis on multiple devices, be either very careful or use another method. If you use Calibre mostly on one device and very rarely on the other, again be careful, but it is an easy way of backing it up while syncing at the same time.