How do you backup?

Offline Backup on 2 separate HDD/SSD
Backup on HDD within my desktop pc
Backup offsite with restic to Hetzner Storage Box

I use Duplicacy to backup to my TrueNAS server. Crucial data like documents are backed up a second time to my GDrive, also using Duplicacy. Sadly it's a paid solution, but it works great for me.

I use external drive for my important data and if my system is borked (which never happen to me) I just reinstall the OS
- External drives are more prone to damage and failures, both because they're more likely to be dropped/bumped/spilled on etc, and because of generally cheaper construction compared to internal drives. In the case of SSDs the difference might be negligible, but I suggest you at least make a copy on another "cold" external drive if the data is actually important

Borg Backup, whenever I feel like it - usually monthly.

I have a server with a RAID-1 array, that makes daily, weekly, and monthly read only btrfs snapshots. The whole thing (sans snapshots) is sync'd with syncthing to two rPi's in two different geographic locations.
I know neither raid nor syncthing are "real" backup solutions, but with so many copies of the files living in so many locations (in addition to my phone, laptop, etc.) I'm reasonably confident its a decent solution.

Using timeshift. Very, very easy, works great.

My KVM hosts use “virsh backup begin” to make full backups nightly.
All machines, including the KVM hosts and laptops, use rsync with --link-dest to create daily incremental versioned backups on my main backup server.
The main backup server pushes client-side encrypted backups which include the latest daily snapshot for every system to rsync.net via Borg.
I also have 2 DASs with 2 22TB encrypted drives in each. One of these is plugged into the backup server while the other one sits powered off in a drawer in my desk at work. The main backup server pushes all backups to this DAS weekly and I swap the two DASs ~monthly so the one in my desk at work is never more than a month or so out of date.

All my configs are in gitlab or a self hosted forgejo server and all files are in seafile or a self hosted service running on proxmox. Then I use proxmox backup server on a storage VPS for off-site backup

Backup? What?
- Your car.

Right now, nothing 😈 (but my dotfiles/etc configs live on several machines)
Before, I used Restic (incremental, encrypted backup over network), which I really liked. I think I should set it up again.

daily important stuff (job stuff, Documents folder, Renoise mods) is kept synced between laptop, desktop and home server via Syncthing. A vimwiki additionally also syncs with the phone. Sync happens only when on home network.
the rest of the laptop and desktop I'll roll into a tar backup every now and then with a quick bash alias. The tar files also get synced onto home server's big file system (2 TB ssd) via Syncthing. Home server backs itself up on it's own once a week.
clever thing is that the 2 TB ssd replaced an old 2 TB spinning disk. I kept the old disk and set up a systemd thing that keeps it spun down, but starts and mounts it once a week and rsyncs the changes to the ssd over, then unmounts it so that it sleeps again for a week. That old drive is likely to serve for years still with this frugal use.

Borg to a NAS.
500GB of that NAS is "special" so I then rsync that to a 500GB old laptop hdd, of which is is duplicated again to another 500GB old laptop hdd.
Same 500GB rsync'd to Cloud Server.

My kmymoney file goes on an old compact flash memory card.
My home directory (including that file), /etc, databases, and a few other things get backed up weekly on to a USB stick.
Media raid array is automatically backed up to a large drive in another computer each evening. (The raid5 array isn't that large. It was when I built it, but now I can buy a single drive that is nearly as large as the array...)
Pictures are backed up to Amazon's glacier deep freeze. I pay about $1/month to back up all of my pictures. I intend to put other important things there too but haven't gotten there yet.

My conclusion after researching this a while ago is that the good options are Borg and Restic. Both give you incremental backups with cheap timewise snapshots. They are quite similar to each other, and I don't know of a compelling reason to pick one over the other.
- As far as I know, by definition, at least restic is not incremental. It is a mix of full backup and incremental backup.

i do backups of my home folder with Vorta, tha uses borg in the backend. I never tried restic, but borg is the first incremental backup utility i tried that doesnt increase the backup size when i move or rename a file. I was using backintime before to backup 500gb on a 750gb drive and if I moved 300gb to a different folder, it would try to copy those 300gb again onto the backup drive and fail for lack of storage, while borg handles it beautifully.
as an offsite solution, i use syncthing to mirror my files to a pc at my fathers house that is turned on just once in a while to save power and disc longevity.

My systems are all on btrfs, so I make use of subvolumes and use brkbk to backup snapshots to other locations.
- Same! This works really well.

I use BorgBackup with Vorta for a GUI, and I keep the 3-2-1 backup rule for important stuff (IE: 3 copies, 2 on different media, 1 off-site.)

I want to say I'm glad you asked this and thank you for asking. In this day and age there are a lot of valid concerns for privacy and anonymity and the result is that people do not share how their system(s) work, not openly or very often. I'm still fairly new to Linux (3.5 years) and at times, I feel like I am doing everything wrong and that there is probably a better way. Posts like these help me learn about possible improvements or mistakes I might have made.
I previously used Vorta with Borgbackup locally, automatically backing up my Home (sans things like .cache and .mozilla) to a secondary internal drive every other day. I also would manually back up a smaller set of important documents (memes and porn #joke) to a USB flash drive, to keep on my person, which also would be copied across several cloud storage providers (dropbox, mega, proton), depending on how much space their free versions provided, with items removed according to how much I trusted the provider.
Then I built a new system. In the process of setting it all up, I had a few hiccups. It took longer than I expected to have a stable system. That was over a year ago (stat / ...Birth: 2024-02-05 04:20:53...) and I still haven't gotten around to setting up any backup system on it. I want to rethink my old solution and this post is useful for learning about the options available. It's also a reminder to get it done before it is too late. Where I live, tornado season in starting. I lost a lot in 2019 after my city had 4 tornados in one day.

I rsync ~/ to a USB nub. A no brainer.

Since most of the machines I need to backup are VMs, I do it by the means of hypervisor. I'd use borg scheduled in crontab for physical ones.

I've found that the easiest and most effective way to backup is with an rsync cron job. It's super easy to setup (I had no prior experience with either rsync or cron and it took me 10 minutes) and to configure. The only drawback is that it doesn't create differential backups, but the full task takes less than a minute every day so I don't consider that a problem. But do note that I only backup my home folder, not the full system.
For reference, this is the full line I use: sync -rau --delete --exclude-from='/home/
<myusername>
/.rsync-exclude' /home/
<myusername>
/mnt/Data/Safety/rsync-myhome
".rsync-exclude" is a file that lists all files and directories I don't want to backup, such as temp or cache folders.
(Edit: two stupid errors.)
- Rsync can do incremental backups with a command-line switch and some symlink jugglery. I'm using it to back up my self-hosted stuff.
- You might be interested in "rsnapshot" which uses rsync and manages daily, monthly, etc. snapshots.
- only drawback is that it doesn't create differential backups
  This is a big drawback because even if you don't need to keep old versions of files, you could be replicating silent disk corruption to your backup.
  
  It’s not a drawback because rsync has supported incremental versioned backups for over a decade, you just have to use the --link-dest flag and add a couple lines of code around it for management.

rsync 😪

This looks a bit like borgbackup. It is also versioned and stores everything deduplicated, supports encryption and can be mounted using fuse.
- Thanks for your hint towards borgbackup.
  After reading the Quick Start of Borg Backup they look very similar. But as far as I can tell, borg can be encrypted and compressed while restic is always. You can mounting your backups in restic to. It also seems that restic supports more repository locations such as several cloud storages and via a special http server.
  I also noticed that borg is mainly written in python while restic is written in go. That said I assume that restic is a bit faster based on the language (I have not tested that).
  
  It was a while ago that I compared them so this may have changed, but one of the main differences that I saw was that borg had to backup over ssh, while restic had a storage backend for many different storage methods and APIs.
  
  I haven't used either, much less benchmarked them, but the performance differences should be negligible due to the IO-bound nature of the work. Even with compression & encryption, it's likely that either the language is fast enough or that it's implemented in a fast language.
  Still, I wouldn't call the choice of language insignificant. IIRC, Go is strongly typed while Python isn't. Even if type errors are rare, I would rather trust software written to be immune to them. (Same with memory safety, but both languages use garbage collection, so it's not really relevant in this case.)
  Of course, I could be wrong. Maybe one of the tools cannot fully utilize the network or disk. Perhaps one of them uses multithreaded compression while the other doesn't. Architectual decisions made early on could also cause performance problems. I'd just rather not assume any noticeable performance differences caused by the programming language used in this case.
  Sorry for the rant, this ended up being a little longer than I expected.
  Also, Rust rewrite when? :P

I'm curious, is there a reason why noone uses deja-dup? I use it with an external SSD on Ubuntu and (receently) Mint, where it comes pre-installed, and did not encounter Problems.
- The restore process takes forever and sometimes fails. Last time I was forced to try every daily backup to several days before last backup to find one that could actually be restored. I have switched to borg (using Pika Backup for desktop and Borgmatic for servers). No restores have failed since.
  
  Thanks for your feedback, maybe I should look into switching
- What do you backup with dejadup? Everything under /home?
  
  Mostly, with some folders excepted (e.g. my Nextcloud folder)

I keep all of my documents on a local server so all that is on any of my computers is software. So if I need to reinstall Linux I cab just do it without wording about losing anything.

I recently switched to Kopia for my offsite backup solution.
It's apparently one of the faster options, and it can be set up so that the files of the differential backups are handled by a repository server on the offsite end, so file management doesn't need to happen over the network at a snails pace.
The result is a way to maintain frequent full backups of my nextcloud instance, with almost no downtime.
Nextcloud only goes into maintenance mode for the duration of a postgres database dump, after which the actual file system backup occurs using a temporary btrfs snapshot, containing a frozen filesystem at the time of the database dump.

for my server I use proxmox backup server to an external HDD for my containers, and I back up media monthly to an encrypted cold drive.
For my desktop? I use a mix of syncthing (which goes to the server) and windows file history(if I logged into the windows partition) and I want to get timeshift working I just have so much data that it's hard to manage so currently I'll just shed some tears if my Linux system fails

I use borg the same way you describe. Part of my nixos config builds a systemd unit that starts a backup on various directories on my machine at midnight every day. I have 2 repos: one to store locally and on a cloud backup provider (borgbase) and another thats just stored locally. That is, another computer in my house. That local only is for all my home media. I havent yet put the large dataset of photos and videos on the cloud or offsite.

There’s nothing saved on my system I couldn’t afford to lose. All my work stuff is saved in Google Drive for better or worse. I have a few small files in a personal Proton Drive that I backup manually. I wipe my own system a few times a year and I rarely ever save anything first. Honestly very refreshing to live your life like that. Other than my cat, pretty much all my possessions could disappear tomorrow and I’d get over it pretty quickly.

I currently use rclone with encryption to iDrive e2. I’m considering switching to Backrest, though.
I originally tried Backblaze b2, but exceeded their API quotas in their free tier and iDrive has “free” API calls, so I recently bought a year’s worth. I still have a 2 year Proton subscription and tried rclone with Proton drive, but it was too slow.

Nice try, mister ransonware attacker hacker!

Timeshift for snapshots and deja backups for files

My work flow is pretty similar to yours:
For my desktop and laptops: systemd timer and service that backups every 15 minutes using restic to my NAS.
For my NAS : daily backup using restic + ZFS snapshots.
All restic backups are then uploaded daily to Backblaze B2.
- Do you create ZFS snapshots and let those be backed up to B2 via restic or do you backup different types of data, one with ZFS snapshots and one with restic?
  
  Only restic snapshots are backed-up to B2. ZFS snapshots are for undoing mistakes, though I enabled them recently and I have yet to use them.

I recently bought a storagebox from Hatzner and set up my server to run borgmatic every day to backup to it.
I've also discovered that Pika Backup works really well as a "read only" graphical browser for borg repos.

Most of my data are on 2x16TB HDDs running an mdraid1 and then I backup it all to a usb drive with Borg Backup.
The os.qcow2 files live on my m.2 NVMe and are manually backuped to the mdraid1 before running the borg backup.
I should automate the borg backup but currently I just do it manually a few times a month.
Would also like to have two usb drives and keep one offline in another part of the house but that's another future project.