I'm consulting for a company that makes around €1 billion annual turnover. They don't make their own backups. They rely on disk copies made by the datacenter operator, which happen randomly, and which they don't test themselves.
Recently a user error caused the production database to be destroyed. The most recent "backup" was four days old. Then we had to replay all transactions that happened during those four days. It's insane.
But the most insane part was, nobody was shocked or terrified about the incident. "Business as usual" it seems.
"Oh there goes Super Entrepise DB Partner again" turns into a product next fiscal year, that shutdowns the following year because the scope was too big, but at least they tried to make things better.
A full OS installation may not change a lot, or change with security updates that anyway are stored elsewhere.
Configurations have their own lifecycle, actors, and good practices on how to keep and backup them. Same with code.
Data is what matters if you have saved somewhat everything else. And it could have a different treatment file tree backups from I.e. database backups.
Logs is something that frequently changes, but you can have a proper log server for which logs are data.
Things can be this granular, or go for storage backup. But the granularity, while may add complexity, may lower costs and increase how much of what matters you can store for longer periods of time.
* Is the file userland-compressed, filesystem-or-device-compressed, or uncompressed?
* What are you going to do about secret keys?
* Is the file immutable, replace-only (most files), append-only (not limited to logs; beware the need to defrag these), or fully mutable (rare - mostly databases or dangerous archive software)?
* Can you rely on page size for (some) chunking, or do you need to rely entirely on content-based chunking?
* How exactly are you going to garbage-collect the data from no-longer-active backups?
* Does your filesystem expose an accurate "this file changed" signal, or better an actual hash? Does it support chunk sharing? Do you know how those APIs work?
* Are you crossing a kernel version that is one-way incompatible?
* Do you have control of the raw filesystem at the other side? (e.g. the most efficient backup for btrfs is only possible with this)
In my opinion a good backup (system) is only good, if it has been tested to be restorable as fast as possible and the procedure is clear (like in documented).
How often have I heard or seen backups that "work great" and "oh, no problem we have them" only to see them fail or take ages to restore, when the disaster has happened (2 days can be an expensive amount of time in a production environment). Quite too often only parts could be restored.
Another missing aspect is within the snapshots section... I like restic, which provides repository based backup with deduplicated snapshots for FILES (not filesystems). It's pretty much what you want if you don't have ZFS (or other reliable snapshot based filesystems) to keep different versions of your files that have been deleted on the filesystem.
The last aspect is partly mentioned, the better PULL than PUSH part. Ransomware is really clever these days and if you PUSH your backups, it can also encrypt or delete all your backups, because it has access to everything... So you could either use readonly media (like Blurays) or PULL is mandatory. It is also helpful to have auto-snapshotting on ZFS via zfs-auto-snapshot, zrepl or sanoid to go back in time to where the ransomware has started its journey.
Or like someone already commented you can use a server that allows push but doesn't allow to mess with older files. You can for example restrict ssh to only the scp command and the ssh server can moreover offer a chroot'ed environment to which scp shall copy the backups. And the server can for example daily rotate that chroot.
The push can then push one thing: daily backups. It cannot log in. It cannot overwrite older backups.
Short of a serious SSH exploit where the ransomware could both re-configure the server to accept all ssh (and not just scp) and escape the chroot box, the ransomware is simply not destroying data from before the ransomware found its way on the system.
My backup procedure does that for the one backup server that I have on a dedicated server: a chroot'ed ssh server that only accepts scp and nothing else. It's of course just one part of the backup procedure, not the only thing I rely on for backups.
P.S: it's not incompatible with also using read-only media
On the face of it "append-only access (no changes)" seems sound to me
I did not see a likely reason in a quick review of their comment history.
You can view a comment directly by following the "... ago" link, and from there you can use the "vouch" link to revive the comment. I vouched for a few of TacticalCoder's recent comments.
That depends on how you have access to your backup servers configured. I'm comfortable with append-only backup enforcement for push backups[0] with Borg and Restic via SSH, although I do use offline backup drive rotation as a last line of defense for my local backup set. YMMV.
0 - https://marcusb.org/posts/2024/07/ransomware-resistant-backu...
Curious what you consider valuable data?
Edit: I should say for pictues I have around 2Tb right now (downside of being a hobby photographer)
I have a large amount of memories and "mathom" as well, in double copies, but I connect and add to this data so rarely that it absolutely does not have to be part of any ongoing backup plan.
My preferred solution is to let client only write new backups, never delete. The deletion is handled separately (manually or cron on the target).
You can do this with rsync/ssh via the allowed command feature in .ssh/authorized_keys.
pacman -S arch-install-scripts # Need this package (for debian you need debootstrap)
pacstrap -c /mnt/backups/TestSpawn base # Makes chroot
systemd-nspawn -D /mnt/backups/TestSpawn # Logs in
passwd # Set the root password. Do whatever else you need then exit
sudo ln -s /mnt/backups/TestSpawn /var/lib/machines/TestSpawn
sudo machinectl start TestSpawn # Congrats, you can now control with machinectl
Configs work like normal systemd stuff. So you can limit access controls, restrict file paths, make the service boot only at certain times or activate based on listening to a port, make only accessible via 192.168.1.0/24 (or 100.64.0.0/10), limit memory/CPU usage, or whatever you want. (I also like to use BTRFS subvolumes) You could also go systemd-vmspawn for a full VM if you really wanted to.Extra nice, you can use importctl to then replicate.
You might think this is unsuitable for your photo/music/etc. collection, but there's no technical reason you couldn't use the database as the primary storage mechanism. SQLite will take you to ~281 terabytes with a 64k page size. MSSQL supports something crazy like 500 petabytes. The blob data types will choke on your 8k avengers rip, but you could store it in 1 gig chunks - There are probably other benefits to this anyways.
I've been working on backup and disaster recovery software for 10 years. There's a common phrase in our realm that I feel obligated to share, given the nature of this article.
> "Friends don't let friends build their own Backup and Disaster Recovery (BCDR) solution"
Building BCDR is notoriously difficult and has many gotchas. The author hinted at some of them, but maybe let me try to drive some of them home.
- Backup is not disaster recovery: In case of a disaster, you want to be up and running near-instantly. If you cannot get back up and running in a few minutes/hours, your customers will lose your trust and your business will hurt. Being able to restore a system (file server, database, domain controller) with minimal data loss (<1 hr) is vital for the survival of many businesses. See Recovery Time Objective (RTO) and Recovery Point Objective (RPO).
- Point-in-time backups (crash consistent vs application consistent): A proper backup system should support point-in-time backups. An "rsync copy" of a file system is not a point-in-time backup (unless the system is offline), because the system changes constantly. A point-in-time backup is a backup in which each block/file/.. maps to the same exact timestamp. We typically differentiate between "crash consistent backups" which are similar to pulling the plug on a running computer, and "application consistent backups", which involves asking all important applications to persist their state to disk and freeze operations while the backup is happening. Application consistent backups (which is provided by Microsoft's VSS, as mentioned by the author) significantly reduce the chances of corruption. You should never trust an "rsync copy" or even crash consistent backups.
- Murphy's law is really true for storage media: My parents put their backups on external hard drives, and all of r/DataHoarder seems to buy only 12T HDDs and put them in a RAID0. In my experience, hard drives of all kinds fail all the time (though NVMe SSD > other SSD > HDD), so having backups in multiple places (3-2-1 backup!) is important.
(I have more stuff I wanted to write down, but it's late and the kids will be up early.)
What does this have to do with security? You shouldn't be backing up data in a way that's visible to the server. Use something like restic. Do not rely on the provider having good security.
Database dumps help with this, to a large extent, especially if the application itself is making the dumps at an appropriate time. But often you have to make the dump outside the application, meaning you could hit it in the middle of a sequence of queries.
Curious if anyone has useful tips for dealing with this.
But for the most part as especially in the cloud, this shouldn't be an issue.
rr808•3h ago
bambax•3h ago
xandrius•3h ago
For the phones and cameras, setup Nextcloud and have it automatically sync to your own home network. Then have a nightly backup to another disk with a health check after it finishes.
After that you can pick either a cloud host which your trust or get another drive of ours into someone else's server to have another locstion for your 2nd backup and you're golden.
sandreas•3h ago
I would also distinguish between documents (like PDF and TIFF) and photos - there is also paperless ngx.
setopt•2h ago
sandreas•2h ago
https://mobiussync.com/
baby_souffle•1h ago
bravesoul2•2h ago
palata•2h ago
rsolva•2h ago
nor-and-or-not•2h ago
bravesoul2•2h ago
For me one win/mac with backblaze. Dump everything to that machine. Second ext. Drive backup just in case.
haiku2077•1h ago
BirdieNZ•10m ago
You can also store photos/scans on desktops in the same NAS and make sure Immich is picking them up (and then the backup script will catch them if they get imported to Immich). For an HN user it's pretty straight-forward to set up.
Jedd•6m ago
As bambax noted, you do in fact need a backup system -- you just don't realise that yet.
And you want a way of sharing data between devices. Without knowing what you've explored, and constraints imposed by your vendors of choice, it's hard to be prescriptive.
FWIW I use syncthing on gnu/linux, microsoft windows, android, in a mesh arrangement, for several collections of stuff, anchored back to two dedicated archive targets (small memory / large storage debian VMs) running at two different sites, and then perform regular snapshots on those using borgbackup. This gives me backups and archives. My RPO is 24h but could easily be reduced to whatever figure I want.
I believe this method won't work if Apple phones / tablets are involved, as you are not allowed to run background tasks (for syncthing) on your devices.
(I have ~500GB of photos, and several 10-200GB collections of docs and miscellaneous files, as unique repositories - none of these experience massive changes, it's mostly incremental differences, so it is pretty frugal with diff-based backup systems.)