this post was submitted on 21 Feb 2024
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I recently decided to replace the SD card in my Raspberry Pi and reinstall the system. Without any special backups in place, I turned to rsync to duplicate /var/lib/docker with all my containers, including Nextcloud.

Step #1: I mounted an external hard drive to /mnt/temp.

Step #2: I used rsync to copy the data to /mnt/tmp. See the difference?

Step #3: I reformatted the SD card.

Step #4: I realized my mistake.

Moral: no one is immune to their own stupidity πŸ˜‚

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[–] [email protected] 84 points 6 months ago (2 children)

If you have one backup, you have no backup. That's a hard lesson to learn, but if you care about those photos it's possible to recover them if you haven't written stuff on that sdcard yet.

[–] [email protected] 35 points 6 months ago (1 children)

At least 3 backups, 2 different media, 1 offsite location.

[–] [email protected] 8 points 6 months ago* (last edited 6 months ago)

I like 3-2-1-1-0 better. Like yours, but:

  • the additional 1 is for "offline" (so you have one offsite and offline backup copy).
  • 0 for zero errors. Backups must be tested and verified.
[–] [email protected] 6 points 6 months ago

Also, if you haven't tried to restore from backup, you have no backup.

[–] [email protected] 43 points 6 months ago* (last edited 6 months ago) (11 children)

Fuck up #1: no backups

Fuck up #2: using SD cards for data storage. SD cards and USB drives are ephemeral storage devices, not to be relied on. Most of the time they use file systems like FAT32 which are far less safe than NTFS or ext4. Use reliable storage media, like hard drives.

Fuck up #3: no backups.

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[–] [email protected] 29 points 6 months ago (1 children)

Unless you’ve used something secure for formatting or wrote data to the SD after, consider attempting data recovery.

[–] [email protected] 11 points 6 months ago (1 children)

No luck with extundelete (segfault) and testdisk (sees some deleted files, but not /var/lib/docker). At least I can always throws it away and not worry about safety of my data! :)

[–] [email protected] 16 points 6 months ago (1 children)

You can always try professional data recovery services. It just depends on how much the data is worth to you.

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[–] [email protected] 28 points 6 months ago* (last edited 6 months ago) (1 children)

I'm just impressed an SD card in a Pi lasted since 2017 without losing all your data on its own.

For the future the general guideline is 3 copies of your data at minimum, so definitely set up some backups.

[–] [email protected] 2 points 6 months ago (1 children)

How do you actually do that?

[–] [email protected] 2 points 6 months ago

Lots of backup software out there, I use a mix of Veeam Endpoint, Restic w/ Backblaze B2, and iDrive.

[–] [email protected] 23 points 6 months ago* (last edited 6 months ago) (1 children)

If you haven't done much writing to the SD card, you may be able to recover the data. Data isn't really "deleted", it is just labeled as deleted. There is software that can comb through the raw data and try to make sense of what files were there. I don't know of any specific software, so if anyone knows, please reply

Edit: Another commenter mentioned some success with DMDE

Edit 2: Worth mentioning that this is true of formats. As long as it doesn't zero out the entire media, it just edits the file system metadata to say there are no files.

[–] [email protected] 11 points 6 months ago

PhotoRec and TestDisk are probably the best, but they don't recover file structure.

[–] [email protected] 21 points 6 months ago (1 children)

There's an old saying, "Unix is user friendly, it's just fussy about it's friends."

[–] [email protected] 7 points 6 months ago

Unix is the kind of friend who won't bat an eye about holding your beer while you go and do something incredibly stupid

[–] [email protected] 20 points 6 months ago

Everyone else is gonna be like "if you don't have at least 3 backups of something blahblah" but you know, not everyone has the finances for that, so advice from a cheapskate computer nerd: when going through critical transfers/reformats/deletions like you were doing, ALWAYS try actually recovering stuff from the backup before you cross the point of no return. E.g. if the backup is a .zip, extract a few individual files from it and open them in their respective programs.

[–] [email protected] 19 points 6 months ago* (last edited 6 months ago)

Testdisk and photorec, use them, they even saved my data from bricked Chinese usb flash drive, so it'll save yours unless you wrote dd if /dev/zero of /*/microsd. Also here's the tip, don't attempt to rebuild partition firstly, first step try to copy all files from microsd to another device with these programs and after that try other ways, edit: I've seen from your other comments that your data already was overwritten, my condolences

[–] [email protected] 15 points 6 months ago

Condolences

[–] [email protected] 13 points 6 months ago (4 children)

I know I'm going to get down voted for this but this would be almost impossible to fuck up with a gui. Yet people insist that writing commands manually is superior. I'm sorry for your loss.

[–] [email protected] 6 points 6 months ago (1 children)

Guardrails are absolutely not a reason why people prefer the CLI. We want the guardrails off so we can go faster.

[–] [email protected] 3 points 6 months ago (1 children)

This is on me for sure that I've never seen anyone be faster using a CLI compared to a GUI especially for basic operations which is what most of us do 95% of the time. I know there are specific cases where a command just does it better/easier but for me that's not the case for everyday stuff.

[–] [email protected] 3 points 6 months ago* (last edited 6 months ago)

But what about the movies where the actors are typing commands and a visual GUI is moving around and updating on the screen (and making sound effects too).

Isn't that the best of all worlds? /s

[–] [email protected] 6 points 6 months ago* (last edited 6 months ago)

Fair enough.

CLI is not about ease to begin with, it is about versatility.

[–] [email protected] 5 points 6 months ago (1 children)

There is something to be said about CLI applications being risky by default ("rm" doesn't prompt to ask, rsync --delete will do just that). But I've definitely slipped on the mouse button while "drag & dropping" files in a GUI before. And it can be a right mess if you move a bunch of individual files rather than a sub-folder...

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[–] [email protected] 11 points 6 months ago* (last edited 6 months ago) (6 children)

Sorry to hear, I feel you:

I wanted to delete all .m3u-files in my music collection when I learned:

find ./ -name "*.m3u" -delete -> this would have been the right way, all .m3u in the current folder would have been deleted.

find ./ -delete -name "*.m3u" -> WRONG, this just deletes the current folder and everything in it.

Who would have known, that the position of -delete actually matters.

[–] [email protected] 6 points 6 months ago (2 children)

I didn't know there was a -delete option to find! I've been piping to xargs -0 for decades!

[–] [email protected] 5 points 6 months ago

Probably because it's easier to fuck up. With piping to xargs, you are forced to put the delete command last.

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[–] [email protected] 5 points 6 months ago

I did this sort of mistakes too, luckily BTRFS snapshots are always here to save the day !

[–] [email protected] 2 points 6 months ago* (last edited 6 months ago)

fd -tf -e m3u -x rm loads all cores and nothing works faster

[–] [email protected] 2 points 6 months ago

I use GNU find every day and still have to google about the details. Only learnt about - delete the other day, good to know the position matters.

[–] [email protected] 2 points 6 months ago

I can recommend fd to everyone frustrated with find, it has a much more intuitive interface imo, and it's also significantly faster.

[–] [email protected] 2 points 6 months ago (1 children)

The first one would have deleted nothing as it needs to match the whole name. I recommend running find with an explicit -print before replacing it in place with -delete or -exec. It's good to remember that find has a complex order dependent language with -or and -and, but not maybe the best idea to try to use those features.

[–] [email protected] 3 points 6 months ago

Lemmy interpreted the * as something cursive. I try to edit it like I mean it.

[–] [email protected] 7 points 6 months ago (1 children)

Unlesa you did a full zeroing format the info might still be available. There was an applicarion that attempts to rebuild the partition / Filesystem from left over meta data or inode info. I forget the name unfortunately. Normall the strings command will get your photos but probably not if they were in a docker image database.

[–] [email protected] 9 points 6 months ago (1 children)

Testdisk and photorec? It's saved me heaps of times.

[–] [email protected] 3 points 6 months ago

Those are good for sure. And maybe it was testdisk. There was one that just undeleted the partition table delete. as long as new data had not been written everthing would be intact

[–] [email protected] 6 points 6 months ago

The bells of the Gion monastery in India echo with the warning that all things are impermanent.

[–] [email protected] 6 points 6 months ago (1 children)

My condolences :'(

I once lost a bunch of data because I accidently left a / at the end of a path... rsync can be dangerous lol

[–] [email protected] 2 points 6 months ago (1 children)

Rclone is superior IMHO, you have to explicitly name the output folder. Used to think it was a hassle but in hindsight being explicit about the destination reduces mistakes.

[–] [email protected] 2 points 5 months ago

Sometimes you're hands are tied by the tools already on the server - but I'll try to remember to check to see if that's available next time.

[–] [email protected] 5 points 6 months ago (1 children)

Sorry to read that.

I've dded an external drive instead of an SD card once by mistake. I've never felt more stupid than that day.

[–] [email protected] 3 points 6 months ago

Classic Disk Destroyer moment.

[–] [email protected] 4 points 6 months ago (1 children)

I think everyone has done this. I know I have. I believe I used dmda to recover all my photos back. Unfortunately I lost all the metadata for about 3000 photos. It took years to manually retap and redate them all but at least I didn’t lose them forever

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[–] [email protected] 3 points 6 months ago

Oh man, even reading that hurt ':D I'm sorry for your loss.

[–] [email protected] 2 points 6 months ago* (last edited 6 months ago)

Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I've seen in this thread:

Fewer Letters More Letters
RAID Redundant Array of Independent Disks for mass storage
SSD Solid State Drive mass storage
ZFS Solaris/Linux filesystem focusing on data integrity

3 acronyms in this thread; the most compressed thread commented on today has 7 acronyms.

[Thread #537 for this sub, first seen 23rd Feb 2024, 01:55] [FAQ] [Full list] [Contact] [Source code]

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