Re: [gentoo-user] backup horror story (happy ending)

[Philip Webb <purslow@ca.inter.net>]

241109 ralfconn wrote:
> I have a 4Tb hard disk half full of videos and photos my daughter took 
> with her cell phone over the years, shared with Win11 in a dual boot box 
> so it is NTFS-formatted. The disk is backed up on a different EXT4 disk 
> and the backup is performed by (ana)cron via an rsync bash script.
> 
> Last evening there was a power outage. When I rebooted in linux the NTFS 
> disk would not mount. OK, just e2fsck the disk and it will fix it, I 
> thought, forgetting that it was an NTFS not EXT. e2fsck -y starts 
> finding and fixing hundreds of issues on the disk, till I get bored, I 
> stop it and reboot into Win11, which chkdsk's it and mounts with no 
> problem in less than 10s.
> 
> Finally I realize the huge mistake I had made, allowing e2fsck to delete 
> thousands of otherwise fine clusters/nodes/whatever on a filesystem it 
> does not understand.
> 
> But I have a backup, no problem... till I realize the cron job had 
> already run so it had overwritten the old files with the new, corrupt 
> versions.
> 
> Fortunately rsync uses the file access date to quickly find potential 
> differences and since the e2fsck did not touch those the backup was 
> still fine.
> 
> Later I found that the disk did not mount in linux due to mount not 
> finding anymore the NTFS's UUID that I had in fstab, but it did mount 
> fine with /dev/sdx.

Lesson 1 : always have multiple back-ups on differenct devices,
incl  >= 1  off-site, eg USB stick in your bank safe-deposit box.
Lesson 2 : don't store anything important in Windows format.

It's good & lucky you escaped unscathed this time (smile).

-- 
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