That's probably a good idea. Hope you get most of it out of there. And find a way to backup when you're done ;) Vennlig hilsen roy -- Roy Sigurd Karlsbakk (+47) 98013356 http://blogg.karlsbakk.net/ GPG Public key: http://karlsbakk.net/roysigurdkarlsbakk.pubkey.txt -- Hið góða skaltu í stein höggva, hið illa í snjó rita. ----- Original Message ----- > From: "Jorge Nunes" <jorgebnunes@xxxxxxxxx> > To: "Roy Sigurd Karlsbakk" <roy@xxxxxxxxxxxxx> > Cc: "Linux Raid" <linux-raid@xxxxxxxxxxxxxxx> > Sent: Tuesday, 5 April, 2022 12:50:20 > Subject: Re: RAID 1 to RAID 5 failure > Hi roy. > > Thank you for your time. > > Now, I'm doing a photorec on /dev/sda and /dev/sdd and I get better > results on (some) of the data recovered if I do it on top of /dev/md0. > I don't care anymore about recovering the filesystem, I just want to > maximize the quality of data recovered with photorec. > > Best regards, > Jorge > > Roy Sigurd Karlsbakk <roy@xxxxxxxxxxxxx> escreveu no dia terça, > 5/04/2022 à(s) 10:17: >> >> I re-did these tests this morning, since I was unsure if I could have made some >> mistake last night - I was tired. There results were about the same - complete >> data loss. >> >> As for curiousity, I also tried to skip the expand phase after creating the >> initial raid5 on top of the raid1. After creating it, I stopped it and >> recreated the old raid1 with --assume-clean. This worked well - no errors from >> mount or fsck. >> >> So I guess it was the mdadm --grow --raid-devices=4 that was the final nail in >> the coffin. >> >> I just hope you find a way to backup your files next time. I'm quite sure we've >> all been there - thought we were smart enough or something and the shit hit the >> fan and no - we weren't. >> >> Vennlig hilsen >> >> roy >> -- >> Roy Sigurd Karlsbakk >> (+47) 98013356 >> http://blogg.karlsbakk.net/ >> GPG Public key: http://karlsbakk.net/roysigurdkarlsbakk.pubkey.txt >> -- >> Hið góða skaltu í stein höggva, hið illa í snjó rita. >> >> ----- Original Message ----- >> > From: "Roy Sigurd Karlsbakk" <roy@xxxxxxxxxxxxx> >> > To: "Jorge Nunes" <jorgebnunes@xxxxxxxxx> >> > Cc: "Linux Raid" <linux-raid@xxxxxxxxxxxxxxx> >> > Sent: Tuesday, 5 April, 2022 02:29:03 >> > Subject: Re: RAID 1 to RAID 5 failure >> >> >> Didn't do a backup :-( >> > >> > First mistake… *Always* keep a backup (or three) >> > >> >> >> >> Unmount everything: >> > >> > No need - what you should have done, was just to grow the array by >> > >> > Partition the new drives exactly like the old ones >> > mdadm --add /dev/md0 /dev/sd[cd]1 # note that sd[cd] means sdc and sdd, but can >> > be written this way on the commandline >> > mdadm --grow --level=5 --raid-devices=4 >> > >> > This would have grown and converted the array to raid5 without any data loss. >> > >> >> $ sudo mdadm --create /dev/md0 -a yes -l 5 -n 2 /dev/sda /dev/sdd >> > >> > As earlier mentioned, this is to create a new array, not a conversion. >> > >> >> So, my question is: Is there a chance to redo the array correctly >> >> without losing the information inside? Is it possible to recover the >> >> 'lost' partition that existed on RAID 1 to be able to do a convenient >> >> backup? Or the only chance is to have a correct disk alignment inside >> >> the array to be able to use photorec to recover the files correctly? >> > >> > As mentioned, it doesn't look promising, but there are a few things that can be >> > tried. >> > >> > Your data may still reside on the sda1 and sdd1, but since it was converted to >> > RAID-5, the data would have been distributed among the two drives and not being >> > the same on both. Further growing the raid, would move the data around to the >> > other disks. I did a small test here on some vdisks to see if this could be >> > reversed somehow and see if I could find the original filesystem. I could - but >> > it was terribly corrupted, so not a single file remained. >> > >> > If this was valuable data, there might be a way to rescue them, but I fear a lot >> > is overwritten already. Others in here (or other places) may know more about >> > how to fix this, though. If you find out how, please tell. It'd be interesting >> > to learn :) >> > >> > PS: I have my personal notebook for technical stuff at >> > https://wiki.karlsbakk.net/index.php/Roy's_notes in case you might find that >> > interesting. There's quite a bit about storage there. Simply growing a raid is >> > apparently forgotten, since I thought that was too simple. I'll add it. >> > >> > So hope you didn't lose too much valuable data >> > >> > Vennlig hilsen / Best regards >> > >> > roy >> > -- >> > Roy Sigurd Karlsbakk >> > (+47) 98013356 >> > -- >> > I all pedagogikk er det essensielt at pensum presenteres intelligibelt. Det er >> > et elementært imperativ for alle pedagoger å unngå eksessiv anvendelse av >> > idiomer med xenotyp etymologi. I de fleste tilfeller eksisterer adekvate og > > > relevante synonymer på norsk.
