Recover raid 5

[xv0]

I have a raid 5 with 3 bad devices, I have created an image with ddrescue and now I am trying to reassemble the raid through this manual.

https://raid.wiki.kernel.org/index.php/RAID_Recovery

Reading the last paragraph, I have the same problem.

If upon running the above with the --size parameter you get, as one of the authors of this page did, an error such as: "mdadm: /dev/sdb1 is smaller than given size. xxxK < yyyK + metadata", you may have stumbled upon a problem where the array was initially created with an earlier version of mdadm that reserved less device space. The solution seems to be to find an earlier version of mdadm to run with the creation command above (in this author's case, mdadm from Debian "squeeze" worked while mdadm from Debian "wheezy" refused to recreate the array of the required size).

My system is, the last release of Proxmox

Linux pve 5.15.74-1-pve #1 SMP PVE 5.15.74-1 (Mon, 14 Nov 2022 20:17:15 +0100) x86_64 GNU/Linux

With mdadm version v4.1 - 2018-10-01 when trying to recreate the raid with this command:

mdadm --create --assume-clean --level=5 --raid-devices=4 --size=1948662656 /dev/md7 /dev/loop2 missing /dev/loop1 /dev/loop0

I get the following output as per the manual:

mdadm: /dev/loop0 is smaller than given size. 1948661760K < 1948662272K + metadata
mdadm: /dev/loop1 is smaller than given size. 1948661760K < 1948662272K + metadata
mdadm: /dev/loop2 is smaller than given size. 1948661760K < 1948662272K + metadata

It gives me to understand that the raid was built with an older version of mdadm, therefore I would have to use an older version like v3.4 for example, but when trying to do a search with apt for the mdadm package, only the available version appears v4.1

# apt list -a mdadm
Listing... Done
mdadm/stable 4.1-11 amd64

So my question is if I can install an old version of mdadm on this version of proxmox with that kernel, to try to raise the raid, do I have to use another repository?

Thanks.

 

[floh8]

Do u really need the size-param? Are u sure its he right number?