Rebuild raid from other system

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Brief description of the problem

Hello, has rockstor a way to rebuild an array from raid5 coming from another linux system? my motherboard get HW fault, and my 5 disks remain there. I’m building a new machine with all these 5 disks and thinking to use Rockstor if has a easy way to rebuild the array…(with or without using code)

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@Tipotimido welcome to the Rockstor community. The RAID5 on your other system is that based on btrfs? Or other fs formats, hardware vs. software RAID?

If it is btrfs, you might be able to just import that RAID into a Rockstor instance and then execute any needed RAID repairs (if any). If not, then Rockstor itself won’t be of much help.

With that additional information @phillxnet might be able to give further recommendations if necessary.

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@Tipotimido welcome to the world of Rockstor.

As @Hooverdan has already said, if your disks are btrfs formatted from a non-Rockstor system then this may be possible. Some more info re the RAID system used (hardware or software) and filesystem will help. I bow to @phillxnet greater knowledge around this.

However, be aware that btrfs Raid5/6 is not recommended for prod use as it has some potential shortcomings apparently. I’d search the internet for more detailed information on this though.

Easiest case is that you could mount the drives in a Rockstor system, format them, and then restore form your backup assuming you have one.

Before jumping into anything, let us know the current failed system, fs, etc first.


Thank you guys.
i’ll try to give you all info i can:

  • Raid is a Linux RAID 6 (not 5 sorry for mistake)
  • HDDs format are EXT4
  • i’m pretty sure is an HW raid becouse the machine with faulty motherboard was a Lacie 5Big N2
  • dont know nothing about btrfs…
  • nope, i have no backup, only these 5 disks.
  • I know that with mdadm --assemble /dev/xxx command is possible to re-assemble the raid in a linux system… but it will be the first time for me, i prefer something with GUI or UX with buttons and suggetions :grin:

@Tipotimido Rockstor is focused only on the btrfs, so it doesn’t have any tools/options for EXT4 RAIDs (hardware or software RAIDs). Sorry, I think you will have to look elsewhere to see whether you can re-assemble that RAID. Not sure whether webmin would be close enough, otherwise you probably have to deal with mdadm in the CLI.
I think, if it was a HW raid, then it seems that you need a new system with the same type of controller, but I am certainly not the expert on that.


…oh, ok i’ve understand, thanks for the clarifications.

I have to concur with @Hooverdan here. Unfortunately my expertise in that area is minimal/zero I’m afraid. You may need to do some further internet research on the topic in hand.

I sincerely hope you are able to fix the situation and recover your data. It might also be worth considering a backup going forward - they are there for just these types of scenarios.

Good luck.


If you are lucky enough for this to have been a linux md raid, this is usually quite trivial.
Install a bare opensuse leap 15.4 without your raid connected, aka just on a local drive.
connect your raid drives.
run: sudo mdadm --assemble --scan

This should now find your md raid as md0

check it via: sudo mdadm --detail /dev/md0

If looks healthy, mount it similar to: sudo mount /dev/md0 /mnt/md0test (make sure you pre-create the /mnt/md0test directory)

test your data

Then backup all your data, make sure you have it backed up. then back it up somewhere else again to be triple sure.

Install rockstor to replace the suse leap 15.4, follow steps to upgrade to the newer kernel to get btrfs raid5.
kill those previous mdraid drives, and setup as btrfs raid5/6
restore your data.



Wise words, he speaks.