Transform TOS NAS to RAID NAS


i have just bought a parts for my Turis NAS, but only with one hard drive at the moment, that has been formated by Foris automatically to BTRFS. Will there be a way to transform it with full of data to a RAID system after buying another disk without reformatting and losing data?

Should be possible according to:

tx for the feedback, but I guess it assumes you have RAID0 but I think I do not have any RAID, or dos Foris automatically create one? How can I check if there is really one or not?

So what is the solution if I do not have any RAID?
And why does Foris not offer the option to create one?

It‘s possible, I did this on my homeserver

/dev/sdc1: new partition
/mnt: mountpoint off array

# Add new partition to disk array, this will result in a JBOD configuration
btrfs device add /dev/sdc1 /mnt

# Convert to RAID1
btrfs balance start -dconvert=raid1 -mconvert=raid1 /mnt

# See status of Conversion
btrfs balance status /mnt

BUT read about btrfs raid if you want to avoid data loss! Btrfs Raid1 is safe to use, but it behaves diffrently compared to old madm setups and kernel 4.4 has some known bugs related to btrfs raid! Especially make sure you know how to recover from failure! e.g. DO NOT mount a degraded Raid1 btrfs partition with kernel 4.4 as it lets you mount it only one time in rw mode!

See btrfs man page for example:


I guess you understood a new physical disk under “partition”, right? Since I cannot create new partition on the current 1 disk, since Foris formatted the whole disk to btrfs.

I have never used and created raid yet not wtih even mdadm, but if I understood you correctly, this works pretty neat way. So it also means, that btrfs does not need any prerequeisite for a special partition (like lvm), it can handle everything on its own.

A new partition on a new physical disk, yes :smiley:

Yes that‘s right. Btrfs is very powerful in handling raid. You can do many things dynamically and on a mounted filesystem. :slight_smile: Again, with great power comes great responsibility :smile:

Indeed. Just FYI, I have just been talking to btrfs devs, since many heard about btrfs reliability problems most for RAID5/6, and it seems most of them have been fixed and there is only one last lingering, that is also addressed partially:

They just udated a page here from the left to the right side, after my questions: :slight_smile:
And here is a status page:

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