Feature added by: Bat Pul (batpul) Feature #313130, revision 1 Title: Support btrfs RAID1 mirrored partitions openFATE: Unconfirmed Priority Requester: Important Requested by: Bat Pul (batpul) Partner organization: openSUSE.org Description: In release 12.1 openSUSE adds support for btrfs. The btrfs filesystem supports several RAID configurations on the filesystem level. This is great since now it is no longer necessary to use Multiple Devices or other mechanisms to support RAID filesystems. Mirrored filesystems are a means to increase data reliability and read speed. However, btrfs mirrored filesystems are currently not supported during installation nor in yast2. Since it is not trivial to add such a filesystem to a openSUSE 12.1 system this is a useful addition. In addition there should be integrated support in openSUSE to detect and recover from situations where one partition fails which is part of a btrfs RAID1 filesystem. Use Case: It is far from trivial to accomplish integration of a RAID1 btrfs mirrored filesystem in the system. Such a filesystem can be created with: mkfs.btrfs -L mylabel -m raid1 -d raid1 /dev/sda4 /dev/sdb4 This filesystem can then be mounted with: mount /dev/sda4 /mnt However, after reboot openSUSE 12.1 fails to mount this again with the identical command. As a response it gives the following two unclear messages in dmesg: btrfs: failed to read the system array on sda4 btrfs: open_ctree failed The trick is to specify both devices as: mount -o device=/dev/sda4,device=/dev/sdb4 /dev/sda4 /mnt The fstab entry should then become: /dev/sda4 /mnt btrfs device=/dev/sda4,device=/dev/sdb4 1 2 Then after reboot the filesystem is mounted. Knowledge of these facts and integration of btrfs RAID options during installation and in yast2 would help. -- openSUSE Feature: https://features.opensuse.org/313130