On 12/26/2017 02:40 PM, Sverd Johnsen wrote: > hey what happens when i format on a linear md. when one disk dies will > it still work in degraded state? assuming the disk that holds the > header is still there. i was thinking about doing something like this > to do btrfs raid over multiple disks via a single cryptsetup device If you map JBOD array (or in other words linear mapping) using MD or LVM2, and the device is activated in degraded mode (IOW some part of device is missing and is replaced with some fillings - in LVM usually by error targer), then it should still work. IOW if there is still a LUKS header, cryptsetup will unlock it, map it over degraded mapping and let you access it. Of course the missing part IO access will produce IO errors, but the rest of device should be accessible. You can easily try it with LVM2 - create LV over several disks, force remove one disk and partially activate that LV - LUKS over it should open fine if the header is still intact. But for btrfs I would better use its internal device mapping tan combine it with another volume tool. Milan _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx http://www.saout.de/mailman/listinfo/dm-crypt
