Dear list, I would like to swap out a drive in a RAID6 (4 drives), but ideally without letting the RAID degrade. I was thinking that it should be possible to declare the new disk a copy of the old one, let it sync, then remove the old one and let the new one take over, but MD does not seem to support that. Next, I thought that I could add the new disk as a spare, grow the array to 5 disks, and somehow shrink it back to 4 again, but of course that does not work either, since 4→5 is a reshape, and there seems to be no way to control which disk to remove from the RAID6 on a shrink (making it a spare), without degrading the array in the process. Does anyone have any ideas? This should not be so hard… -- martin | http://madduck.net/ | http://two.sentenc.es/ "courage is not the absence of fear, but the decision that something else is more important than fear." -- ambrose redmoon spamtraps: madduck.bogus@madduck.net