2014-03-12 6:12 GMT-03:00 David Brown [off-list ref]:
...

If you want to safely replace the disks in a raid5 array, the easiest
way is to add a new disk (this can be an external USB disk if necessary)
and re-shape to an asymmetric raid6 with parity Q on the new disk.  Now
you have an extra redundancy for safety.  (Use asymmetric raid6 to avoid
re-striping the existing disks.)

Is there a solution for other RAID setups? 1,0,6,10?

thanks