Hi The day before I grew a 4 times 300GB disk RAID5. I replaced the 300GB drives by 750GB ones. As far as I can see the proposed way to do that is to kick a drive from RAID and let a spare drive take over - for sensible data this is scary - at least for me, because I lose redundancy for the whole time of rebuild. Everything worked fine - so no harm is done - but is there a way to replace a disk without losing redundancy? Is it possible to mark a disk as "to be replaced by an existing spare", then migrate to the spare disk and kick the old disk _after_ migration has been done? Or not even kick - but mark as new spare. This feature would be even more interesting for partially degraded arrays with read problems on different disks which do not apply to the same RAID chunk (up to now I've seen one array in such a state and this one was able to recover by automatically rewriting the unreadable sectors). The point is - I would have felt better if I had been able to mark the old disks read only and migrate disk by disk without losing the partially damaged redundancy. Best Regards Ralf Mueller -- Van Roy's Law: ------------------------------------------------------- An unbreakable toy is useful for breaking other toys. - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html