> Looking at the manual for that system, the drives are hot-swappable - even > with the onboard controller, but I am not sure if the linux software raid > supports hotswap. I guess you will have to test it. > > Linux software raid cannot due to partitioning issues or rather its support of partitions for raid devices. The disk might have to be first partitioned before it can be added to the array whereas hardware raid cards use the whole disk and do not have to worry about partitioning and therefore can make use of the disk immediately without any squabbles.