Hello, when I run: mdadm /dev/md1 --grow --raid-devices 16 --backup-file=/md1backup I get: mdadm: Need to backup 1792K of critical section.. mdadm: Cannot set device size/shape for /dev/md1: Invalid argument Any help? Iain - 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