Jules Bean wrote: > As to where my superblock has gone, the only theory I have is that the > MD layer knew that my partitions were 400G large while the kernel was > convinced they were 250G large, so the md layer tried to write the > superblock at (approx) +400G, and the kernel refused to do that. I failed to do a similar grow operation recently and had to re-create. I was using 0.9 sb which is stored at the end of the disk. I have no idea how this is supposed to work... If I have sda1 at 250Mb then the sb is at 250-d Mb I'd like to stop the array, remove the partition, grow the partition to 400Mb and start the array. This won't work because md won't find an sb at 400-d Mb and so won't know that it's an md component. However, with a 1.1 or 1.2 sb I think it would work. I tried using Michael Tokarev's mdsuper to pull the sb from the partition, resize and then push it to the end of the new partition but that went wrong somewhere. I think the process should be: 1 stop array 2 mdadm --save-superblock=component.sb /dev/<component> 3 grow partition 4 mdadm --write-superblock=component.sb /dev/<component> 5 start array 6 grow array 7 grow fs For sb 1.1 and 1.2 steps 2+4 should be no-ops in step 4 mdadm may want to call the reread pt ioctl (which is what blockdev --rereadpt does) This approach, it seems to me, would avoid any reconstruction and would be a 'safer' way to grow the components. If this sounds reasonable then I'd happily have a go at implementing --save-superblock/--write-superblock David -- 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
