On 07/03/2013 12:15 PM, Vasiliy Tolstov wrote: > 2013/7/3 Jason Warr <jason@xxxxxxxx>: >> If you want md0 to be a raid1 device in the future you need to create it >> as a 2 device array with a missing drive: >> >> mdadm -C /dev/md0 -l1 -n2 /dev/sda missing >> >> You can then add in the other device whenever you can/want. The key >> though would be to make sure the size in blocks of the first device is = >> or smaller than the second device will be. What I would do is create a >> fd type partition that is 1% smaller than total raw device size on >> /dev/sda just to give your self a small margin of error. >> >> parted /dev/sda mkpart primary 1.0 99% --align optimal >> parted /dev/sda set 1 raid on >> mdadm -C /dev/md0 -l1 -n2 /dev/sda1 missing >> >> That way down the road you can add in a disk of about the same size to >> the existing raid1 completely transparent of bcache with a single command. >> >> mdadm /dev/md1 -a /dev/sdX1 > > Thanks. But as i understand if the second drive bigger then first i > can sync raid1 and after thet grow /dev/md0 to new size... In a mirror your raid device can only be as big as the smallest device. So if you put in a secondary device that is larger than the first you still cannot go beyond the size of the first unless you then replace it after syncing the second. > -- > Vasiliy Tolstov, > e-mail: v.tolstov@xxxxxxxxx > jabber: vase@xxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-bcache" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
