> On 09/03/2017 02:59 PM, Eben King wrote:
>> I have a RAID-1 setup (2x1 TB) that I use for media storage. I want to
>> migrate to a new(er) set of disks....
>> One disk was copied successfully, at
>> least about 2/3 of it. Then something crapped out and I had to resume.
>> Assuming I got if= and of= correct in dd, the rest should be copied
>> successfully too. The other, I know I screwed up on.
>> So, what's the way that puts the least stress on the drives to expand the
>> RAID from one disk to two? Also, what's a more, er, "user-tolerant" way
>> to duplicate disks that can be resumed?
On 09/03/17 15:47, William A. B. Maloney wrote:
> This is not a definitive answer, to be sure, but I would look at *rsync* to
> do the data-copying. If you're starting with a blank target disk, it will
> copy everything over. If, however, you're starting with a disk that has part
> of the data already in place, it will ignore files that are identical on the
> source and target, update those on the target that are older, and add any
> from the source that are not on the target at all.
> I don't know of a down-side to *rsync*, but maybe more experienced users
> will offer more input.
RAID disks don't have a normal partition map:
eben@pc:~$ sudo fdisk -l /dev/sdk
Disk /dev/sdk: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 4096 bytes / 33553920 bytes
Disklabel type: dos
Disk identifier: 0x466ffdd2
Device Boot Start End Sectors Size Id Type
/dev/sdk1 2048 1953520000 1953517953 931.5G da Non-FS data
eben@pc:~$ sudo dd if=/dev/sdk bs=512 skip=2048 | file -
/dev/stdin: Linux Software RAID version 1.2 (1)
UUID=4dfe9043:8416bab7:621093d8:bf7aa8c2 name=pc:0 level=1 disks=2
I can see how this would work if I set up the destination RAID and then
populate it using rsync. If I want to duplicate the source RAID's component
disks, can it resume if interrupted?
-eben [log in to unmask]
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