How to clone micro SD card

Question

I need to clone micro SD card, using Windows or Linux OS. SD card should be cloned as a whole volume, and not as partition. It may contains several partitions, some of them cannot be recognized by Windows/Linux. Basically, I want to make SD card image file, and then to insert another SD card media and copy this file to it, overriding everything that this media contains. How can I do this?

Solution 1

On Linux you can use dd to do that.

dd if=/dev/sdcard1 of=/dev/sdcard2 where if is the origin and of the destination SDs.

or if you want to take the image first and copy it to 2nd SD after:

dd if=/dev/sdcard1 of=~/sdimage 
dd if=~/sdimage of=/dev/sdcard2

Solution 2

You could use Clonezilla, which is a small Linux live distro which allows you to create drive images or to exactly copy one drive to another.

Solution 3

Just use dd for Windows (http://www.chrysocome.net/dd).

Run CDM as Administrator:

dd --list

Check which device is your SD card. In my case it was: \\?\Device\Harddisk1\Partition0. Partition0 refers to the whole disk, Partition1 to the first partition, etc.

Copy whole SD card to an image file:

dd if=\\?\Device\Harddisk1\Partition0 of=my.img bs=1M --progress

Then insert the new card and write back image file to it:

dd if=my.img of=\\?\Device\Harddisk1\Partition0 bs=1M --progress

If you get an access denied error after writing couple of blocks, clean the partition table of the SD card before writing to it:

diskpart

DISKPART> list volume
DISKPART> select volume #
DISKPART> clean
DISKPART> exit

Comments

[Alex F]

Thanks. This is exactly what I am trying to do, but from some reason the second stage (image file to SD card) hangs after some time.

[Alex F]

Thanks. Can this program clone the whole media, and not only partition? Is this program free?

[laurent]

Are the SDs the same size? if not, the 2nd needs to be larger than 1st one. If not and SD1 not 100% used, you can try resizing the filesystems and partitions there but that is another topic :)

[Alex F]

Finally I managed to do this with dd, but it is necessary to unmount all SD card partitions before running dd.

[Sawtaytoes]

How have you used it? What are the steps to copy write an image to an SD card?