How to clone a USB flash drive using dd?

Solution 1:

You copied the partition, but not the MBR. Copy the first 446 bytes of the device itself.

Solution 2:

I recently had to clone a 32gb trancend thumbdrive onto another. My drive is a multiboot with additional software so I didn't want to just copy all files on the FS. DD was a clear choice, but I was on windows.

I had cygwin installed and did the following.

first I had to figure out what /dev/sdX device my f: volume was. To do so run this command in cygwin. (TIP: Make sure you start cygwin with admin privs.. *Right click on cygwin and "Run as Administrator")

cat /proc/partitions

which should output:

   8 0 3813383838 sda
   8 1       4031 sda3 C:\
   8 15  30588303 sdb 
   8 15  30588303 sdb1 E:\
   8 21  30530020 sdc
   8 22  30530020 sdc1 F:\

etc... Here you can clearly see for me to clone my F: drive to my E: drive I'd issue the following command.

dd if=/dev/sdc of=/dev/sdb bs=8M

My image was 32gb.. and I didn't want to just sit and wait with a blinking cursor.. I wanted to see progress so I installed "pv" in cygwin.

dd if=/dev/sdc | pv | dd of=/dev/sdb bs=8M

Hope this helps