Hello Theo,

T> $ sudo dd if=/dev/rdisk3 of=your-image.img bs=1m

At the Pi 3B+ this gives the error:
dd: invalid number '1m'

Use 1M instead of 1m  ;-).
I am now writing Raspbian Stretch 2018-06-27 img from a DownLoad dir
on a 32 GB usb card which is /dev/sda to another 32 GB card as /dev/sdb.
The 16 GB SDcard booted from had too little free space as temporary storage.
About 10 minutes I know the result ;-).

sudo dd if=/media/pi/rootfs/home/pi/Downloads/Raspbian/2018-06-27-raspbian-
stretch.img of=/dev/sdb bs=1M
4600+0 records in
4600+0 records out
4823449600 bytes (4.8 GB) copied, 567.882 s, 8.5 MB
He's ready and it works well. Ofcourse many things need configuration.

Henri.

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