PiClone

Setup

Main sd card with another on an extension cable and card reader.

Links

https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=35668&p=301919#p301919

http://www.johnaldred.com/moving-linux-to-smaller-sd-cards/

https://github.com/billw2/rpi-clone

https://www.raspberrypi.org/forums/viewtopic.php?f=29&t=13028

Then

sudo fdisk -l 

did show the disk

Device         Boot  Start      End  Sectors  Size Id Type
/dev/mmcblk0p1        8192   137215   129024   63M  c W95 FAT32 (LBA)
/dev/mmcblk0p2      137216 31422463 31285248 14.9G 83 Linux

Disk /dev/sda: 14.9 GiB, 15931539456 bytes, 31116288 sectors

after boot plug in card reader

Device     Boot  Start      End  Sectors  Size Id Type
/dev/sda1         8192   137215   129024   63M  c W95 FAT32 (LBA)
/dev/sda2       137216 30679039 30541824 14.6G 83 Linux

which i mou nted