How to make a bootable sd card to make an another sd card and backup the sd card image
It is very simple way to take the back up the bootable sd card using linux operating system.
plug the sd card to your computer using sd card reader.
$dmesg [ 31.556064] usb 2-2: new high-speed USB device number 3 using ehci-pci [ 31.688949] usb 2-2: New USB device found, idVendor=12d1, idProduct=14fe [ 31.688956] usb 2-2: New USB device strings: Mfr=2, Product=1, SerialNumber=0 [ 31.688959] usb 2-2: Product: HUAWEI Mobile [ 31.688962] usb 2-2: Manufacturer: HUAWEI [ 31.767838] usb-storage 2-2:1.0: USB Mass Storage device detected [ 31.767930] scsi6 : usb-storage 2-2:1.0 [ 31.768030] usb-storage 2-2:1.1: USB Mass Storage device detected [ 31.768221] scsi7 : usb-storage 2-2:1.1 [ 31.768290] usbcore: registered new interface driver usb-storage [ 32.764712] scsi 6:0:0:0: CD-ROM HUAWEI Mass Storage 2.31 PQ: 0 ANSI: 2 [ 32.768079] sr1: scsi-1 drive [ 32.768383] sr 6:0:0:0: Attached scsi CD-ROM sr1 [ 32.768514] sr 6:0:0:0: Attached scsi generic sg2 type 5 [ 32.770148] scsi 7:0:0:0: Direct-Access HUAWEI SD Storage 2.31 PQ: 0 ANSI: 2 [ 32.772460] sd 7:0:0:0: Attached scsi generic sg3 type 0 [ 32.773505] sd 7:0:0:0: [sdb] Attached SCSI removable disk [ 333.302757] usb 2-2: USB disconnect, device number 3 [ 385.785124] r8169 0000:09:00.0 eth0: link up [ 385.785139] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready [ 398.706478] r8169 0000:09:00.0 eth0: link down [ 400.863146] r8169 0000:09:00.0 eth0: link up [ 1212.397273] mmc0: new SD card at address aaaa [ 1212.412069] mmcblk0: mmc0:aaaa SU02G 1.84 GiB [ 1212.414083] mmcblk0: p1 [ 1212.509030] mmcblk0: error -110 transferring data, sector 3862264, nr 8, cmd response 0x900, card status 0x80000b00 [ 1212.509039] mmcblk0: retrying using single block read
To find the name device name of your sd card "mmcblk0"
To backup the sd card data in to your home folder.
$sudo dd if=/dev/mmcblk0 of=~/sd-card-copy.img $cd ~ $ll
Make sure to check the image memory size.
To restore the data and make a boot-able memory card.
$sudo dd bs=1M if=~/sd-card-copy.img of=/dev/mmcblk0