Flashing or backing up your SD card » History » Version 3
Giulio Moro, 2015-09-25 12:38 AM
1 | 1 | Giulio Moro | h1. Flashing or backing up your SD card |
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2 | 1 | Giulio Moro | |
3 | 2 | Giulio Moro | How to do it under MacOs and Linux. For both these tasks you will need the dd program. It comes with many Linux distributions and is available for MacOS. |
4 | 2 | Giulio Moro | |
5 | 1 | Giulio Moro | Put your SD card in the SD card reader. We assume for the rest of this document that your SD card is /dev/mmcblk0 |
6 | 2 | Giulio Moro | |
7 | 3 | Giulio Moro | Always start by unmounting the SD card in case it is currently mounted: |
8 | 1 | Giulio Moro | <pre> |
9 | 1 | Giulio Moro | $ sudo umount /dev/mmcblk0 |
10 | 1 | Giulio Moro | </pre> |
11 | 3 | Giulio Moro | |
12 | 3 | Giulio Moro | h2. Flashing an SD card |
13 | 3 | Giulio Moro | |
14 | 3 | Giulio Moro | Whether you got an image from somewhere else or you want to flash your own backup image after you bricked your Beaglebone, do as follows: |
15 | 3 | Giulio Moro | make sure that the SD card is inserted and that none of its partitions are mounted as explained above. |
16 | 3 | Giulio Moro | Then: |
17 | 3 | Giulio Moro | <pre> |
18 | 3 | Giulio Moro | $ sudo dd if=~/bbb_images/your_own_your_precious_backup_image.img of=/dev/mmcblk0 |
19 | 3 | Giulio Moro | </pre> |
20 | 3 | Giulio Moro | As it happens, `dd` is a very simple program, so simple that it does not even display a progress bar. |
21 | 3 | Giulio Moro | If you are lucky enough to be on Linux, you can probably install pv which will display a progress bar for you: |
22 | 3 | Giulio Moro | |
23 | 3 | Giulio Moro | pv ~/bbb_images/your_own_your_precious_backup_image.img | sudo dd of=/dev/mmcblk0 |
24 | 3 | Giulio Moro | |
25 | 3 | Giulio Moro | h2. Backing up your SD card |
26 | 3 | Giulio Moro | |
27 | 2 | Giulio Moro | In case your partition is smaller than the size of the sd card, you do not need to backup the whole card, so if this is the case, run: |
28 | 2 | Giulio Moro | <pre> |
29 | 2 | Giulio Moro | $ sudo fdisk -u -l /dev/mmcblk0 |
30 | 2 | Giulio Moro | </pre> |
31 | 2 | Giulio Moro | You might get something along the lines of |
32 | 2 | Giulio Moro | <pre> |
33 | 2 | Giulio Moro | Device Boot Start End Blocks Id System |
34 | 2 | Giulio Moro | /dev/mmcblk0p1 * 63 144584 72261 c W95 FAT32 (LBA) |
35 | 1 | Giulio Moro | /dev/mmcblk0p2 144585 3743144 1799280 83 Linux |
36 | 2 | Giulio Moro | </pre> |
37 | 2 | Giulio Moro | You are interested in the higher value in the "End" column. Pass that value to dd as the count parameter: |
38 | 2 | Giulio Moro | <pre> |
39 | 3 | Giulio Moro | $ sudo dd conv=sparse count=3743144 if=/dev/mmcblk0 of=~/bbb_images/your_own_your_precious_backup_image.img |
40 | 2 | Giulio Moro | </pre> |