Skip to content

Latest commit

 

History

History
91 lines (74 loc) · 3.02 KB

clone-pi.md

File metadata and controls

91 lines (74 loc) · 3.02 KB
Raw

Clone an Image of the Pi

Instructions from a Linux desktop. For Windows, see Beebom

Determine the device path:

fdisk -l

Note that it is not and never will be sda - if you run a dd over this, you will wipe the hard drive of your machine. Device drives are typically sdb (note the sequencing) but often can be mmcblk.

What it mounts as depends on how the blocks device is registered in the Linux kernel.

  • SCSI disks are handled by drivers/scsi/sd.c and mount as sdX
  • MMC devices are handled by drivers/mmc/card/block.c and mount as mmcblk

You'll see output similar to:

...sda stuff above here...
Disk /dev/mmcblk0: 14.9 GiB, 15931539456 bytes, 31116288 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x0007131b

Device         Boot   Start      End Sectors  Size Id Type
/dev/mmcblk0p1         8192  2804687 2796496  1.3G  e W95 FAT16 (LBA)
/dev/mmcblk0p2      2804688 10362879 7558192  3.6G  5 Extended
/dev/mmcblk0p5      2809856  2875389   65534   32M 83 Linux
/dev/mmcblk0p6      2875392  3022845  147454   72M  c W95 FAT32 (LBA)
/dev/mmcblk0p7      3022848 10362879 7340032  3.5G 83 Linux

mmcblk0 is the device path we need.

Clone All Partitions

dd if=/dev/mmcblk0 of=/home/angela/Desktop/tc_backup.img bs=1M status=progress
  • Note that the in-file (if) value is only mmcblk0 and lacks pX - that's because we don't want to target partitions, we want all of them.
  • bs parameter = increases speed while writing
  • status parameter = progress display
  • A file will be created on my deskop with the filename tc-backup.img - I can use this to flash on multiple SD cards for various batteries

It took about 10 minutes to flash on an 8gb SD card (without the bs flag).

Restore Parition to a New SD Card

Place the SD card into the laptop and check what the device ID is, again.

fdisk -l

Same rules as above apply..

Now, unmount it:

umount /dev/mmcblk0p1 /dev/mmcblk0p2 /dev/mmcblk0p5 /dev/mmcblk0p6 /dev/mmcblk0p7

Flashing the new image is a reversal of the clone command:

dd if=/home/angela/Desktop/tc_backup.img of=/dev/mmcblk0 bs=1M status=progress

Now, login to the Pi and set an IP, based on the closet number:

Increment it for each machine using 172.28.4.xx; xx = closet number

pico /etc/dhcpcd.conf

On your desktop, make an SSH alias, so you can lazily enter the Pi, like so: ssh tc3pi instead of ssh pi@172.28.4.3:

Host tc3pi
HostName 172.28.4.3
Port 22
User pi
Compression yes
IdentityFile ~/.ssh/id_rsa

Add an SSH Key to Your Pi

Because you're going to have to run OS upgrades (on the Pi) at some point

Assuming you already have an SSH key, from your desktop, run (destination being the Pi's IP):

ssh-copy-id -i ~/.ssh/id_rsa.pub pi@172.28.4.3

Lazily login now:

ssh tc3pi