Partitioning and formatting SD cards on Linux

To partition and format an SD card in Linux, follow these steps: First, connect the SD card to your PC. Then, use the fdisk command in the bash command line to partition the SD card. Finally, use the mkfs command to create a file system (format) on the SD card.

The main commands are as follows:

First, use sudo fdisk -l to confirm which device in /dev corresponds to the SD card.

Assuming we have determined that the SD card corresponds to /dev/sde, we can enter sudo fdisk /dev/sde to start the partitioning operation:

• Enter d to delete partitions. Keep entering until all partitions are deleted.
• Enter n to create the first partition as the boot partition.
• Enter t to change the partition type to W95 FAT32. Boot partitions are generally of this type.
• Enter a to set the partition as the boot partition.
• Enter n to create the second partition as the root file system partition.
• Since the root file system partition type is usually Linux, and the default partition type is already Linux, there is no need to enter t to change the partition type.
• Enter w to save and exit.

Finally, after partitioning, we can create the file systems:

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2

sudo mkfs.vfat -F 32 -n "BOOT" /dev/sde1
sudo mkfs.ext4 -L "rootfs" /dev/sde2

In the above code, the first line creates a FAT32 file system for the boot partition and names it as BOOT. The second line creates an ext4 file system for the root file system partition and names it as rootfs.