Milk-V Duo S Extend Partition on SD Card or eMMC

The default capacity of the official Debian image root file system is about 4GB. When installing software or other data increases, there will be insufficient space. We can expand the file system to the full capacity of the SD card or eMMC.
The following uses a Mars booted from a 32G SD card as an example to introduce how to expand the capacity through commands. The expansion method for the eMMC version is also the same, just replace /dev/mmcblk1 with /dev/mmcblk0 (/dev/mmcblk1p4 with /dev/mmcblk0p4).

】Check the current status of the partitions
Use the df -h command to view the current partition status

# df -h
Filesystem Size Used Avail Use% Mounted on
udev 700M 0 700M 0% /dev
tmpfs 193M 3.3M 190M 2% /run
/dev/mmcblk1p4 3.7G 3.1G 590M 85% /
tmpfs 962M 0 962M 0% /dev/shm
tmpfs 5.0M 12K 5.0M 1% /run/lock
/dev/mmcblk1p3 100M 23M 77M 23% /boot
tmpfs 193M 60K 193M 1% /run/user/110
tmpfs 193M 24K 193M 1% /run/user/0
You can see that the device mounted in the current root partition / directory is /dev/mmcblk1p4

】Extend a partition using the fdisk command

Entering the fdisk command will take you into the command-line interactive mode of fdisk

# fdisk /dev/mmcblk1
Enter the p command to view the current partition information. You can see that the current capacity of the system partition /dev/mmcblk1p4 is 3.8G

Command (m for help): p

Disk /dev/mmcblk1: 29.12 GiB, 31267487744 bytes, 61069312 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: gpt
Disk identifier: 2D487F15-E07F-4B07-BC04-80EA297E8675

Device Start End Sectors Size Type
/dev/mmcblk1p1 4096 8191 4096 2M HiFive BBL
/dev/mmcblk1p2 8192 16383 8192 4M HiFive FSBL
/dev/mmcblk1p3 16384 221183 204800 100M EFI System
/dev/mmcblk1p4 221184 8189918 7968735 3.8G Linux filesystem
Then execute the d command to delete the system partition from the original system. You will be prompted to enter the partition number to be deleted. We want to delete /dev/mmcblk1p4, so enter 4

Command (m for help): d
Partition number (1-4, default 4): 4

Partition 4 has been deleted.

Command (m for help):

Then use the n command to create a new partition. It prompts you to enter the partition number. We still use /dev/mmcblk1p4, so enter 4.

The following prompt First sector requires you to enter the starting sector value of the new partition. The command it has helped us identify the default starting value (default 221184), which is the starting sector of the just deleted /dev/mmcblk1p4, so you can just press Enter without entering value.

Finally enter the size of the new partition. The default "default" value is the entire storage space, there is no need to enter a specific value, just press Enter and it will prompt "Do you want to remove the signature? [Y]es/[N]o:" Enter No

Command (m for help): n
Partition number (4-128, default 4): 4
First sector (34-61069278, default 221184):
Last sector, +/-sectors or +/-size{K,M,G,T,P} (221184-61069278, default 61067263):

Created a new partition 4 of type 'Linux filesystem' and of size 29 GiB.
Partition #4 contains a ext4 signature.

Do you want to remove the signature? [Y]es/[N]o: No

Command (m for help):
Execute the p command to check the current partition situation. /dev/mmcblk1p4 has been expanded to the entire storage space. Here it is 29G

Command (m for help): p

Disk /dev/mmcblk1: 29.12 GiB, 31267487744 bytes, 61069312 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: gpt
Disk identifier: 2D487F15-E07F-4B07-BC04-80EA297E8675

Device Start End Sectors Size Type
/dev/mmcblk1p1 4096 8191 4096 2M HiFive BBL
/dev/mmcblk1p2 8192 16383 8192 4M HiFive FSBL
/dev/mmcblk1p3 16384 221183 204800 100M EFI System
/dev/mmcblk1p4 221184 61067263 60846080 29G Linux filesystem

Command (m for help):
Execute the w command to save changes and exit fdisk interactive mode

Command (m for help): w
The partition table has been altered.
Syncing disks.

Finally, execute the resize2fs command to complete the file system expansion

# resize2fs /dev/mmcblk1p4
resize2fs 1.46.6-rc1 (12-Sep-2022)
Filesystem at /dev/mmcblk1p4 is mounted on /; on-line resizing required
old_desc_blocks = 1, new_desc_blocks = 4
The filesystem on /dev/mmcblk1p4 is now 7605760 (4k) blocks long.

Use the df -h command again to check the partition status. You can see that the system partition node /dev/mmcblk1p4 has been expanded to 29G

# df -h
Filesystem Size Used Avail Use% Mounted on
udev 700M 0 700M 0% /dev
tmpfs 193M 3.3M 190M 2% /run
/dev/mmcblk1p4 29G 3.1G 26G 11% /
tmpfs 962M 0 962M 0% /dev/shm
tmpfs 5.0M 12K 5.0M 1% /run/lock
tmpfs 193M 64K 193M 1% /run/user/110
tmpfs 193M 24K 193M 1% /run/user/0
/dev/mmcblk1p3 100M 23M 77M 23% /boot

TAG： Raspberry Pi Pico 2 RP2350-One Mini Board Type-A RP2350A EC200U C4-P01 Development Board QuecPython LTE Cat-1 Bluetooth GNSS Positioning 1.47 inch LCD AXS5106L TouchScreen JD9853 Display 172x320 For Arduino/Raspberry Pi/Pico/ESP32 Program Sipeed MaixCAM SG2002 RISC-V AI Camera Kit with Screen Audio WIFI6 Linux Board ESP32-S3 Industrial-Grade WiFi Relay IOT RS485 Communicator Bluetooth RoArm M2 4 DOF High Torque Serial Bus Servo ROS2 WIFI ESP NOW UART USB ST3235 QMI8658C For ESP32 ADXL354C Evaluation Board ESP32 C6 Development Board 1.47 inch LCD Touch Screen 1.47inch Display 172×320SD AXS5106L JD9853 SpotPear Finger Vein Scanner Module (B) Cortex M4F UART serial port EAL4+ security certification qualification LuckFox Raspberry Pi 5 Box Case Ki-A PCIe to RJ45 Gigabit Ethernet All Ports To Pi's USB Side Industrial CAN FD ETH RJ45 bidirectional converter CAN2.0A/2.0B Mini TV X1008 Raspberry Pi 5 PCIe to 2.5" 3.5" SATA HDD/SSD Dual Double-SATA (NOT BOOT From SATA/SSD Raspberry Pi 5 Heatsink Raspberry Pi Triple LCD HAT Raspberry Pi 3.5 inch e-Paper link (G) RYBW 384x184 For Arduino / Jetson Nano / STM32 ESP32 Thermal imaging

Milk-V Duo S 512MB SG2000 RISC V Linux Board Top-Version-Milk-V-Duo Option WiFi / EMMC-8G / POE

TAG： Raspberry Pi 5 Active Cooler Clock ornament JETSON NANO Expansion Board 4inch LCD IPS Captive TouchScreen 720&amp;amp;times;720 Display Luckfox Pico ESP32-S3 LCD MINI linux board Electronic EYE 0.71inch Round Double LCD Display Screen Arduino Raspberry Pi ESP32 Pico STM32 Arduino UNO R4 Minima Raspberry Pi Transparent LCD Jetson Orin Uninterruptible Power C Simultaneously Charging and Discharging X1201 Raspberry Pi 5 UPS Raspberry Pi 5 5-layer Case Raspberry Pi 14-inch Type-C/HDMI 4K TouchScreen 3840×2160 14inch computer Raspberry Pi CM5 IO BASE B Mini Board a Base Development Platform Compute Module 5 IO Board with EEPROM And Encryption chip USB to nRF24L01 ESP32 LVGL USB IR Infrared Thermal Imaging Camera C 45°/88° 160x120 For Phone/PC High Temp Warning/Take Photo /Recording video WiFi Wireless ESP32 DDSM Motor Driver Direct Drive Servo Hub Motors Raspberry Pi SP485EN