This is all in the hekate sticky...
2. Using a FAT32 or an exFAT with smaller space than 29.1GiB:
This will trigger the automatic partial backup.
In this mode it will start backing up in 2GB parts or in 1GB if you have 8GB and smaller card.
It backups your eMMC, until it fills your card. It also uses a file called partial.idx, so it know which is the next part to backup.
When this is done you will see a similar message like the following procedure:
- After the session is done, press any key and Power off or Reboot rcm (if you want to skip step 3) Switch from the main menu
- Move the files from SD card to your PC to free some space
Don't move the partial.idx file! This file, keeps tabs on which is the next part to backup.
- Unplug and re-plug USB while pressing Vol+ (skip if you rebooted into rcm from hekate's main menu)
- Run hekate_ctcaer_1.5.1.bin again and press Backup eMMC RAW GPP to continue with the next parts.
- Repeat steps 1-4 until you have 15 2GiB or 30 1GB files
- Join the files with your favorite cmd/app or use the scripts provided
For step 6, there are also scripts inside a zip, provided in the download link below. Choose the correct one based on the parts size (15 x 2GB or 30 x 1GB) and based on your OS.
Notice 1: Users that have a 8GB SD card and less, it will automatically backups with 1GB parts.
Notice 2: If you have an unfinished partial backup and want to start anew, delete the partial.idx file first.
Warning: When backing up the eMMC, in parts, you should not power on the switch normally and boot to Switch OS before done. Otherwise your finished backup will probably corrupt, because Switch OS writes on your eMMC even if it seems you done nothing.