How to Split Edge Firmware into Multiple Parts on Linux

When working with large firmware files, splitting them into smaller chunks can simplify transfer and installation on edge devices. This guide demonstrates how to split the firmware file SPFW-R3.2.2-47xi.raucb into 50 MB chunks using a Linux virtual machine. You can adapt this process for different firmware files, sizes, or naming conventions.

Step 1: Split the Firmware File

Use the split command to divide the firmware into 50 MB chunks while retaining the original file name pattern:

split -b 50M --numeric-suffixes --suffix-length=3 SPFW-R3.2.2-47xi.raucb SPFW-R3.2.2-47xi.raucb.part_

Explanation of options:

• -b 50M → chunk size of 50 MB
• --numeric-suffixes → numeric suffix for parts
• --suffix-length=3 → suffix length (e.g., 001, 002)
• SPFW-R3.2.2-47xi.raucb → original firmware file
• SPFW-R3.2.2-47xi.raucb.part_ → prefix for split parts

Before Splitting

You have the original firmware file:

SPFW-R3.2.2-47xi.raucb

After Splitting

You will see multiple part files:

SPFW-R3.2.2-47xi.raucb.part_000

SPFW-R3.2.2-47xi.raucb.part_001

SPFW-R3.2.2-47xi.raucb.part_002

...

Step 2: Optional – Calculate SHA256 Checksum

To ensure integrity, calculate the checksum of the original firmware:

sha256sum SPFW-R3.2.2-47xi.raucb > original.sha256

This will help validate the combined file later.

Step 3: Transfer Firmware Chunks to the Edge Device (Refer https://www.se.com/ca/en/faqs/FAQ000272309/ for details on file transfer )

Use a secure file transfer tool such as FileZilla to copy the split files to your edge device.

Step 4: Validate Files on the Edge Device

Log in to the edge device using SSH (e.g., via PuTTY) and confirm the files are present:

Step 5: Concatenate Split Files

Recombine the split files into a single firmware file:

cat SPFW-R3.2.2-47xi.raucb.part* > SPFW-R3.2.2-47xi.raucb

Ensure the part file names are correct and all the parts are present.

Step 6: Optional – Validate Checksum

Compare the checksum of the recombined file with the original:

sha256sum SPFW-R3.2.2-47xi.raucb

Both values should match.

Step 7: Install and Reboot

Install the concatenated firmware on the edge device and reboot:

rauc install SPFW-R3.2.2-47xi.raucb

reboot

Step 8: Validate Firmware Version

After reboot, verify the firmware version:

verinfo

Key Notes

• Adjust chunk size (50M) based on your transfer constraints.
• Always validate integrity using checksums.
• Ensure correct sequence when concatenating files.

Released for: Schneider Electric Saudi Arabia