Install dns323-firmware-tools by entering the following commands in the terminal:
sudo apt update sudo apt install dns323-firmware-tools
Description:
build and manipulate firmware images for a range of NAS devices
This package contains programs for manipulating the firmware images used by a range of small consumer-grade NAS devices, such as the D-Link DNS-323. . These firmware images are what are used to "bundle" the kernel, initrd, and other data when uploading new firmware images using the "stock" interface. If you are already running a custom firmware, it is likely that these tools will be of no use to you, and you will need to use whatever update mechanism is provided by your firmware.
Homepage: http://theshed.hezmatt.org/dns323-firmware-tools/
Version: 0.7.3-1
Section: universe/otherosfs