The only official way to get this file is to dump it from your own physical Nintendo DSi console using a homebrew tool.
: If you are dumping from your own hardware, tools like dumpTool are typically used. Note that some dumpers add a "no$gba footer" to the end of the file, which may cause hash mismatches, though melonDS is generally designed to handle these. Troubleshooting & Performance nand.bin melonds
– Powerful when set up correctly, but hindered by complex setup and legal gray areas. The only official way to get this file