i looked around a bit on fmans homepage and apparently netdisk is a project for connecting c64/c128 to an amiga
NetDisk II for C64/128 - Amiga
This is a networking project to connect a Commodore 64/128 to an Amiga, which will act as a server allowing you to access the hard disk drive of the Amiga from the C64/128. There are numerous similar projects around the world and mine is not really special in any way - it's just mine.

Actually, I made the first version way back in 1990/1991 at a time when I was not aware of such an existing project!
Download
Until the next version is ready for release, download is not available at this time due to horrendous bugs in the current version. <grin>