7.17 How can I make a ramdisk?

THIS IS UNSUPPORTED. Make sure 'ram' is configured into your kernel, and then
make device files with major 9 (both blcok and char), minor 0xVSSSSS, where
V is the volume number, SSSSS is the number of sectors in the ram disk, and
a sector is 256 bytes. For example,

mknod /dev/ram1m c 9 0x101000

makes a 1 meg ram disk. Of course, you have to make a file system on it and
mount it to make it useful:

mkfs /dev/ram1m 1024

Note that you will have to make a block device also.

This works for all 9.x systems.