You can also do an FTP install by TFTP'ing an entire install image (kernel and root filesystem). You will want to do the same as the above example, except for the nfsroot and the kernel link. Instead of using /images/vmlinux, use tftpboot.img. Put it in /home/tftp and make the symlink:
cd /home/tftp ln -s tftpboot.img C7B718E8.SUN4M
Please remember to change the IP address and architecture based on your own network numbers and machine architecture.
Now all you need to do is a ``boot net'' from the SPARC and it should TFTP everything over, boot a kernel, and start the install program. You can then do an FTP install from a server near you, or you can do an NFS, hard drive, or CD-ROM install if you choose.