When netbooting an older sparc system such as a Sun4 or Sun4c, the boot
may hang up at the end of the tftp transfer of the bootstrap due
to the tftp transfer working in 512-byte blocks. If this occurs
create a "padded" version of the bootstrap (boot or zboot) as follows:
# cd /tftpboot
# dd if=boot of=newboot obs=512 conv=osync
# mv newboot boot