so, run rpc.bootparamd. Various linux releases include it (I think
it's part of "netkit") or you can get it from the Xkernel package... 

In general, the easiest way to get netbsd up on a "foreign" server is
get Xkernel up and running *first*; fewer variables and more
documentation, you should be able to work it out step by step.  Once
that's up, you just need to change a few paths, add a swapfile, and
have it boot netbsd instead.  (There used to be a linux-Xkernel
package on sunsite, including bootparamd and other related servers for
linux...)