Root-NFS: Server returned error 13

[Brian Butcher <butcher@yebo.co.za>]

Am I on the wrong track?
Please excuse me if I am verbose, but I don't know what is relevant
here.
I am trying to run my linux box as a server for two effectively diskless
clients which will boot from a floppy.
I am using slackware 3.50 with kernel 2.0.35, and dhcp-2.0b1pl6.
To make the initial root file system for the clients I ran slakware
setup and mounted root in (e.g.) /tftpboot/192.168.77.194 and installed
the system and network files. I added to the /etc/exports file the line 
	/tftpboot/192.168.77.194 192.198.77.194(rw, no_root_squash) 
I compiled a kernel for the clients with bootp and root-NFS options. The
resulting zImage file was used to create a bootdisk by 'cat zImage >
dev/fd0'.
On booting the client with this bootdisk the the bootp is successful.
The client then reports:
	Root-NFS: Server returned error 13 while mounting
/tftboot/192.168.77.194
The server debug file shows that this message originates from the
server's mountd.
I have not been able to find any documentation on NFS error numbers.
A similar question about error 13 appeared in this list in July 1988. 	(
http://www.han.de/~gero/netboot/archive/msg01252.html ). If solved, the
solution was never published.
Can anyone help .. I have been playing with this for two weeks now.

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