10.1 netboot on non-turbo mono slab failing at NFS

Hello all,

Disclaimer: I am very much a NeXT noob.  Most of my NetBSD activity is =
on sparc(32).

I have my NS slab booting, bootp=E2=80=99ing, tftping the boot loader, =
but it fails when getting to NFS:

NeXT>btp
boot tp(8,0,8)
Requesting BOOTP information. [0K]
Booting /boot from netbsd-10-1.internal.burn.net
    =E2=80=A2 =EF=BB=BF=EF=BB=BFNetBSD/next68k BOOT [1.8 (Mon Dec 16 =
13:88:11 UTC 28.
    =E2=80=A2 =EF=BB=BF=E2=80=BA type 1, non-turbo=20
read header failed: Input/output error load of en( ):
Input/output error
boot:

My netboot server is an amd64 NetBSD VM.  It seems that my setup to this =
point is working, and it seems that NFS is working on the server side =
correctly:

(I ran the relevant NFS daemons in debug/foreground mode)

Getting mount list.
Here we go.

got mount request from 192.168.64.42
-> rpcpath: /export/client/root/
-> dirpath: /export/client/root
Mount successful.

I fear I have something wrong in that directory on the netboot server.  =
I untarred all of the sets tgz=E2=80=99s there.  I made the swap file.  =
I made the client rc.conf, hosts etc.  I basically followed:

https://cdn.netbsd.org/pub/NetBSD/NetBSD-10.1/next68k/INSTALL.html

Here is my NFS root directory I=E2=80=99m trying to serve up:

netbsd-10-1# pwd
/export/client/root

netbsd-10-1# ls -la
total 3192
drwxr-xr-x  18 root  wheel      512 Feb  6 10:18 .
drwxr-xr-x   5 root  wheel      512 Feb  6 10:08 ..
-rw-r--r--   2 root  wheel     1186 Dec 16 08:08 .cshrc
-rw-r--r--   2 root  wheel      864 Dec 16 08:08 .profile
drwxr-xr-x   2 root  wheel      512 Dec 16 08:08 altroot
drwxr-xr-x   2 root  wheel     1024 Dec 16 08:08 bin
drwxr-xr-x   9 root  wheel    14336 Feb  6 10:19 dev
drwxr-xr-x  30 root  wheel     2048 Feb  6 10:20 etc
drwxr-xr-x   3 root  wheel     2048 Dec 16 08:08 lib
drwxr-xr-x   3 root  wheel      512 Dec 16 08:08 libdata
drwxr-xr-x   5 root  wheel      512 Dec 16 08:08 libexec
drwxr-xr-x   2 root  wheel      512 Dec 16 08:08 mnt
-rwxr-xr-x   1 root  wheel  3180888 Dec 16 08:08 netbsd
drwxr-xr-x   2 root  wheel     3072 Feb  6 10:18 rescue
drwxr-xr-x   2 root  wheel      512 Feb  6 10:18 root
drwxr-xr-x   2 root  wheel     3072 Dec 16 08:08 sbin
drwxr-xr-x   3 root  wheel      512 Feb  6 10:18 stand
drwxr-xr-x   2 root  wheel      512 Feb  6 10:10 swap
drwxrwxrwt   2 root  wheel      512 Dec 16 08:08 tmp
drwxr-xr-x  13 root  wheel      512 Feb  6 10:18 usr
drwxr-xr-x  24 root  wheel      512 Dec 16 08:08 var

What can I look at next (no pun intended) ?  Thanks.