Help with network boot

[Peter Dufault]

I want to start network booting (pc586).  I haven't been able to find 
the documentation.

I set up a FreeBSD dhcp server and a PC to boot using PXE.  I copied a 
".bt" file (I verified the corresponding .exe file works) to /tftpboot, 
and verified I can tftp it.  Then I reset the PC.

The boot ROM output on the PC shows that it gets its IP address, 
default router, etc fine and then asks for the correct boot file.  Then 
it says "File not found", says "TFTP Error - file not found", and gives 
up.  Here's the tcpdump output:

15:43:54.132972 0.0.0.0.bootpc > 255.255.255.255.bootps:  
xid:0x182425f2 secs:4 flags:0x8000 [|bootp] (ttl 20, id 0, len 576)
15:43:54.133404 sim.bootps > 255.255.255.255.bootpc:  xid:0x182425f2 
secs:4 flags:0x8000 Y:chill S:sim ether 0:80:17:24:25:f2 [|bootp] [tos 
0x10]  (ttl 16, id 0, len 328)
15:43:55.176664 0.0.0.0.bootpc > 255.255.255.255.bootps:  
xid:0x182425f2 secs:4 flags:0x8000 [|bootp] (ttl 20, id 1, len 576)
15:43:55.176913 sim.bootps > 255.255.255.255.bootpc:  xid:0x182425f2 
secs:4 flags:0x8000 Y:chill S:sim ether 0:80:17:24:25:f2 [|bootp] [tos 
0x10]  (ttl 16, id 0, len 328)
15:43:55.189330 arp who-has sim tell chill
15:43:55.189345 arp reply sim is-at 0:50:ba:4b:90:3c
15:43:55.189441 chill.2070 > sim.tftp: [udp sum ok]  35 RRQ 
"/tftpboot/chill.bt" (ttl 20, id 2,len 63)
15:43:55.194166 sim.1974 > chill.2070: [udp sum ok] udp 10 (ttl 64, id 
39723, len 38)
15:43:55.194277 chill.2070 > sim.1974: [udp sum ok] udp 17 (ttl 20, id 
3, len 45)
15:43:55.200889 chill.2071 > sim.tftp: [udp sum ok]  40 RRQ 
"/tftpboot/chill.bt" (ttl 20, id 4,len 68)
15:43:55.205411 sim.1975 > chill.2071: [udp sum ok] udp 19 (ttl 64, id 
39724, len 47)

Am I doing this right?  Can you directly boot the .bt file using the 
PXE boot?

Peter Dufault
HD Associates, Inc.