error when gpxe load

i use pelican hpc that it create cluster and master node load compute
node by netboot
my NIC of comput node not support netboot i create gpxe cd to netboot
with it my comput node
by i get error this is problem at bellow . i say this at pelican forum
but thay say :
" Hi Hogat,

I'm sorry, but I don't know what is the cause of this problem. I don't
have experience with gpxe, so I really don't know how it will work.
The fact that the compute node receives an IP means that the machines
are connected properly. I don't know why tftp is timing out. Sorry,
but I don't have any ideas.

One thing you might do is set up a virtual cluster using QEMU,
Virtualbox or VMware server. This is a convenient way to learn, and it
will solve your problems of netboot. The screencast video on the
PelicanHPC homepage shows how that can be done.

Another solution is to buy an ethernet card that is equipped to do
PXE. They are pretty cheap secondhand. Are you sure your cards won't
do PXE? It is an option than is often turned off by default. You might
need to activate it in your BIOS setup.

Michael "

this is all :

Hi
at last i success to load by netboot
this all :
i  insert pelican hpc into one pc and load it then
#pelican_setup
and i select  select  "eth0    network_device_eth0  " because pc have
two Nic then
#pelican_restart_hpc
and press "NO"
and then insert cd gpxe into other pc and reboot it and in frontend
node at  #pelican_restart_hpc
i press no
but when pc's  that gpxe cd in it , load
i see follow, what is problem?

net0:00:15:f2:08:a2:c0 no PCI 02:05.0 (open)[Link:up TX0 TXE:0 RX:0
RXE:0 ] waiting for Linkup on eth0 ... ok
net0:10.11.12.3/255.255.255.0 gw 0.0.0.0
Booting from filename "pxelinux.0"
tftp://10.11.12.1/pxelinux.0 ... connection  time out (0x4c126035)
could not load tftp:10.11.12.1/pxelinux.0 :connection time out (0x4c126035)
no more Network Device

at the frontend node i have :
#cat  ~/tmp/bohsts
10.11.12.1
#
what is my mistake ? what i should to do?
oh
Michael my english is very bad?
very thanks
best regard
Hogat

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