Installation

please ,help!

using serial console to connect the net4801,and write commad boot ,show this :
> boot

NSC DP83815/DP83816 Fast Ethernet UNDI, v1.03
Copyright (C) 2002, 2003 National Semiconductor Corporation
All rights reserved.

Pre-boot eXecution Environment  PXE-2.0 (build 082)
Copyright (C) 1997-2000  Intel Corporation

PXE-E61: Media test failure, check cable
PXE-M0F: Exiting MacPhyter PXE ROM.

No Boot device available, enter monitor.


comBIOS Monitor.   Press ? for help.

use physdiskwrite to write this image onto usb flash drive.

plug in the USb disk to net4801,and boot the system,show this No Boot device available, enter monitor.
whether is the comBIOS does not support booting from USB?

USB boot is not supported on a 4801.

http://wiki.soekris.info/Can_I_boot_my_Soekris_box_from_USB

You can boot to a CF card however.

I find a  CF card ,which is bigger than 2G,and cann't to write embeded_1.34.img in the card,HOW should I do?

If you are using physdiskwrite, you must use the -u command line switch to enable writing to media larger than 2GB.

whether the CF card must be plug in board ,and not to using the USB line?

I do not understand your question.

Plug the CF card in a Windows computer with a USB card reader and run physdiskwrite.

http://m0n0.ch/wall/installation_embedded.php

http://m0n0.ch/wall/screencasts/Writing%20the%20Flash%20card/