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I need to use a network boot server. However, the DHCP Server is pointing to the wrong boot image filename and server. I can't change the DHCP Server itself, since that is controlled by another department. I just need to specify an IP for the PC to boot off initially. Is there any way to do that without going through the DHCP server? Is there a setting in the Intel Boot Agent? Or from within Debian? Thanks.

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No, you need to talk to the people running the DHCP server, or put your target host on a part of the network (a different VLAN, e.g.) that doesn't see that DHCP server, and set up your own DHCP server.

Note that you should be careful if you set up your own DHCP server, even the proxyDHCP thing that heavyd mentions, because it's very easy to start serving DHCP to clients you shouldn't, which will really really annoy your network admins...

genehack
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You can use Proxy DHCP to serve the PXE boot information without touching the DHCP server managing IP addresses. There is a nice article over at Ubuntu that describes how to configure dnsmasq to do Proxy DHCP. Since you mentioned Debian, you will need to use the dnsmasq from the testing repositories (v2.48 or higher) in order to get the ProxyDHCP features.

Note from the article:

"Real" PXE clients do support the proxy DHCP specification, as do recent (> May 2009) gPXE clients. But older etherboot clients may be unable to get their boot information from a proxy DHCP server, so for those clients a normal DHCP server is needed (either dhcp3-server or dnsmasq in normal DHCP mode).

So, YMMV. Also, if your DHCP server managing IP addresses is already responding with PXE boot information the standard does not define what should happen if multiple responses are received.

heavyd
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  • Note: Etherboot is becoming VERY long in the tooth. It's not longer supposed by some of the LTSP implementations. – Magellan Dec 05 '12 at 23:33
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if the current DHCP is already providing booting information there's no way you can prevent your client for getting that offer. You can provide alternative booting information with a proxyDHCP and with the addition of a mac filter only provide that information to the desired booting PC w/o disturbing the net at all. BUT the booting station will still receive 2 completely valid booting offers. It is not defined which one the client might take and finally boot from. As said before your only safe bid is to somehow "net" isolate the booting client.

Pat
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