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I am having a few problems with a DHCP / PXE environment, I think I know what the problem is but I really just want to see what the server is getting back.

I love tools like Wget and Wfetch for seeing exactly what is being sent back and was just wondering if there are any similar tools for DHCP that just allow me to see what is being sent back.

FYI - This is in a Data centre, I have no physical access. I rent about 7 servers and have no physical access to the switch. The servers also rely on having a fixed IP setting, I have not had much luck trying the usual techniques.

I am currently in Windows PE, but have also tried from within 2008.

When I say usual techniques, I have tried using Wireshark and Microsoft Network Monitor however I have not had any luck due to the fact that having a static IP does not issue a DHCP request.

I can have access to the BIOS and basically want to boot another server off the network - I can get in to PXE and boot Windows PE or several other (modified) ISO's, but I am just having problems with a new ISO I want to test and I think that it is getting incorrect parameters so I just want to see the raw DHCP request.

William Hilsum
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2 Answers2

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You don't mention the OS in question, what problem you're seeing, whether you're the DHCP / PXE server or client (or both), and what "usual techniques" you've tried so far. Any or all of those details would be helpful.

Having said that, I'd look to whatever sniffer software your OS has available as the first stop along the way. Presumably one or more of your computers is having the problem, so sniff there, since you can't access the switch and perform any kind of port mirroring, etc.

When I'm trying to diagnose a problem "on the wire", the first tool I reach for is a sniffer because I want to see what's happening on the wire.

Give us some details and we'll see what we can do.

Evan Anderson
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  • Sorry, editing the original question – William Hilsum Sep 17 '09 at 14:26
  • No need to be sorry... >smile< Just want to give you the best information possible. – Evan Anderson Sep 17 '09 at 15:25
  • Late Response... this was solved in the end through a hell of a lot of sniffing! I wish there was an all in one tool just for DHCP as sniffing did seem like overkill, but, it worked.... If anyone does find a tool just for DHCP, I will switch answer to that, but, for now, this did solve it! – William Hilsum Mar 08 '12 at 01:05
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You could set up a virtual machine on one of your servers and enable DHCP on the VM. Then you can test as much as you like with a sniffer running on the VM without having to make any potentially damaging network configuration changes to any of your servers (especially since the servers are rented and they most likely have vendor-specific management utilities installed and possibly some custom configuration by your hosting provider to optimize performance within that environment).

Jessica McKinnon
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