[wds] WDS & DHCP Error! Help was working yesterday!

[jamin100]

I got WDS working nicely as it should just before the holiday. I then had a computer which i needed to inject some nic drivers using imagex. I did this fine and the computer went on to image fine.

 

I then come to deploy an image to my test computer (which i have already successfully images a few times) but im now getting a dhcp error

 

"WDSclient: an error occured while trying to obtain an IP address from the DHCP server. Please check to ensure that there is an operational DHCP server on this network segment"

 

If i shift+f10 i dont have an IP address and cant ping any of my servers.

Edited June 8, 2011 by jamin100

[jamin100]

UPDATE:

 

Nothing is now working! I cant deploy any images at all as i keep getting the same DHCP error.

 

What ive tried:

Created a new boot image from the Vista DVD

moved DHCP to a different server (still not on the same one as WDS)

 

 

This is crazy as I imaged a netbook with WDS yesterday and it worked fine!

[ChrisH]

Is there a rogue DHCP server affecting it? The clients maybe ok but a PXE boot might be a little more sensitive to such things.

[jamin100]

Is there a rogue DHCP server affecting it? The clients maybe ok but a PXE boot might be a little more sensitive to such things.

 

Not that I can tell but how would I check?

[ChrisH]

You would have to run something like wire shark and filter for DHCP messages such as offer and acceptance of DHCP leases or in my case in the past an old dhcp server on a Censornet box would be active with no scope and the clients would always find it first. After it refused to give an IP address multiple time the clients finally found the windows DHCP server.

I would just do a port mirror on your switch of the client you are trying to boot up or run it from your workstation and check general traffic on the network for it. If you do the port mirror you can see exactly what the client is/isn't receiving.

[jamin100]

It doesnt look like there is from what I can tell.

Its really bugging me though as I was going to use WDS to deploy my images in the summer rather than ghost!

[jamin100]

UPDATE:

one of the machines (a new netbook) that wasnt working this morning is now working fine

What i have done:

 

1. Mounted index 2 of the boot.wim file.

2. Renamed setup.exe to setupx.exe in the root of the image.

3. Edited \windows\system32\startnet.cmd in the mounted image

@echo off

@echo Loading WinPE...
wpeinit

@echo Starting networking...
:testagain
ping -n 1 SERVERNAME > NUL
if %errorlevel% == 0 goto pingok
REM wait 3 sec. and try it again
ping -n 3 127.0.0.1 >nul
goto testagain
:pingok

@echo Running Setup...
x:\setupx.exe /wds /wdsdiscover /wdsserver:SERVERNAME
4. Saved and unmounted index 2 and added to WDS.

I then tried to deploy an image but it just hung on starting Networking

 

So i just tried another clean boot.wim that i have on the WDS server and to my surprise it works!

 

So i tried the same procedure with another 2 machines, both different spec but they are still failing on getting an IP from the DHCP server! ?

 

WDS does work fine with a VirtualMachine though

[jamin100]

This still isnt working

 

Here's where im at so far;

 

I have 2 machines (1 hp, 1 NEC) that I have previously imaged through WDS fine.

When booting into the deployment bit of WDS they cannot get an IP from the DHCP server

If they boot into windows they get a IP address fine

Ipconfig wont assign them an IP either

I have injected the drivers into the boot.wim and still not working.

DHCP seems to be working fine.

PXE boot is enabled in the BIOS

 

I'm now out of ideas...

[chazzy2501]

what about your switch? Have you enabled STP fast start on your ports. I find this causes DHCP issues with ghost etc but windows is running long enough to eventually pick up an ip.

[jamin100]

what about your switch? Have you enabled STP fast start on your ports. I find this causes DHCP issues with ghost etc but windows is running long enough to eventually pick up an ip.

 

Thanks, thats my next port of call. I've asked link2ICT to enable fast port spanning on the cicso switches we have. Just waiting for them to get back to me now . . ..

[Gatt]

Network Drivers?

 

I#ve had this where it PXE boots into WDS/WInPE but then loses its drivers, meaning you may need to inject some drivers into the Boot Image or WIM if its an image file

[chazzy2501]

Incase anyone is wondering this is a really nice explanation of STP and what fast start does.

 

Spanning Tree

 

If you have recently migrated from a hub environment to a switch environment, startup connectivity delays can appear because a switch works much differently than a hub. A switch provides connectivity at the data link layer, not at the physical layer. The switch uses a bridging algorithm in order to decide if packets that are received on a port need to be transmitted out other ports. The bridging algorithm is susceptible to physical loops in the network topology. Because of this susceptibility to loops, switches run the protocol STP that causes loops to be eliminated in the topology. When you run STP, all ports that are included in the spanning tree process become active much slower than they otherwise become active as STP detects and blocks loops. A bridged network that has physical loops, without STP, breaks. Despite the time that the process involves, STP is beneficial. STP that runs on Catalyst switches is an industry-standard specification (IEEE 802.1D).

 

After a port on the switch has linked and joined the bridge group, STP runs on that port. A port that runs STP can be in one of five states:

•

blocking

 

•

listening

 

•

learning

 

•

forwarding

 

•

disabled

 

 

STP dictates that the port starts out blocking, and then immediately moves through the listening and learning phases. By default, the port spends approximately 15 seconds listening and 15 seconds learning. During the listening state, the switch tries to determine where the port fits in the spanning tree topology. The switch especially wants to know whether this port is part of a physical loop. If the port is part of a loop, the port can be chosen to go into blocking mode. The blocking mode means that the port does not send or receive user data in order to eliminate loops. If the port is not part of a loop, the port proceeds to the learning state, in which the port learns which MAC addresses live off this port. This entire STP initialization process takes about 30 seconds.

 

If you connect a workstation or a server with a single NIC card or an IP phone to a switch port, the connection cannot create a physical loop. These connections are considered leaf nodes. There is no reason to make the workstation wait 30 seconds while the switch checks for loops if the workstation cannot cause a loop. Cisco added the PortFast or fast-start feature. With this feature, the STP for this port assumes that the port is not part of a loop and immediately moves to the forwarding state and does not go through the blocking, listening, or learning states. This command does not turn STP off. This command makes STP skip a few initial steps (unnecessary steps, in this circumstance) on the selected port.

 

Taken from here:

[Jamo]

So the machine works in Windows on the same port that PXE doesn't? You should be able to eliminate the STP issue by restarting into PXE rather than powering off and on I would think?

 

When booting into the deployment bit of WDS they cannot get an IP from the DHCP server

If they boot into windows they get a IP address fine

Ipconfig wont assign them an IP either

 

 

You can get to the deployment part of WDS using PXE then? Do you have driver compatability issues? ie a dodgy one?

[jamin100]

So the machine works in Windows on the same port that PXE doesn't? You should be able to eliminate the STP issue by restarting into PXE rather than powering off and on I would think?

 

You can get to the deployment part of WDS using PXE then? Do you have driver compatability issues? ie a dodgy one?

 

Thanks,

 

Right, the pc will boot into windows and get an IP fine through DHCP.

PXE booting also works as it download the boot image from the WDS server

However when loading the boot image it says that there is an error getting an IP address from the DHCP server. If if get into a command prompt I cant force it to find an ip either with ipconfig.

 

I have injected the drivers for the computer into the boot.wim

[sted]

when booted from wds what DOES ipconfig show does it know theres a network card there or just return blank? Edited June 16, 2011 by sted

[jamin100]

http://i776.photobucket.com/albums/yy50/jamin100/IMG_20110616_090834.jpg

[sted]

by the looks id say it has no idea what network card you have so the driver isnt there / working

 

also looks like a boot.wim from vista might be worth trying one from win7

[jamin100]

Yes it is a vista boot.wim.

Whats bugging me is that this machine was only imaged about 2 weeks ago with the same boot image and it worked fine.

[john]

I know it sounds daft but have you restarted the DHCP Server (IE full on and off) and the same with your WDS box?

[Jamo]

Is there any reason why you aren't looking at MDT? It is MUCH easier to get the drivers sorted for!