1

Got a weird one here and I’m not sure where the problem lies, but might be network related.

I have a new WDS server with some boot images on it that I’m testing. It’s sitting on a VMware hypervisor on our data VLAN. I created another VM on the data VLAN and boom, it loads the Windows 10 boot image.

When I try and PXE boot from a physical machine on the same VLAN it can’t find the WDS server. I’m wondering if I’m losing broadcast traffic somewhere between the physical machine and the WDS server even though it’s on the same VLAN.

Any suggestions?

2 Spice ups
2

Are they getting DHCP from the same server in the data vlan?

Is DHCP options configured?

3

WDS and DHCP are in the same VLAN. DHCP is running on a Cisco 2901 router. The odd thing is, when I add options 66 and 67 the VM will no longer PXE boot. If I remove them the VM PXE boots just fine. The physical PC just doesn’t work period. It searched for the image but is never able to load it. I’ve tested multiple machines.

Playing around if I add option 66 I get PXE-E53. If I add option 67 I get PXE-E32. Either of these causes the VM to no longer boot from WDS.

4

Why is your server not doing DHCP? Why have you got that on a router, ideally you’d want your windows box doing DHCP unless you are using DHCP relay or helpers

5

It’s a large, inherited network. From what I understand, DHCP options aren’t required if WDS, DHCP and clients are on the same VLAN.

Roadmap is to migrate DHCP to a Windows Server, it just hasn’t happened yet.

6

If Windows if not the DHCP you need helpers. Take a look here

7

Check the PXE response tab in WDS to be sure it’s configured appropriately - with an “unknown” client it might not answer the call.

1 Spice up
8

I configured everything per the article and now get PXE-E32: TFTP Open Timeout

9

I wonder if I need to add IP helpers even though DHCP and WDS are on the same VLAN because of the fact that DHCP is running off of a router. I might give that a try and see what happens.

10

Its listed in the link I gave you, if you do not use a windows DHCP helpers are required.

1 Spice up
11

I needed a way to enable clients to first get an IP from the DHCP server, and then be properly directed (across different VLANs) to the WDS server.

There turned out to be two ways of accomplishing this goal:

Configuring routers to forward broadcasts (Setting Up IP Helpers)DHCP options to direct PXE clients to an appropriate NBP to download

12

So I got it working! I read a TechNet article about how PXE clients will often ignore DHCP options 66 and 67 from Cisco IOS concerning WDS. I added the “next-server” option to the DHCP pool on the router and now it works like a charm!