PXE client not seeing new Fogserver
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@george1421 Yes, I have two DHCP servers but I configured 066 on both servers.
Jim P.
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@geekyjm OK good. Then lets see what the target computer is being told.
If your fog server is on the same subnet as your target computers you can use the fog server to capture a pcap (packet capture) of the dhcp process. https://forums.fogproject.org/topic/9673/when-dhcp-pxe-booting-process-goes-bad-and-you-have-no-clue
You can either review this pcap with Wireshark or post it to a public file share site and post the link here or DM me the link and I will take a look at it.
If your target computer is on a different IP subnet than the fog server, then use Wireshark loaded onto a witness computer. Use the capture filter of
port 67 or port 68(this capture filter will block everything except dhcp). Same guidance as before review it with wireshark or post it where I can take a look.The pcap will show us who the actors are here and what are they saying.
Last bit what device is your dhcp server? (mfg and model)
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@george1421 I did update the kernel before I got your last message. It appears that the PXE client is not getting an IP address. Also, the 066 was not set up for the old Fog server, but the PXE client gets an IP and connects. So I’m not sure what I’m missing.
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@geekyjm What device is giving IP addresses for this network? Is it the fog server or some other server? Not getting an IP address is an infrastructure thing and not fog.
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@george1421 We have two windows DHCP servers that gives out IPs. When I connect a client to the old fog server it gets an IP address. When I plugin the new fog server into the same port as the old fog server and then try to connect the client it does not get an IP address. The only change I made is swapping the new fog server with the old. Same client and the same network jack.
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@geekyjm said in PXE client not seeing new Fogserver:
it does not get an IP address
Technically I can’t see how that’s possible since the FOG server is not involved with handing out IP addresses.
What (specifically) is the error you see on the target computer?
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@george1421 You are most likely correct. There is no error. The client shows that it is booting ove PXE on IPv4. It times out after around a minute. Do I need to point the Fog server to the DHCP server? When the old Fog server is connected it finds an IP address and boots normally. I feel I’m missing something network or DHCP server setting.
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@geekyjm Lets go ahead and grab a pcap of the pxe booting process. If you are uncomfortable uploading the pcap to a file share site, I can tell you what to look for. But first we need the pcap.
My intuition is telling me that your target computer is getting an IP address, but the condition you are indicating is that the target computer might be told to connect to the old fog server and its timing out and then continues to load windows. So in a way its getting an IP address but timing out downloading the ipxe boot loader.
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@george1421 I would be glad to grab a pcap of the pxe booting process. Not sure how to do it though.
When I have the old fog server connected the target desktop gets a IP within a few seconds and displays it on the screen. When I connect the new fog server in to the same jack (even tried same IP) the target desktop doesn’t show that it received an IP address. Maybe I need to setup a DHCP relay server on the new fog server?
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@geekyjm I provided the instructions in this post: https://forums.fogproject.org/post/149423
if fog and pxe booting computer on the same subnet then use the fog server. If on different ip subnets then load wireshark on a third computer on the same subnet as the pxe booting computer. The dhcp process is sent by broadcast messages. So its easy to capture the process.
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@george1421 I can’t seem to get to this link. https://forums.fogproject.org/post/149423
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@geekyjm Same thread as this, just 5th from the bottom in order. There is a link to a kb article on setting up your fog server, as well as instructions for a capture filter in wireshark if you have to go that route.
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@george1421 Ok thanks. I did a tcpdump and I will try to view it in Wire shark.
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@george1421 How do I tell if the PXE server is running on the Fog server?
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@george1421 Nevermind, I put a 067 record in the DHCP options and PXE boot worked. Thanks for your help.
Jim P.
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@geekyjm said in PXE client not seeing new Fogserver:
How do I tell if the PXE server is running on the Fog server?
If you want to get literal, there is no such thing as a PXE server. PXE is a protocol not a thing.
DHCP tells the client where to look for the boot file. Then the client downloads what its told from a tftp server. That is the pxe process in 20 words or less.
The pcap is important to ensure the client computer is being told to load the right file from the proper computer. If you look in the OFFER packet (that comes from the dhcp server). In the header there will be a {next-server} field. That should be the IP address of the fog server. There should also be a {boot-file} field, that should be ipxe.efi or a uefi system and undionly.kpxe for bios system. That should match dhcp options 66 and 67 respectivly.
