@pcnr I noticed this issue so many years a go. It may be issues refering undionly.kpxe file. You can find some solutions from this forum about this. In my case I did following:

Make a backup of /tftpboot/undionly.kpxe to undionly.kxpe.bak; Copied /tftpboot/undionly.kkpxe to undionly.kpxe.

So at next time, this stuck problem was solved.

Yes, you are right!
I can confirm that it is still functional.
Install clean Windows 11 + drivers + all the updates -> configure windows as you like it -> sysprep -> shutdown -> Image -> Deploy.

Although, I have searched the answer for the main question, to sysprep or not, for years!
What I mean, is that if you sysprep, some of the Windows settings and configuration will be wiped out during the sysprep, so you cannot configure image 100% ready and need some manual steps after the cloned pc (deployed) boots up.
Of course those manual configurations can be automated (by a script or some other way), but still, it would be nice that image can be setup without sysprepping if it is not needed anymore in Win10/11.

I have tested hundreds of PC-s in domain environment without sysprepping - they work flawlessly, no issues with Domain, WSUS or other things, but I am little bit worried, that if some issues arise, e.g some weird errors then I must reinstall all the deployed pc-s with sysprepped images…

Can somebody confirm?

Yes, I understand, that without sysprep, all the PC-s deployed from the same image will be using same SID, but is it bad somehow?
Can someone confirm that for Intune it is also OK?
Domain doesn’t care, WSUS either, but what else might break?

@hammerc807

This is what I had to do, was in the same boat.

Go to /opt/fog/.fogsettings

Remove the sysv-rc-conf entry from the packages line from there. (Reference: https://github.com/FOGProject/fogproject/issues/797)

Lower down in the same file, set “php_ver=‘8.2’” to “php_ver=‘8.4’”

Exit and save.

Then I had to remove symlinks in Apache that were using the old php modules:

sudo unlink /etc/apache2/mods-enabled/php8.2.conf
sudo unlink /etc/apache2/mods-enabled/php8.2.load

Then add the new links:

sudo ln -s /etc/apache2/mods-available/php8.4.conf /etc/apache2/mods-enabled/php8.4.conf
sudo ln -s /etc/apache2/mods-available/php8.4.load /etc/apache2/mods-enabled/php8.4.load

Okay - So what killled this installation was the fact a 1.5.9 csv load was imported into my 1.5.10.1698 FOG - this killed a bunch of features and I eded up having to reinstall.

I’m also interested in knowing if a solution exists.

@rodluz yes, directly from 1.5.10.1754 to 1.5.10.1763 when I saw the prompt in the FOG gui that I’m not using the latest version - it was up to date before.

in 1.5.10.1754 recapture didn’t added up, just updated the image size to the latest one.

I have just discovered that somehow all the MACs are changing sometime after the final successful DHCP lease.
My DHCP server is set to only answer to specific MACs, so if I add in the “new” one, it works.
No idea how this is happening, I’ve never seen MACs just suddenly change like this.
It sucks that now I have another MAC per server to deal with, but at least it’s working.

@Greg-Plamondon I’m going to try delving into this but I’ve been very busy with other things and just haven’t gotten around.

I do appreciate the patience and assistance.

The changes you were doing that fixed the problem, please implement them again and you should be back to functional

Once that is done, do you mind doing a diff between that file and the relevant file in the git repository side:

Files I think you changed were under: <path>/<to>/<installer>/packages/service/<servicename>/<servicefile>

I’m not seeing any issues on my test systems.

not really sure why it isn’t working either.

I believe you were editing the files in /opt/fog/service/<servicename>/<servicefile>

So you would do:

diff -u <path>/<to>/<installer>/packages/service/<servicename>/<servicefile> /opt/fog/service/<servicename>/<servicefile>

@Greg-Plamondon
Hi,

we got a dhcp server. The computer got network, the path to the efi file is connected.
I have no access to the dhcp settings that i could set the next-server or anything else.
But i think the efi file maybe is corrupt? i have tried to edit the efi file, but then the boot stick does not work anymore.

@Exsival When you say “Causing the fog server to crash” what exactly do you mean?

If it’s just a “saying” I can understand that but from a technical standpoint what this means is completely different and would need logs. If all you mean is the machine in quesiton is hanging, that’s a different issue altogether. I highly doubt the whole FOG Server is crashing.

@Tom-Elliott apologies for the delay but here is what I see in the error log when this occurs:

For context the 'Client IP Detected as <IP ADDRESS> is a small modification to the Subnet Groups plugin which I log the IP of the client checking in, this is working as intended.

The ‘PHP Fatal error’ is what I only see when we have the chain loading error.

I can confirm this is working on: 1.5.10.1734 as I have rolled back any sites to this version and have seen no issues.

[Mon Feb 23 15:07:55.208763 2026] [proxy_fcgi:error] [pid 501804] [client 10.9.209.159:33595] AH01071: Got error 'PHP message: SubnetGroup Hook: Client IP Detected as 10.9.209.159; PHP message: PHP Fatal error: Uncaught ValueError: min(): Argument #1 ($value) must contain at least one element in /var/www/fog/lib/fog/image.class.php:496\nStack trace:\n#0 /var/www/fog/lib/fog/image.class.php(496): min()\n#1 /var/www/fog/lib/fog/image.class.php(389): Image->getPrimaryGroup()\n#2 /var/www/fog/lib/fog/bootmenu.class.php(1472): Image->getStorageGroup()\n#3 /var/www/fog/lib/fog/bootmenu.class.php(469): BootMenu->getTasking()\n#4 /var/www/fog/service/ipxe/boot.php(52): BootMenu->__construct()\n#5 {main}\n thrown in /var/www/fog/lib/fog/image.class.php on line 496' [Mon Feb 23 15:08:27.815241 2026] [proxy_fcgi:error] [pid 501806] [client 10.9.209.159:1025] AH01071: Got error 'PHP message: SubnetGroup Hook: Client IP Detected as 10.9.209.159; PHP message: PHP Fatal error: Uncaught ValueError: min(): Argument #1 ($value) must contain at least one element in /var/www/fog/lib/fog/image.class.php:496\nStack trace:\n#0 /var/www/fog/lib/fog/image.class.php(496): min()\n#1 /var/www/fog/lib/fog/image.class.php(389): Image->getPrimaryGroup()\n#2 /var/www/fog/lib/fog/bootmenu.class.php(1472): Image->getStorageGroup()\n#3 /var/www/fog/lib/fog/bootmenu.class.php(469): BootMenu->getTasking()\n#4 /var/www/fog/service/ipxe/boot.php(52): BootMenu->__construct()\n#5 {main}\n thrown in /var/www/fog/lib/fog/image.class.php on line 496' [Mon Feb 23 15:09:00.456158 2026] [proxy_fcgi:error] [pid 501802] [client 10.9.209.159:1555] AH01071: Got error 'PHP message: SubnetGroup Hook: Client IP Detected as 10.9.209.159; PHP message: PHP Fatal error: Uncaught ValueError: min(): Argument #1 ($value) must contain at least one element in /var/www/fog/lib/fog/image.class.php:496\nStack trace:\n#0 /var/www/fog/lib/fog/image.class.php(496): min()\n#1 /var/www/fog/lib/fog/image.class.php(389): Image->getPrimaryGroup()\n#2 /var/www/fog/lib/fog/bootmenu.class.php(1472): Image->getStorageGroup()\n#3 /var/www/fog/lib/fog/bootmenu.class.php(469): BootMenu->getTasking()\n#4 /var/www/fog/service/ipxe/boot.php(52): BootMenu->__construct()\n#5 {main}\n thrown in /var/www/fog/lib/fog/image.class.php on line 496' [Mon Feb 23 15:09:33.088040 2026] [proxy_fcgi:error] [pid 501802] [client 10.9.209.159:6935] AH01071: Got error 'PHP message: SubnetGroup Hook: Client IP Detected as 10.9.209.159; PHP message: PHP Fatal error: Uncaught ValueError: min(): Argument #1 ($value) must contain at least one element in /var/www/fog/lib/fog/image.class.php:496\nStack trace:\n#0 /var/www/fog/lib/fog/image.class.php(496): min()\n#1 /var/www/fog/lib/fog/image.class.php(389): Image->getPrimaryGroup()\n#2 /var/www/fog/lib/fog/bootmenu.class.php(1472): Image->getStorageGroup()\n#3 /var/www/fog/lib/fog/bootmenu.class.php(469): BootMenu->getTasking()\n#4 /var/www/fog/service/ipxe/boot.php(52): BootMenu->__construct()\n#5 {main}\n thrown in /var/www/fog/lib/fog/image.class.php on line 496' [Mon Feb 23 15:10:05.672334 2026] [proxy_fcgi:error] [pid 501803] [client 10.9.209.159:16900] AH01071: Got error 'PHP message: SubnetGroup Hook: Client IP Detected as 10.9.209.159; PHP message: PHP Fatal error: Uncaught ValueError: min(): Argument #1 ($value) must contain at least one element in /var/www/fog/lib/fog/image.class.php:496\nStack trace:\n#0 /var/www/fog/lib/fog/image.class.php(496): min()\n#1 /var/www/fog/lib/fog/image.class.php(389): Image->getPrimaryGroup()\n#2 /var/www/fog/lib/fog/bootmenu.class.php(1472): Image->getStorageGroup()\n#3 /var/www/fog/lib/fog/bootmenu.class.php(469): BootMenu->getTasking()\n#4 /var/www/fog/service/ipxe/boot.php(52): BootMenu->__construct()\n#5 {main}\n thrown in /var/www/fog/lib/fog/image.class.php on line 496' [Mon Feb 23 15:10:38.336356 2026] [proxy_fcgi:error] [pid 571479] [client 10.9.209.159:43335] AH01071: Got error 'PHP message: SubnetGroup Hook: Client IP Detected as 10.9.209.159; PHP message: PHP Fatal error: Uncaught ValueError: min(): Argument #1 ($value) must contain at least one element in /var/www/fog/lib/fog/image.class.php:496\nStack trace:\n#0 /var/www/fog/lib/fog/image.class.php(496): min()\n#1 /var/www/fog/lib/fog/image.class.php(389): Image->getPrimaryGroup()\n#2 /var/www/fog/lib/fog/bootmenu.class.php(1472): Image->getStorageGroup()\n#3 /var/www/fog/lib/fog/bootmenu.class.php(469): BootMenu->getTasking()\n#4 /var/www/fog/service/ipxe/boot.php(52): BootMenu->__construct()\n#5 {main}\n thrown in /var/www/fog/lib/fog/image.class.php on line 496' [Mon Feb 23 15:11:10.976801 2026] [proxy_fcgi:error] [pid 501803] [client 10.9.209.159:36391] AH01071: Got error 'PHP message: SubnetGroup Hook: Client IP Detected as 10.9.209.159; PHP message: PHP Fatal error: Uncaught ValueError: min(): Argument #1 ($value) must contain at least one element in /var/www/fog/lib/fog/image.class.php:496\nStack trace:\n#0 /var/www/fog/lib/fog/image.class.php(496): min()\n#1 /var/www/fog/lib/fog/image.class.php(389): Image->getPrimaryGroup()\n#2 /var/www/fog/lib/fog/bootmenu.class.php(1472): Image->getStorageGroup()\n#3 /var/www/fog/lib/fog/bootmenu.class.php(469): BootMenu->getTasking()\n#4 /var/www/fog/service/ipxe/boot.php(52): BootMenu->__construct()\n#5 {main}\n thrown in /var/www/fog/lib/fog/image.class.php on line 496'```

@Tom-Elliott

So I tested current release, and it seems you were able to fix it. It registers new hosts correctly now. However, you still have errors in sed used to enable USB_HCD_USBIO in iPXE compilation to fix non-working keyboard mentioned here: https://forums.fogproject.org/topic/17870/fog-ipxe-menu-no-input/

You have TAB in your sed, but it doesn’t work correctly. So lines number 80-82:

sed -i 's+//#define USB_HCD_USBIO+#define USB_HCD_USBIO+g' config/usb.h sed -i 's+//#undef USB_KEYBOARD+#define USB_KEYBOARD+g' config/usb.h sed -i 's+//#undef USB_EFI+#undef USB_EFI+g' config/usb.h

should be:

sed -i 's+//#define USB_HCD_USBIO+#define USB_HCD_USBIO+g' config/usb.h sed -i 's+#undef USB_KEYBOARD+#define USB_KEYBOARD+g' config/usb.h sed -i 's+#define USB_EFI+#undef USB_EFI+g' config/usb.h

TAB after define and undef makes difference and current iPXE release have different syntax. They have:

#define USB_EFI //#define USB_HCD_USBIO #undef USB_KEYBOARD

So we need to uncomment define USB_HCD_USBIO, switch undef USB_KEYBOARD to define and switch define USB_EFI to undef.

@thezman007 I would say the pcap file you provided is a model of how a proxy dhcp and dhcp server should interact. The first part of the pcap is perfect.

The second part starting at second #19. The client issues a dhcp discover and the dnsmasq answers right away, the client had to issue a second discover request before the main dhcp server @ 2.2 address responded. This pattern is repeated at the end of the pcap (you can see this if you look at the pcap with wireshark).

So this is only me reading the tea leaves but I think there is something up with your main dhcp server because its being slow to respond to dhcp requests. Understand I only can see 25 second pcap but I find it abnormal. When things go sideways (and it probably will) get a pcap of the failure, that’s going to tell us what’s missing.

I’m going to remove your pcap from your post because its not needed now.

@george1421 said in PXE issues:

@Jamaal This problem is solvable but it make take some effort on your part.

Lets start with the basics.

For the DHCP IP zone where your pxe booting clients live, you need to set dhcp options 66 to the IP address of your fog server. And for dhcp options 67 that needs to be snponly.efi or snp.efi. With those settings configured on a MS Windows based dhcp server a pxe booting client should boot. Make sure on your dhcp server that is responding to bootp and dhcp requests. Its been a while since I messed with windows but on the dhcp server there should be a setting of dhcp bootp or both. Select both.

Now lets talk about WDS for a second. A WDS server can use dhcp options 66 and 67 as above, but it can also run a proxy dhcp service that tells the client to ignore the dhcp options and come talk to it for boot information after it gets an IP address for the dhcp server. This maybe called a netboot service or something like that on your WDS server. Its not part of the main WDS service. If this service is still enabled it will override any settings you make in dhcp for pxe booting.

So how do you figure this out to what’s wrong?

The easiest and most complicated issue is to identify what is flying down your network during the pxe booting process. You can do this with wireshark on a witness computer (computer not part of the pxe booting process). This witness computer can either be a ms windows or linux computer, the key is to have wireshark loaded. When you start up a capture use a capture filter of port 67 or port 68 or port 4011 That will limit what wireshark sees to only the dhcp packets. Make sure the witness computer is connected to the same subnet as the pxe booting computer.

Start the packet capture and then attempt to pxe boot the target computer. Continue to capture the packet until the pxe booting computer either reaches the fog iPXE menu or errors out. Then stop the capture.

In the top section you should see the DORA (discover, offer, request, and finally ack/nack) process. The process goes as follows:
Client -> Discovery
Server-> Offer
Client -> Request
Server -> Ack/Nack

In this process you are most interested in the one or more OFFER packets. In a normal network you should only see one OFFER packet. When WDS is involved you will see one OFFER packet from your main dhcp server and a second OFFER packet from your WDS server. If you are seeing the OFFER from your WDS server then you don’t have the proxy-dhcp service disabled, and that is causing your issue. If you are seeing two offer packets from two different dhcp servers, such as a primary / secondary setup make sure both dhcp server are configured to boot from FOG server.

Now what do you do if you only have one OFFER packet and its still not working. This is where you need to select the OFFER packet and then look at the data in the parameters box. There will be the bootp fields of next-server and boot-file these need to be configured for the fog server IP and snp.efi. Then in the dhcp options section options 66 and 67 need to be set correctly. If one or the other sections are not set correctly you will get random machines not booting while others are.

If you can’t figure it out save the packet capture file “be sure you only captured the dhcp process” and up load the file to a file share site and post the link here and one of us will take a look to see what’s wrong. But I think from what I covered here you should be able to figure out what the pxe booting client is being told to do incorrectly.

George,

I ran the idea with the system administrator at my job and of course he was doubtful (conceited), he turned off the server thinking that would solve the issue. I ended up looking at an older forum and made a USB with the ipce file and booted up the machines that were given me issues and that worked. You guys can close this and mark as resolved. Again, I appreciate your guidance on this.