Oddly enough I found the solution soon after my last post.I was looking at the wrong file all along.
I completely forgot that I un-commented the line 4 of my dnsmasq.conf file while running some tests last week . I just had to re-comment that line and voila it’s finally working.

@mareta4977 I know this thread is old, but did you get FOG to work the way you wanted?

I have a single SSD with Windows/Ubuntu in dualboot but for some reason my “Multiple Partition Image - Single Disk (Not Resizable)” image is giving me issues . I would love the image to be resizable because I might deploy it to slightly smaller disks.

My question is, if I go with the option “Single Disk - Resizable” will I be able to capture the Linux partition as well?

@george1421 I think I’ve figured out the root of my issues thanks to this link : https://www.ibm.com/support/pages/pxe-uefi-mode-fails-when-dhcp-server-not-also-tftp-server-ibm-bladecenter-and-system-x
My TFTP server and my DHCP server are on different subnets.
Updating my BIOS didn’t help as suggested but the workaround 1 works like a charm. I can keep my boot option as UEFI and just change the PXE boot to legacy by disabling the “UEFI Network Stack” in my BIOS.

That explains why I never had this issue when FOG was it’s own DHCP server before using dnsmasq.

@george1421
Yes my FOG server firewall is disabled and yes I can download the ipxe.efi file from a Windows computer without any issues.

@george1421 FYR FOG is running on Kubuntu 18.4 with dnsmasq 2.79.
I got the ltsp.conf file from the FOG wiki

This is what my file looks like :

# Don't function as a DNS server:
port=0

# Log lots of extra information about DHCP transactions.
log-dhcp

# Set the root directory for files available via FTP.
tftp-root=/tftpboot

# The boot filename, Server name, Server Ip Address
dhcp-boot=undionly.kpxe,,172.20.4.252

# Disable re-use of the DHCP servername and filename fields as extra
# option space. That's to avoid confusing some old or broken DHCP clients.
dhcp-no-override

# inspect the vendor class string and match the text to set the tag
dhcp-vendorclass=BIOS,PXEClient:Arch:00000
dhcp-vendorclass=UEFI32,PXEClient:Arch:00006
dhcp-vendorclass=UEFI,PXEClient:Arch:00007
dhcp-vendorclass=UEFI64,PXEClient:Arch:00009

# Set the boot file name based on the matching tag from the vendor class (above)
dhcp-boot=net:UEFI32,i386-efi/ipxe.efi,,172.20.4.252
dhcp-boot=net:UEFI,ipxe.efi,,172.20.4.252
dhcp-boot=net:UEFI64,ipxe.efi,,172.20.4.252

# PXE menu.  The first part is the text displayed to the user.  The second is the timeout, in seconds.
pxe-prompt="Booting FOG Client", 1

# The known types are x86PC, PC98, IA64_EFI, Alpha, Arc_x86,
# Intel_Lean_Client, IA32_EFI, BC_EFI, Xscale_EFI and X86-64_EFI
# This option is first and will be the default if there is no input from the user.
pxe-service=X86PC, "Boot to FOG", undionly.kpxe
pxe-service=X86-64_EFI, "Boot to FOG UEFI", ipxe.efi
pxe-service=BC_EFI, "Boot to FOG UEFI PXE-BC", ipxe.efi

dhcp-range=172.20.4.252,proxy

@george1421 I’ve been using FOG for over a year now, and my first installation was on an isolated network with FOG acting as a DHCP server, my address was 172.27.134.72.
I had no issues when deploying images to the computers and they were always in UFEI.

Then I stumbled upon dnsmasq and decided to switch FOG to the same subnet as the school’s computers in order for the domain join to work(there are probably other ways to do this). FOG is now installed on an HP Laptop with a static address 172.20.4.252 with the DHCP service disabled.
Now the imaging works but just not with UEFI when network stack is enabled.

@alexnoel2 I’m facing the same issue as you with the same error message.

I can deploy my images to my Dell Optiplex AIO 7470 only in BIOS mode or if I disable the “UEFI Network Stack”.
As I don’t want to change the UEFI options on my 100+ computers, and out of fear that this might end up causing addition issues, could you point me to the exact line where you added the " }"

Thanks.

Oddly enough I found the solution soon after my last post.I was looking at the wrong file all along.
I completely forgot that I un-commented the line 4 of my dnsmasq.conf file while running some tests last week . I just had to re-comment that line and voila it’s finally working.

Hey Guys,
This is my first time posting on a forum like this so please bear with me. I would like to configure dnsmasq in order to use FOG with my existing DHCP server but I keep getting an error message when trying to launch dsnmasq.

Problem encountered :
I followed the guide from this post : https://forums.fogproject.org/topic/12796/installing-dnsmasq-on-your-fog-server
once I get to step 8 and I launch the command sudo systemctl restart dnsmasq I get the following message :

job for dnsmasq.service failed because the control process exited with error code.
See "systemctl status dnsmasq.service" and "journalctl -xe" for details.

I then launch the command systemctl status dnsmasq.service for more details and I get the following results :

dnsmasq.service - dnsmasq - A lightweight DHCP and caching DNS server
   Loaded: loaded (/lib/systemd/system/dnsmasq.service; enabled; vendor preset: enabled)
   Active: failed (Result: exit-code) since Mon 2021-04-12 15:01:15 CEST; 2min 0s ago
  Process: 24348 ExecStart=/etc/init.d/dnsmasq systemd-exec (code=exited, status=1/FAILURE)
  Process: 24347 ExecStartPre=/usr/sbin/dnsmasq --test (code=exited, status=0/SUCCESS)
 Main PID: 19605 (code=exited, status=0/SUCCESS)

avril 12 15:01:15 HP-ProBook-FOG systemd[1]: Starting dnsmasq - A lightweight DHCP and caching DNS server...
avril 12 15:01:15 HP-ProBook-FOG dnsmasq[24347]: dnsmasq: syntax check OK.
avril 12 15:01:15 HP-ProBook-FOG dnsmasq[24348]: dnsmasq: illegal repeated keyword at line 4 of /etc/dnsmasq.conf
avril 12 15:01:15 HP-ProBook-FOG dnsmasq[24348]: illegal repeated keyword at line 4 of /etc/dnsmasq.conf
avril 12 15:01:15 HP-ProBook-FOG dnsmasq[24348]: FAILED to start up
avril 12 15:01:15 HP-ProBook-FOG systemd[1]: dnsmasq.service: Control process exited, code=exited status=1
avril 12 15:01:15 HP-ProBook-FOG systemd[1]: dnsmasq.service: Failed with result 'exit-code'.
avril 12 15:01:15 HP-ProBook-FOG systemd[1]: Failed to start dnsmasq - A lightweight DHCP and caching DNS server.
tftp-root=/tftpboot

This i what my ltsp file looks like :
#Don’t function as a DNS server:
port=0

#Log lots of extra information about DHCP transactions.
log-dhcp

#Set the root directory for files available via FTP.
tftp-root=/tftpboot

#The boot filename, Server name, Server Ip Address
dhcp-boot=undionly.kpxe,172.20.4.252

#Disable re-use of the DHCP servername and filename fields as extra
#option space. That’s to avoid confusing some old or broken DHCP clients.
dhcp-no-override

#inspect the vendor class string and match the text to set the tag
dhcp-vendorclass=BIOS,PXEClient:Arch:00000
dhcp-vendorclass=UEFI32,PXEClient:Arch:00006
dhcp-vendorclass=UEFI,PXEClient:Arch:00007
dhcp-vendorclass=UEFI64,PXEClient:Arch:00009

#Set the boot file name based on the matching tag from the vendor class (above)
dhcp-boot=net:UEFI32,i386-efi/ipxe.efi,172.20.4.252
dhcp-boot=net:UEFI,ipxe.efi,172.20.4.252
dhcp-boot=net:UEFI64,ipxe.efi,172.20.4.252

#PXE menu. The first part is the text displayed to the user. The second is the timeout, in seconds.
pxe-prompt=“Booting FOG Client”, 1

#The known types are x86PC, PC98, IA64_EFI, Alpha, Arc_x86,
#Intel_Lean_Client, IA32_EFI, BC_EFI, Xscale_EFI and X86-64_EFI
#This option is first and will be the default if there is no input from the user.
pxe-service=X86PC, “Boot to FOG”, undionly.kpxe
pxe-service=X86-64_EFI, “Boot to FOG UEFI”, ipxe.efi
pxe-service=BC_EFI, “Boot to FOG UEFI PXE-BC”, ipxe.efi

dhcp-range=172.20.4.252,proxy

Im using Kubuntu version 18.04 with dnsmasq version 2.79

This only occurs if I copy ltsp.conf in /etc/dnsmasq.d directory. If there is no file in that directory dnsmasq runs fine without any issues.I’m not a linux nerd and I’ve spent over a week on this issue to no avail.