Sorry yes, immediately after installing netmasq and configuring it to offer DHCP and TFTP, the guide states to install tftpd-hpa; this fails because dnsmasq is already bound to port :69 and, of course, it isn’t needed.
The final part not detailed is to set up the server to provide DNS services and DNS forwarding.
Looks like I will need to change the linux address to the local server as I am getting timeouts when downloading from the ubuntu repository (we live in the middle of nowhere and our internet is via cellular service and can be very tempremental).
You should do that anyway, otherwise that image gets downloaded from upstream on every single boot.
I’ve put mine on the local Apache, hence the Myhost.localdomain in the iso-url on the command line. There’s also this warning at the very bottom of said guide:
As you can see, this downloads the ISO from Ubuntu’s servers. You may want to host it somewhere on your infrastructure and change the URL to match.
So after a lot of messing around with nginx and struggling to get it to serve the required content, I reverted to using Apache2 as I had been able to configure it previously. The client successfully downloaded the iso, but then failed with “unable to find a live file system on the network” That was solved by copying the correct initrd and vmlinuz files to the tftp server root! Now I have a working system which was then successfully installed.