I have been given a couple of Termtek TK-3550 thin clients and I am trying to set them up to open into my Ubuntu 20.04 server at my home over our ethernet LAN. These devices don't have much memory so I have been following the instructions to install the "Classic, NFS-filesystem-based X2Go TCE". I have setup a Virtual Box VM, running Ubuntu 20.04 with a bridged network adapter and a permanent IP address, to be the pxe server. I have followed the instructions as best I was able but I am still having difficulties.

I think one problem is likely to be that our cheap router, which provides our DHCP server, does not allow me to nominate the "next-server" or the filename. In an attempt to address this I have installed dnsmasq on the pxe server VM and am running dnsmasq. The dnsmasq.conf is as follows:

The thin client is set to boot over LAN and the dhcp-log on the pxe server looks like this when I turn the thin client on:

I'm clearly a complete novice but it seems the thin client is finding its way to the pxe server. Unfortunately the thin client trys to boot until it times out, reporting:

"No boot filename received". It then just boots its decades old version of Windows CE. Note that when I changed the tftp-root path in dnsmasq from /opt/x2gothinclient/chroot to /srv/tftp it had some effect on the dhcp log (it nominated its terminal id in a second line) but the nett result did not change. I should add that I have exported both /opt/x2gothinclient/chroot and /srv/tftp with the NFS server. I only switched to /srv/tftp because that's where pxelinux.0 is and I assume that is the file it is looking for and failing to find.

Basically I have been trying to get this working for a couple of days without success, I have decided to seek expert help. I apologise for my ignorance, I understand that hobbists like myself are probably incredibly annoying.