I've spent the last month or so on and off troubleshooting netboot problems on my Foreman server. After many network traces and debug logs I figured out it wasn't writing the boot files (i.e. the files with mac address filenames) under /var/lib/tftpboot.

Today, I finally found https://community.theforeman.org/t/foreman-isnt-placing-tftp-files-into-var-lib-tftpboot-pxelinux-cfg/15641/13. (Not sure why I didn't find it via Discourse search, this was from DDG.) It turns out that Foreman won't create the boot files if there's no default subnet defined in the host group.

Has this behavior changed? I was pretty sure this server used to work, but maybe I'm confused.

Anyway, please either make the Subnet a required field for host groups, or create a UI-visible error or warning when creating a host with Network Based provisioning method set.