steamcache dns need to have UPSTREAM_DNS added.
add UPSTREAM_DNS ur.local.dns.ip / quad.9 / google.dns
otherwise will broke dns query other than steam related
have been using ipxe since day1 tftp on unraid. i chainloaded thru grldr, using dnsmasq.
boot into winpe 4-5 secs and i can start deploying windows / imaging / quick diagnostics.
im not linux, network, english guy like you. i speak, read and listen to 5 different languages in my daily life.
removed all my posts here because they sounds inappropriate and misleading.
sorry for trying to help, suggest and hinted.