Sanguine
Still not working on #step1...
When I put only one records CNAME (without subdomaine) to your host, I've got this pop message :
Failed to update zone RRset castleburn.fr. IN CNAME: Conflicts with pre-existing non-CNAME RRset
This is my BIND config :
$ORIGIN castleburn.fr.
@ 3600 IN SOA ns0.online.net. hostmaster.online.net. 20180815035551 10800 3600 604800 3600
@ 86400 IN CNAME castleburn.freeflarum.com.
I just opened a ticket with my host-manager.