admin is the one container here that reaches something by a mesh name:
the database, bound in database.env. A mesh name is answered by the
machine's resolver, which the runtime hands every container that does
not name its own (novox/hq ADR 0148); Mailu's unbound knows no mesh
name, and since the mesh stopped copying names into containers admin
could not find its database. The others keep unbound — rspamd needs a
validating resolver for DNSBL lookups and asks for no mesh name.
jschoubben