The mesh's one resolver: its seat, a provider's address, zones, and a node's hosts file (hq ADR 0194, 0196, 0199)

- mesh-dns-resolver: a mesh seat delivering wildcard-resolution, so every node's resolver
  configuration resolves to its one holder; node-dns-resolver kept until nothing claims it.
- ${bound:<provision>:address}: the providing machine's private address, for the one consumer
  that cannot use a name — a machine's resolver configuration.
- zone: a module declares the zone it answers and the listen that answers it; the controller
  settles it per node, refuses duplicates and shadowing, and hands the resolver .Zones to forward.
- node-hosts-file: a node seat whose holder owns /etc/hosts, with entries/add/remove.
The resolver tests follow the catalogue: no runtime dns (containers copy the machine's resolvers),
live-restore held by resolv-conf, resolv.conf naming the resolver by address then a public one.

cmd/mesh-controller/network_test.go

@@ -254,11 +254,10 @@ func theResolver(t *testing.T) catalogue.Manifest {
 	return m
 }
 
-// The resolver is handed every machine on the private network as a wildcard, the same set and the
-// same source as the hosts file, and is handed it again when a machine leaves — through the
-// module's own manifest asking for the fact, with no module of the mesh's own in between (hal
-// dnsmasq-app conversion, novox/hq 08-connectivity). The runtime on that machine is pointed at the
-// machine's own address, where the resolver answers for its containers.
+// The resolver is handed every machine on the private network as a wildcard, and is handed it again
+// when a machine leaves — through the module's own manifest asking for the fact, with no module of the
+// mesh's own in between (hal dnsmasq-app conversion, novox/hq 08-connectivity). It is the mesh's one
+// resolver (ADR 0194), and the container runtime is given no resolver of its own (ADR 0196).
 func TestTheResolverIsToldEveryMachineOnTheNetworkAndToldAgainWhenOneLeaves(t *testing.T) {
 	open := aMesh(t)
 	ctx := t.Context()
@@ -293,11 +292,12 @@ func TestTheResolverIsToldEveryMachineOnTheNetworkAndToldAgainWhenOneLeaves(t *t
 			t.Errorf("the resolver's machines lack %q:\n%s", want, first)
 		}
 	}
+	// The container runtime is given no resolver of its own (novox/hq ADR 0196): it copies its
+	// machine's, which name the mesh's resolver first. A `dns` key would be a second account of where a
+	// container asks, read only when the runtime starts.
 	for _, r := range composed(t, open, "anchor").Resources {
 		if r["id"] == "dnsmasq.runtime-dns" {
-			if !strings.Contains(r["content"].(string), `"10.77.0.1"`) || r["into"] != "json" {
-				t.Errorf("the runtime is not pointed at this machine's own address, written into its file: %v", r)
-			}
+			t.Errorf("the resolver still writes the runtime's own dns: %v", r)
 		}
 	}
 

cmd/mesh-controller/plan.go

@@ -657,6 +657,13 @@ func renderingFor(ctx context.Context, open *stores, node string,
 		machines[name] = at
 	}
 
+	// And every zone a module in the mesh answers itself (novox/hq ADR 0199), for the mesh's resolver
+	// to forward.
+	zones, err := zonesInTheMesh(ctx, open)
+	if err != nil {
+		return catalogue.Rendering{}, inventory.Node{}, err
+	}
+
 	// **The bus is never public** (novox/hq ADR 0169). It was a foundation port — widened from the
 	// broker's own `from: mesh` to from-anywhere on the broker's host, so a machine could enrol
 	// before it had an address on the private network. A machine joins through the tunnel now, and
@@ -726,14 +733,79 @@ func renderingFor(ctx context.Context, open *stores, node string,
 		BusMembership: memberships[node],
 		Settings:      settings, Generators: gens, Grants: grants, Needed: needed, Ports: ports,
 		Certificate: certificate, Authority: authority, Mesh: private, Names: names,
-		Machines: machines,
-		Suffix:   overlay.Suffix(), MeshRange: meshRange, TunnelInterface: overlay.Interface, Accounts: accounts, Foundation: foundation,
+		Machines: machines, Zones: zones,
+		Suffix: overlay.Suffix(), MeshRange: meshRange, TunnelInterface: overlay.Interface, Accounts: accounts, Foundation: foundation,
 		Kept: kept, Adopted: record.Adopted, OutwardLinks: outwardLinks,
 		Given: given, Taken: taken, Seats: seats, ArtifactStore: artifactStore, Built: built,
 		BusUsers: busUsers,
 	}, record, nil
 }
 
+// zonesInTheMesh is every zone a module in the mesh declares, where the mesh placed it (novox/hq ADR
+// 0199): the zone settled from that node's settings, the node's private address, the port the
+// answering listen is published on there.
+//
+// Read across every machine's resolution, as the roster once read routed names: a node whose set does
+// not compose declares nothing and is passed over, so one broken machine does not cost the rest their
+// zones; a store that cannot be read is raised, naming the machine, because returning the zones
+// without it would withdraw them from the resolver as if the operator had (novox/hq 04-ISSUES/152).
+// What the mesh refuses about the zones together — one declared twice, one shadowing the mesh's
+// suffix or a node's public domain — is refused here, by name.
+func zonesInTheMesh(ctx context.Context, open *stores) ([]catalogue.ZoneAt, error) {
+	inv := open.inventory
+	places, err := inv.Overlays(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("where the machines are cannot be read: %w", err)
+	}
+	address := map[string]string{}
+	for _, p := range places {
+		if strings.TrimSpace(p.Address) != "" {
+			address[p.Name] = p.Address
+		}
+	}
+	nodes, err := inv.Nodes(ctx)
+	if err != nil {
+		return nil, fmt.Errorf("which machines the mesh has cannot be read: %w", err)
+	}
+	var zones []catalogue.ZoneAt
+	var public []string
+	for _, n := range nodes {
+		plan, _, err := planFor(ctx, open, n.Name)
+		switch {
+		case unresolvable(err):
+			continue
+		case err != nil:
+			return nil, fmt.Errorf("the zones %s answers cannot be read: %w", n.Name, err)
+		}
+		if plan.PublicDomain != "" {
+			public = append(public, plan.PublicDomain)
+		}
+		for _, m := range plan.Modules {
+			if m.Zone == nil {
+				continue
+			}
+			at := address[n.Name]
+			if at == "" {
+				// Not on the private network yet: nothing could reach its answerer.
+				continue
+			}
+			published, layers, err := portsGivenOn(ctx, inv, n.Name, m)
+			if err != nil {
+				return nil, fmt.Errorf("the zone %s declares on %s cannot be read: %w", m.Module, n.Name, err)
+			}
+			z, err := catalogue.ZoneOn(m, layers, published, n.Name, at)
+			if err != nil {
+				return nil, err
+			}
+			zones = append(zones, *z)
+		}
+	}
+	if problems := catalogue.ZonesProblems(zones, overlay.Suffix(), public); len(problems) > 0 {
+		return nil, fmt.Errorf("the mesh's zones cannot be forwarded:\n  - %s", strings.Join(problems, "\n  - "))
+	}
+	return zones, nil
+}
+
 // certificateFor is what the mesh certifies about one machine's internal name.
 //
 // It reaches across two contexts and reads neither one's store from the other: `inventory` knows