to-be 08: the found tunnel's configuration is retired once the take is proven (ADR 0119)

03-DESIGN/01-to-be/08-connectivity.md

@@ -7,11 +7,12 @@ code:
   - mesh-controller internal/identity/authority.go
   - mesh-host internal/identity/serving.go
   - mesh-host internal/apply (the service that reflects a rule set)
-updated: 2026-09-25
+updated: 2026-09-27
 decisions:
   - 02-DECISIONS/0104-a-provision-may-be-answered-by-an-adapter-to-the-predecessor.md
   - 02-DECISIONS/0106-the-bus-is-nats.md
   - 02-DECISIONS/0105-the-mesh-adopts-the-predecessors-tunnel-in-place.md
+  - 02-DECISIONS/0119-a-taken-tunnels-predecessor-is-retired.md
   - 02-DECISIONS/0108-a-route-carries-the-policy-applied-to-a-request.md
   - 02-DECISIONS/0103-what-an-adopted-node-holds-and-what-its-guard-refuses.md
   - 02-DECISIONS/0100-a-node-in-use-is-adopted-before-it-is-converged.md
@@ -768,6 +769,12 @@ where a found tunnel is left running beside the mesh's; where it is adopted ther
 The guard admits the mesh's ports from that one interface, and the predecessor's peers arrive on
 it.
 
+*2026-09-27, [ADR 0119](../../02-DECISIONS/0119-a-taken-tunnels-predecessor-is-retired.md).* The
+found configuration is kept only until the take is proven — the found unit down, the mesh's
+interface up and handshaking with a peer. Then it is removed from where the found unit reads it
+(its original stays kept), the hold ends, and the predecessor's tunnel cannot be raised again by
+anything but a person restoring it by hand. Undeclaring the private network does not bring it back.
+
 ## The bus is NATS
 
 *2026-09-23, [ADR 0106](../../02-DECISIONS/0106-the-bus-is-nats.md). Architecture to be written