diff --git a/docker-compose.yml b/docker-compose.yml
index 7011213..0d2d5d9 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -10,7 +10,11 @@ services:
   remote-control-support:
     image: ${IMAGE:-git.mancinas.io/rmancinas/remote-control-support-webapp:latest}
     ports:
-      - "8091:8080"
+      # 8091 is reserved on the Swarm ingress by ai-training-lab_ai-lab, and a
+      # reservation holds even when nothing is answering on it — so this sits
+      # well clear of the 809x block. 5910 is VNC display :10, which is at least
+      # a hint about what is listening.
+      - "5910:8080"
     environment:
       DB_PATH: /data/rcs.db
       TRUST_PROXY: "true"