diff --git a/docs/development/plugin-triggers.md b/docs/development/plugin-triggers.md
index 660b0696e..2e82717fa 100644
--- a/docs/development/plugin-triggers.md
+++ b/docs/development/plugin-triggers.md
@@ -738,7 +738,7 @@ set -eo pipefail; [[ $DOKKU_TRACE ]] && set -x
 
 - Description: Computes the ports for a given app container
 - Invoked by: `internally triggered by proxy-build-config within proxy implementations`
-- Arguments: `$APP`
+- Arguments: `$APP $PROC_TYPE $IS_HEROKUISH_CONTAINER $CONTAINER_INDEX`
 - Example:
 
 ```shell
diff --git a/plugins/scheduler-docker-local/scheduler-deploy b/plugins/scheduler-docker-local/scheduler-deploy
index 6f4c7c0f5..581a3f534 100755
--- a/plugins/scheduler-docker-local/scheduler-deploy
+++ b/plugins/scheduler-docker-local/scheduler-deploy
@@ -86,7 +86,7 @@ trigger-scheduler-docker-local-scheduler-deploy() {
       [[ -n "$DOKKU_START_CMD" ]] && START_CMD="$DOKKU_START_CMD"
 
       if [[ "$PROC_TYPE" == "web" ]]; then
-        ports=($(plugn trigger network-compute-ports "$APP" "$PROC_TYPE" "$DOKKU_HEROKUISH"))
+        ports=($(plugn trigger network-compute-ports "$APP" "$PROC_TYPE" "$DOKKU_HEROKUISH" "$CONTAINER_INDEX"))
         local DOKKU_DOCKER_PORT_ARGS=""
         local DOKKU_PORT=""
         for p in "${ports[@]}"; do