update readme

README.md

@@ -22,6 +22,17 @@ skupper init
 skupper connect --secret /path/to/mysecret.yaml
 ```
 
+By default skupper will try to set itself up to allow connections from
+other skupper sites (using mutual TLS). It uses a LoadBalancer service
+or an OpenShift Route for this. If you don't want this, or your
+cluster is not set up to support those options, you can use the
+`--cluster-local` option to `skupper init` and will then be able only
+accept connections from skupper instances in different namespaces on
+the same cluster.
+
+Note: if using minikube, you can get the LoadBalancer service to setup
+an external ip by running minikube tunnel. (Or else use
+--cluster-local as desrcibed above).