diff --git a/.vscode/extensions.json b/.vscode/extensions.json
index 7963e9d4..037f20d7 100644
--- a/.vscode/extensions.json
+++ b/.vscode/extensions.json
@@ -1,6 +1,6 @@
 {
     "recommendations": [
-        "matklad.rust-analyzer",
+        "rust-lang.rust-analyzer",
         "bungcip.better-toml",
         "ms-azuretools.vscode-docker",
         "eamodio.gitlens",
diff --git a/DEPLOY.md b/DEPLOY.md
index a711cc90..7dc25db5 100644
--- a/DEPLOY.md
+++ b/DEPLOY.md
@@ -58,6 +58,12 @@ In Debian you can use this command to create a Conduit user:
 sudo adduser --system conduit --no-create-home
 ```
 
+## Forwarding ports in the firewall or the router
+
+Conduit uses the ports 443 and 8448 both of which need to be open in the firewall.
+
+If Conduit runs behind a router or in a container and has a different public IP address than the host system these public ports need to be forwarded directly or indirectly to the port mentioned in the config.
+
 ## Setting up a systemd service
 
 Now we'll set up a systemd service for Conduit, so it's easy to start/stop Conduit and set it to autostart when your
@@ -247,7 +253,8 @@ $ curl https://your.server.name/_matrix/client/versions
 $ curl https://your.server.name:8448/_matrix/client/versions
 ```
 
-- To check if your server can talk with other homeservers, you can use the [Matrix Federation Tester](https://federationtester.matrix.org/)
+- To check if your server can talk with other homeservers, you can use the [Matrix Federation Tester](https://federationtester.matrix.org/).
+  If you can register but cannot join federated rooms check your config again and also check if the port 8448 is open and forwarded correctly.
 
 # What's next?