docs: add a step to enable gRPC for the bridge node setup

how-to-guides/bridge-node.md

@@ -137,6 +137,20 @@ celestia bridge start --core.ip validator-1.celestia-{{constants.arabicaChainId}
   --p2p.network arabica --core.port 9090
 ```
 
+:::tip gRPC Configuration for Localhost Connections
+If you're connecting your bridge node to a localhost consensus node (`--core.ip localhost` or `--core.ip 127.0.0.1`), ensure that gRPC is enabled in your consensus node's `app.toml` configuration file. Look for the `[grpc]` section and verify that `enable = true` is set:
+
+```toml
+[grpc]
+# Enable defines if the gRPC server should be enabled.
+enable = true
+# Address defines the gRPC server address to bind to.
+address = "localhost:9090"
+```
+
+Without proper gRPC configuration, the bridge node will not be able to connect to the consensus node.
+:::
+
 You can create your key for your node by [following the `cel-key` instructions](/tutorials/celestia-node-key.md).
 
 Once you start the bridge node, a wallet key will be generated for you.

how-to-guides/consensus-node.md

@@ -430,6 +430,10 @@ You can configure your consensus node to be a public RPC endpoint.
 This allows it to accept connections from data availability nodes and
 serve requests for the data availability API.
 
+:::tip Bridge Node Connectivity
+If you're running a [bridge node](/how-to-guides/bridge-node.md) that connects to your consensus node, ensure that gRPC is properly configured in your `app.toml` file. Bridge nodes require gRPC access (typically on port 9090) to communicate with the consensus layer.
+:::
+
 #### Expose RPC
 
 By default, the RPC service listens on `localhost` which means it can't

how-to-guides/validator-node.md

@@ -59,6 +59,11 @@ celestia bridge init --core.ip <URI> --core.port <port>
 Refer to
 [the ports section of the celestia-node troubleshooting page](/how-to-guides/celestia-node-troubleshooting.md#ports)
 for information on which ports are required to be open on your machine.
+
+When connecting your bridge node to a localhost consensus node, ensure that gRPC
+is properly configured in your consensus node's `app.toml` file. The `[grpc]`
+section should have `enable = true` and the appropriate address setting for the
+bridge node to connect successfully.
 :::
 
 Using an RPC of your own, or one from