diff --git a/beacon_node/src/main.rs b/beacon_node/src/main.rs
index 26537c6f7..69ac6f1bd 100644
--- a/beacon_node/src/main.rs
+++ b/beacon_node/src/main.rs
@@ -252,6 +252,7 @@ fn main() {
                 .arg(Arg::with_name("server")
                     .value_name("HTTP_SERVER")
                     .required(true)
+                    .default_value("http://localhost:5052")
                     .help("A HTTP server, with a http:// prefix"))
                 .arg(Arg::with_name("libp2p-port")
                     .short("p")
diff --git a/book/src/simple-testnet.md b/book/src/simple-testnet.md
index bf41e455d..b6fa19d6f 100644
--- a/book/src/simple-testnet.md
+++ b/book/src/simple-testnet.md
@@ -66,7 +66,7 @@ In a new terminal terminal, run:
 
 
 ```
-$ ./beacon_node -b 10 testnet -r bootstrap http://localhost:5052
+$ ./beacon_node -b 10 testnet -r bootstrap
 ```
 
 > Notes:
@@ -74,7 +74,8 @@ $ ./beacon_node -b 10 testnet -r bootstrap http://localhost:5052
 > - The `-b` (or `--port-bump`) increases all the listening TCP/UDP ports of
 >   the new node to `10` higher. Your first node's HTTP server was at TCP
 >   `5052` but this one will be at `5062`.
-> - The `-r` flag creates a new data directory in your home with a random
->   string appended, to avoid conflicting with any other running node.
-> - The HTTP address is the API of the first node. The new node will download
->   configuration via HTTP before starting sync via libp2p.
+> - The `-r` flag creates a new data directory with a random string appended
+>   (avoids data directory collisions between nodes).
+> - The default bootstrap HTTP address is `http://localhost:5052`. The new node
+>   will download configuration via HTTP before starting sync via libp2p.
+> - See `$ ./beacon_node testnet bootstrap --help` for more configuration.