diff --git a/doc/api/http.md b/doc/api/http.md
index 2a92e60e5b8983..fb035b6fcc996f 100644
--- a/doc/api/http.md
+++ b/doc/api/http.md
@@ -1705,8 +1705,10 @@ setTimeout(() => {
 added: v18.2.0
 -->
 
-Closes all connections connected to this server, including active connections
-connected to this server which are sending a request or waiting for a response.
+Closes all established HTTP(S) connections connected to this server, including
+active connections connected to this server which are sending a request or
+waiting for a response. This does _not_ destroy sockets upgraded to a different
+protocol, such as WebSocket or HTTP/2.
 
 > This is a forceful way of closing all connections and should be used with
 > caution. Whenever using this in conjunction with `server.close`, calling this