diff --git a/README.md b/README.md
index 9a9b59d3b..b6c18060a 100644
--- a/README.md
+++ b/README.md
@@ -41,7 +41,8 @@ A web dashboard for running and moderating a server, started and supervised by m
   system logs with downloadable log bundles, crash dumps, a live **Network** page (a draggable flow diagram of the
   traffic between clients and every server, grouped per zone, with each connected player or address; addresses behind a
   permission; opening a group lists its members in the box with a filter, and web clients are named by their signed-in
-  user or API key), a **Performance** page (frame times, time per main-loop phase, slow-frame captures naming what took
+  user or API key; each server box shows its port, and servers on several machines are framed per machine with the
+  links between machines marked), a **Performance** page (frame times, time per main-loop phase, slow-frame captures naming what took
   the time, and profiling sessions with a flame graph), and each server's build identifier on the About page.
 * **Game text from the client:** zone, item and other game names and labels come from the client's locale, in the
   viewer's language (picker in the user menu, or the browser's language), never written into the pages.
diff --git a/docs/Dashboard.md b/docs/Dashboard.md
index ae4becddd..2fc88327e 100644
--- a/docs/Dashboard.md
+++ b/docs/Dashboard.md
@@ -768,6 +768,26 @@ seconds while reports arrive), stops drawing while the tab is hidden. **Diagram*
 per browser. Drag boxes to rearrange the diagram; links leave from the sides that face each other, and **Reset layout**
 puts everything back.
 
+Each server box shows the port it listens on ("Auth :1001"; the dashboard and the UGC server their web port; a zone
+its instance's port while it has one), and an open zone's instance rows show theirs. The ports and each server's
+machine come from master's server list, which the dashboard asks for every 30 seconds and master sends when a server
+comes or goes: master keeps the address and port each server reported when it connected, and its machine is the
+address master sees that connection come from (servers connecting over loopback or from master's `external_ip`, and
+worlds that haven't connected yet, are on master's machine, named by master's `external_ip`). Hover a box, open its
+details or use the List view to see its machine. Player rows and the Connections table show remote ports with
+`network_ips` only, like the addresses.
+
+**Several machines.** When the servers run on more than one machine, the boxes of columns 2 to 5 (auth and the
+worlds, chat, master, the dashboard and UGC) are grouped by machine: each machine's boxes are a band of their own,
+master's machine first and the others under it, each framed with the machine's name, its servers, connections and
+bytes per second. A zone with instances on several machines is a box on each. ▾ on a frame folds the machine into one
+box (its links go to that box, the ones inside it are gone; ▸ on the box shows its servers again); folded machines are
+remembered per browser. Links between two machines are dash-dotted with a ◇ half way, and their tooltip names both
+machines. The game and web clients stay on the sides, centred on all the bands. A dragged box takes its frame along.
+With one machine nothing is framed and the page looks as before. Machines are named by a token without
+`network_ips` (the summary sent to every open page has only tokens; `/api/diagnostics/network/connections` maps
+them to addresses in `hosts` for viewers with the permission).
+
 Game clients, Web clients and a zone with more than one instance are groups: ▸ on the box (or a double click) opens it
 in place. The box grows into a list of its members, one row each (players, and HTTP clients of the UGC server only,
 under Game clients; one row per address and signed-in dashboard account under Web clients; each instance of a zone),
@@ -805,10 +825,12 @@ they are shown only with `network_ips` (Network addresses, level 9 by default; g
 are otherwise replaced by a token that stays the same for the same address until the dashboard restarts. They are kept
 in memory from the last report only and never written to the database.
 
-- `GET /api/diagnostics/network`: the live summary (what the `traffic` topic sends).
+- `GET /api/diagnostics/network`: the live summary (what the `traffic` topic sends), with each server's listening
+  `port` and its machine as a `host` token (both null until master's server list names the server).
 - `GET /api/diagnostics/network/server?key=world:1200:3`: one server's details.
-- `GET /api/diagnostics/network/connections`: the connection list (addresses with `network_ips`; `user` and
-  `account_id` on web clients that were signed in).
+- `GET /api/diagnostics/network/connections`: the connection list (addresses and remote ports with `network_ips`;
+  `user` and `account_id` on web clients that were signed in; `hosts`, each machine token to its address, with
+  `network_ips` only).
 
 **Prometheus**: `/metrics` has the same counters, totals since the dashboard started: `darkflame_net_packets_total`,
 `darkflame_net_bytes_total` and `darkflame_net_datagrams_total` (labels `server`, `direction`),