1 files changed, 18 insertions, 0 deletions
diff --git a/doc/api/dgram.md b/doc/api/dgram.md
index 652e2baadc..38500359f6 100644
--- a/doc/api/dgram.md
+++ b/doc/api/dgram.md
@@ -95,6 +95,24 @@ Tells the kernel to join a multicast group at the given `multicastAddress` and
 one interface and will add membership to it. To add membership to every
 available interface, call `addMembership` multiple times, once per interface.
 
+When sharing a UDP socket across multiple `cluster` workers, the
+`socket.addMembership()` function must be called only once or an
+`EADDRINUSE` error will occur:
+
+```js
+const cluster = require('cluster');
+const dgram = require('dgram');
+if (cluster.isMaster) {
+  cluster.fork(); // Works ok.
+  cluster.fork(); // Fails with EADDRINUSE.
+} else {
+  const s = dgram.createSocket('udp4');
+  s.bind(1234, () => {
+    s.addMembership('224.0.0.114');
+  });
+}
+```
+
 ### socket.address()
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