From a3dae1f35e5fa3394f10e5b59c3df347bf15cf7f Mon Sep 17 00:00:00 2001
From: Michal Kuratczyk <michal.kuratczyk@broadcom.com>
Date: Thu, 9 Jan 2025 14:31:26 +0100
Subject: [PATCH] Handle no available nodes to cluster with

This came up when testing whether all nodes would wait for node 0
could not start. To test this, I was killing node 0 every few seconds,
so it would attempt to start and then get killed. This led to other
nodes sometimes discovering it and attempting to sync, but then crashing
with function_clause as it went away.
---
 deps/rabbit/src/rabbit_peer_discovery.erl | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/deps/rabbit/src/rabbit_peer_discovery.erl b/deps/rabbit/src/rabbit_peer_discovery.erl
index 56400d3569e..0b196873c05 100644
--- a/deps/rabbit/src/rabbit_peer_discovery.erl
+++ b/deps/rabbit/src/rabbit_peer_discovery.erl
@@ -835,6 +835,12 @@ can_use_discovered_nodes(_DiscoveredNodes, []) ->
 %%
 %% @private
 
+select_node_to_join([]) ->
+    ?LOG_INFO(
+       "Peer discovery: no nodes available for auto-clustering; waiting before retrying...",
+       [],
+       #{domain => ?RMQLOG_DOMAIN_PEER_DISC}),
+    false;
 select_node_to_join([{Node, _Members, _StartTime, _IsReady} | _])
   when Node =:= node() ->
     ?LOG_INFO(