From b6dfc2175fcfa02d6fcc5a00928dd9118248cb35 Mon Sep 17 00:00:00 2001
From: Pasha Sviderski <me@psviderski.name>
Date: Fri, 7 Nov 2025 11:18:53 +1000
Subject: [PATCH] fix: reconfigure WireGuard peers when listed >=1 machines in
 cluster store (fixes #155)

---
 internal/machine/cluster.go                 | 8 ++++++++
 internal/machine/machine.go                 | 9 ++++++++-
 internal/machine/network/wireguard_linux.go | 2 +-
 website/docs/1-overview.md                  | 2 +-
 4 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/internal/machine/cluster.go b/internal/machine/cluster.go
index ea14bdfe..adfe7c91 100644
--- a/internal/machine/cluster.go
+++ b/internal/machine/cluster.go
@@ -358,6 +358,14 @@ func (cc *clusterController) handleMachineChanges(ctx context.Context) error {
 					slog.Error("Failed to list machines.", "err", err)
 					continue
 				}
+				// Skip reconfiguration if the machines list is empty. This can happen when joining the cluster.
+				// Corrosion can notifies about table changes before the data is fully replicated.
+				// Reconfiguring with an empty list would remove all peers and lock this machine out of the cluster.
+				// See https://github.com/psviderski/uncloud/issues/155.
+				if len(machines) == 0 {
+					slog.Debug("Skipping peer reconfiguration: machines list in store is empty.")
+					continue
+				}
 				if err = cc.configurePeers(machines); err != nil {
 					slog.Error("Failed to configure peers.", "err", err)
 				}
diff --git a/internal/machine/machine.go b/internal/machine/machine.go
index e5d55f62..a2d1749b 100644
--- a/internal/machine/machine.go
+++ b/internal/machine/machine.go
@@ -821,7 +821,14 @@ func (m *Machine) JoinCluster(_ context.Context, req *pb.JoinClusterRequest) (*e
 	if err := m.state.Save(); err != nil {
 		return nil, status.Errorf(codes.Internal, "save machine state: %v", err)
 	}
-	slog.Info("Machine configured to join the cluster.", "id", m.state.ID, "name", m.state.Name)
+	slog.Info(
+		"Machine configured to join the cluster.",
+		"id", m.state.ID,
+		"name", m.state.Name,
+		"subnet", m.state.Network.Subnet.String(),
+		"management_ip", m.state.Network.ManagementIP.String(),
+		"peers", len(m.state.Network.Peers),
+	)
 	// Signal that the machine is initialised as a member of a cluster.
 	m.initialised <- struct{}{}
 
diff --git a/internal/machine/network/wireguard_linux.go b/internal/machine/network/wireguard_linux.go
index 75fe6107..99ea4bb9 100644
--- a/internal/machine/network/wireguard_linux.go
+++ b/internal/machine/network/wireguard_linux.go
@@ -79,7 +79,7 @@ func (n *WireGuardNetwork) Configure(config Config) error {
 	if err := n.configureDevice(config); err != nil {
 		return err
 	}
-	slog.Info("Configured WireGuard interface.", "name", n.link.Attrs().Name)
+	slog.Info("Configured WireGuard interface.", "name", n.link.Attrs().Name, "peers", len(n.peers))
 
 	managementPrefix, err := addrToSingleIPPrefix(config.ManagementIP)
 	if err != nil {
diff --git a/website/docs/1-overview.md b/website/docs/1-overview.md
index cc0338c7..be5025ec 100644
--- a/website/docs/1-overview.md
+++ b/website/docs/1-overview.md
@@ -42,7 +42,7 @@ Some of the common use cases Uncloud is a great fit for:
 - **Dev/staging environments**: Spin up additional environments for development and testing that mirror production
   reusing the same Compose configuration.
 
-## What makes Uncloud different
+## What makes Uncloud special
 
 Here are the design decisions that make Uncloud stand out: