address comments

internal/clients/manager.go

@@ -188,12 +188,12 @@ func (c *AdminAPIClientsManager) GatewayClientsToConfigure() []*adminapi.Client
 	c.lock.RLock()
 	defer c.lock.RUnlock()
 	readyGatewayClients := lo.Values(c.readyGatewayClients)
-	// With dbless mode, we should send configuration to ALL Kong gateway instances.
+	// With DB-less mode, we should send the configuration to ALL gateway instances.
 	if dataplaneutil.IsDBLessMode(c.dbMode) {
 		return readyGatewayClients
 	}
-	// When Kong gateway is DB backed, we return a random admin API client
-	// since KIC only need to send requests to one instance.
+	// When a gateway is DB-backed, we return a random client
+	// since KIC only needs to send requests to one instance.
 	// If there are no ready gateway clients, we return an empty list.
 	if len(readyGatewayClients) == 0 {
 		return []*adminapi.Client{}

internal/clients/manager_test.go

@@ -222,7 +222,6 @@ func TestAdminAPIClientsManager_Clients_DBMode(t *testing.T) {
 		context.Background(),
 		zapr.NewLogger(zap.NewNop()),
 		initialClients,
-
 		&mockReadinessChecker{},
 	)
 	require.NoError(t, err)
@@ -252,7 +251,6 @@ func TestAdminAPIClientsManager_SubscribeToGatewayClientsChanges(t *testing.T) {
 		ctx,
 		zapr.NewLogger(zap.NewNop()),
 		[]*adminapi.Client{testClient},
-
 		readinessChecker)
 
 	require.NoError(t, err)
@@ -472,7 +470,6 @@ func TestAdminAPIClientsManager_PeriodicReadinessReconciliation(t *testing.T) {
 		ctx,
 		zapr.NewLogger(zap.NewNop()),
 		[]*adminapi.Client{testClient},
-
 		readinessChecker,
 		clients.WithReadinessReconciliationTicker(readinessTicker),
 	)

internal/dataplane/kong_client.go

@@ -474,9 +474,10 @@ func (c *KongClient) sendOutToGatewayClients(
 		return nil, err
 	}
 
-	// After succeeded to update configurations in DB mode, we should propagate the SHA from
-	// the chosen gateway client to other clients.
-	if !dataplaneutil.IsDBLessMode(c.dbmode) && len(shas) > 0 {
+	// After a successful configuration update in DB mode, we should propagate the SHA from
+	// the chosen client to other clients as well as they will pick the configuration from the shared database.
+	if !dataplaneutil.IsDBLessMode(c.dbmode) &&
+		len(gatewayClients) > 1 {
 		for _, client := range gatewayClients {
 			client.SetLastConfigSHA([]byte(shas[0]))
 		}