Limit the number of outbound connections to MaxConnections

This commit also fixes control channel shenanigans:
- recover error in control channel accept

network/default.go

@@ -29,6 +29,8 @@ var (
 	ControlChannel = "control"
 	// DefaultLink is default network link
 	DefaultLink = "network"
+	// MaxCconnections is the max number of network client connections
+	MaxCconnections = 3
 )
 
 var (
@@ -193,6 +195,15 @@ func (n *network) resolveNodes() ([]string, error) {
 		}
 	}
 
+	// only return MaxCconnections nodes
+	if len(nodes) > MaxCconnections {
+		resNodes := make([]string, MaxCconnections)
+		for i, _ := range resNodes {
+			resNodes[i] = nodes[i]
+		}
+		return resNodes, nil
+	}
+
 	return nodes, nil
 }
 
@@ -497,7 +508,6 @@ func (n *network) handleCtrlConn(sess tunnel.Session, msg chan *transport.Messag
 	for {
 		m := new(transport.Message)
 		if err := sess.Recv(m); err != nil {
-			// TODO: should we bail here?
 			log.Debugf("Network tunnel advert receive error: %v", err)
 			return
 		}
@@ -516,9 +526,7 @@ func (n *network) acceptCtrlConn(l tunnel.Listener, recv chan *transport.Message
 		// accept a connection
 		conn, err := l.Accept()
 		if err != nil {
-			// TODO: handle this
 			log.Debugf("Network tunnel [%s] accept error: %v", ControlChannel, err)
-			return
 		}
 
 		select {