Start DNS server, change logs, add SOA records

command/agent/command.go

@@ -17,7 +17,7 @@ import (
 // gracefulTimeout controls how long we wait before forcefully terminating
 var gracefulTimeout = 5 * time.Second
 
-// Command is a Command implementation that runs a Serf agent.
+// Command is a Command implementation that runs a Consul agent.
 // The command will not end unless a shutdown message is sent on the
 // ShutdownCh. If two messages are sent on the ShutdownCh it will forcibly
 // exit.
@@ -29,6 +29,7 @@ type Command struct {
 	agent      *Agent
 	rpcServer  *AgentRPC
 	httpServer *HTTPServer
+	dnsServer  *DNSServer
 }
 
 // readConfig is responsible for setup of our configuration using
@@ -133,7 +134,7 @@ func (c *Command) setupAgent(config *Config, logOutput io.Writer, logWriter *log
 	}
 
 	// Start the IPC layer
-	c.Ui.Output("Starting Serf agent RPC...")
+	c.Ui.Output("Starting Consul agent RPC...")
 	c.rpcServer = NewAgentRPC(agent, rpcListener, logOutput, logWriter)
 
 	if config.HTTPAddr != "" {
@@ -145,6 +146,17 @@ func (c *Command) setupAgent(config *Config, logOutput io.Writer, logWriter *log
 		}
 		c.httpServer = server
 	}
+
+	if config.DNSAddr != "" {
+		server, err := NewDNSServer(agent, logOutput, config.DNSAddr)
+		if err != nil {
+			agent.Shutdown()
+			c.Ui.Error(fmt.Sprintf("Error starting dns server: %s", err))
+			return err
+		}
+		c.dnsServer = server
+	}
+
 	return nil
 }
 
@@ -188,6 +200,7 @@ func (c *Command) Run(args []string) int {
 	c.Ui.Info(fmt.Sprintf("Advertise addr: '%s'", config.AdvertiseAddr))
 	c.Ui.Info(fmt.Sprintf("      RPC addr: '%s'", config.RPCAddr))
 	c.Ui.Info(fmt.Sprintf("     HTTP addr: '%s'", config.HTTPAddr))
+	c.Ui.Info(fmt.Sprintf("      DNS addr: '%s'", config.DNSAddr))
 	c.Ui.Info(fmt.Sprintf("     Encrypted: %#v", config.EncryptKey != ""))
 	c.Ui.Info(fmt.Sprintf("        Server: %v (bootstrap: %v)", config.Server, config.Bootstrap))
 

command/agent/dns.go

@@ -44,7 +44,6 @@ func NewDNSServer(agent *Agent, logOutput io.Writer, bind string) (*DNSServer, e
 	// Async start the DNS Server, handle a potential error
 	errCh := make(chan error, 1)
 	go func() {
-		srv.logger.Printf("[INFO] dns: starting server at %v", bind)
 		err := server.ListenAndServe()
 		srv.logger.Printf("[ERR] dns: error starting server: %v", err)
 		errCh <- err
@@ -67,7 +66,6 @@ func NewDNSServer(agent *Agent, logOutput io.Writer, bind string) (*DNSServer, e
 			return
 		}
 
-		srv.logger.Printf("resp %#v", in)
 		if len(in.Answer) == 0 {
 			checkCh <- fmt.Errorf("no response to test message")
 			return
@@ -99,8 +97,30 @@ func (d *DNSServer) handleConsul(resp dns.ResponseWriter, req *dns.Msg) {
 	// Always respond with TXT "ok"
 	m := new(dns.Msg)
 	m.SetReply(req)
+	m.Authoritative = true
 	header := dns.RR_Header{Name: q.Name, Rrtype: dns.TypeTXT, Class: dns.ClassINET, Ttl: 0}
 	txt := &dns.TXT{header, []string{"ok"}}
 	m.Answer = append(m.Answer, txt)
+	d.addSOA("consul.", m)
 	resp.WriteMsg(m)
 }
+
+// addSOA is used to add an SOA record to a message for the given domain
+func (d *DNSServer) addSOA(domain string, msg *dns.Msg) {
+	soa := &dns.SOA{
+		Hdr: dns.RR_Header{
+			Name:   domain,
+			Rrtype: dns.TypeSOA,
+			Class:  dns.ClassINET,
+			Ttl:    0,
+		},
+		Ns:      "ns." + domain,
+		Mbox:    "postmaster." + domain,
+		Serial:  uint32(time.Now().Unix()),
+		Refresh: 3600,
+		Retry:   600,
+		Expire:  86400,
+		Minttl:  0,
+	}
+	msg.Ns = append(msg.Ns, soa)
+}