communicator/ssh: retry connection in ConnectFunc forawhile

communicator/ssh/connect.go

@@ -1,6 +1,7 @@
 package ssh
 
 import (
+	"errors"
 	"log"
 	"net"
 	"time"
@@ -11,7 +12,22 @@ import (
 // is suitable for use with the SSH communicator configuration.
 func ConnectFunc(network, addr string) func() (net.Conn, error) {
 	return func() (net.Conn, error) {
-		log.Printf("Opening conn for SSH to %s %s", network, addr)
-		return net.DialTimeout(network, addr, 15*time.Second)
+		timeout := time.After(5 * time.Minute)
+
+		for {
+			select {
+			case <-timeout:
+				return nil, errors.New("timeout connecting to remote machine")
+			default:
+			}
+
+			log.Printf("Opening conn for SSH to %s %s", network, addr)
+			nc, err := net.DialTimeout(network, addr, 15*time.Second)
+			if err == nil {
+				return nc, nil
+			}
+
+			time.Sleep(500 * time.Millisecond)
+		}
 	}
 }