Wait for userdocker to start

cmd/wait/wait.go

@@ -0,0 +1,19 @@
+package wait
+
+import (
+	"os"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/rancherio/os/config"
+	"github.com/rancherio/os/docker"
+)
+
+func Main() {
+	_, err := docker.NewClient(config.DOCKER_HOST)
+	if err != nil {
+		logrus.Errorf("Failed to conect to Docker")
+		os.Exit(1)
+	}
+
+	logrus.Infof("Docker is ready")
+}

config/default.go

@@ -129,6 +129,7 @@ func NewConfig() *Config {
 					"/init:/usr/bin/rancherctl:ro",
 					"/init:/usr/bin/respawn:ro",
 					"/init:/usr/bin/system-docker:ro",
+					"/init:/usr/sbin/wait-for-docker:ro",
 					"/lib/modules:/lib/modules:ro",
 					"/usr/bin/docker:/usr/bin/docker:ro",
 				},
@@ -255,6 +256,15 @@ func NewConfig() *Config {
 				Links: []string{
 					"network",
 				},
+			"userdockerwait": {
+				Image: "userdockerwait",
+				Net:   "host",
+				Labels: []string{
+					"io.rancher.os.detach=false",
+				},
+				Links: []string{
+					"userdocker",
+				},
 				VolumesFrom: []string{
 					"all-volumes",
 				},

main.go

@@ -8,11 +8,12 @@ import (
 	"github.com/docker/docker/pkg/reexec"
 	"github.com/rancherio/os/cmd/cloudinit"
 	"github.com/rancherio/os/cmd/control"
+	"github.com/rancherio/os/cmd/network"
 	"github.com/rancherio/os/cmd/power"
 	"github.com/rancherio/os/cmd/respawn"
 	"github.com/rancherio/os/cmd/sysinit"
 	"github.com/rancherio/os/cmd/systemdocker"
-	"github.com/rancherio/os/cmd/network"
+	"github.com/rancherio/os/cmd/wait"
 	osInit "github.com/rancherio/os/init"
 )
 
@@ -46,6 +47,7 @@ func main() {
 	registerCmd("/usr/sbin/rancherctl", control.Main)
 	registerCmd("/usr/bin/cloud-init", cloudinit.Main)
 	registerCmd("/usr/sbin/netconf", network.Main)
+	registerCmd("/usr/sbin/wait-for-docker", wait.Main)
 
 	if !reexec.Init() {
 		log.Fatalf("Failed to find an entry point for %s", os.Args[0])

scripts/dockerimages/11-userdockerwait

@@ -0,0 +1,2 @@
+FROM base
+CMD ["/usr/sbin/wait-for-docker"]