@@ -183,7 +183,7 @@ func (r *controller) Start(ctx context.Context) error {

 	for {

 		if err := r.adapter.start(ctx); err != nil {

-			if _, ok := err.(libnetwork.ErrNoSuchNetwork); ok {

+			if _, ok := errors.Cause(err).(libnetwork.ErrNoSuchNetwork); ok {

 				// Retry network creation again if we

 				// failed because some of the networks

 				// were not found.

@@ -7,6 +7,7 @@ import (

 	"runtime"

 	"testing"

+	"github.com/docker/docker/api/errdefs"

 	containertypes "github.com/docker/docker/api/types/container"

 	"github.com/docker/docker/container"

 	_ "github.com/docker/docker/pkg/discovery/memory"

@@ -17,6 +18,8 @@ import (

 	"github.com/docker/docker/volume/local"

 	"github.com/docker/docker/volume/store"

 	"github.com/docker/go-connections/nat"

+	"github.com/docker/libnetwork"

+	"github.com/pkg/errors"

 	"github.com/stretchr/testify/assert"

 )

@@ -311,3 +314,12 @@ func TestValidateContainerIsolation(t *testing.T) {

 	_, err := d.verifyContainerSettings(runtime.GOOS, &containertypes.HostConfig{Isolation: containertypes.Isolation("invalid")}, nil, false)

 	assert.EqualError(t, err, "invalid isolation 'invalid' on "+runtime.GOOS)

 }

+

+func TestFindNetworkErrorType(t *testing.T) {

+	d := Daemon{}

+	_, err := d.FindNetwork("fakeNet")

+	_, ok := errors.Cause(err).(libnetwork.ErrNoSuchNetwork)

+	if !errdefs.IsNotFound(err) || !ok {

+		assert.Fail(t, "The FindNetwork method MUST always return an error that implements the NotFound interface and is ErrNoSuchNetwork")

+	}

+}

@@ -21,10 +21,6 @@ func volumeNotFound(id string) error {

 	return objNotFoundError{"volume", id}

 }

-func networkNotFound(id string) error {

-	return objNotFoundError{"network", id}

-}

-

 type objNotFoundError struct {

 	object string

 	id     string

@@ -230,3 +226,20 @@ func translateContainerdStartErr(cmd string, setExitCode func(int), err error) e

 	// TODO: it would be nice to get some better errors from containerd so we can return better errors here

 	return retErr

 }

+

+// TODO: cpuguy83 take care of it once the new library is ready

+type errNotFound struct{ error }

+

+func (errNotFound) NotFound() {}

+

+func (e errNotFound) Cause() error {

+	return e.error

+}

+

+// notFound is a helper to create an error of the class with the same name from any error type

+func notFound(err error) error {

+	if err == nil {

+		return nil

+	}

+	return errNotFound{err}

+}

@@ -45,7 +45,9 @@ func (daemon *Daemon) FindNetwork(idName string) (libnetwork.Network, error) {

 	// 3. match by ID prefix

 	list := daemon.GetNetworksByIDPrefix(idName)

 	if len(list) == 0 {

-		return nil, errors.WithStack(networkNotFound(idName))

+		// Be very careful to change the error type here, the libnetwork.ErrNoSuchNetwork error is used by the controller

+		// to retry the creation of the network as managed through the swarm manager

+		return nil, errors.WithStack(notFound(libnetwork.ErrNoSuchNetwork(idName)))

 	}

 	if len(list) > 1 {

 		return nil, errors.WithStack(invalidIdentifier(idName))

@@ -49,7 +49,7 @@ func (s *DockerSuite) TestNetHostname(c *check.C) {

 	c.Assert(out, checker.Contains, "Invalid network mode: invalid container format container:<name|id>")

 	out, _ = dockerCmdWithFail(c, "run", "--net=weird", "busybox", "ps")

-	c.Assert(strings.ToLower(out), checker.Contains, "no such network")

+	c.Assert(strings.ToLower(out), checker.Contains, "not found")

 }

 func (s *DockerSuite) TestConflictContainerNetworkAndLinks(c *check.C) {