diff --git a/cli/command/stack/deploy_composefile.go b/cli/command/stack/deploy_composefile.go
index abe0b0ea2c..1b2ca1d6f0 100644
--- a/cli/command/stack/deploy_composefile.go
+++ b/cli/command/stack/deploy_composefile.go
@@ -13,6 +13,7 @@ import (
 	"github.com/docker/cli/cli/compose/loader"
 	composetypes "github.com/docker/cli/cli/compose/types"
 	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/container"
 	"github.com/docker/docker/api/types/swarm"
 	apiclient "github.com/docker/docker/client"
 	dockerclient "github.com/docker/docker/client"
@@ -177,11 +178,11 @@ func validateExternalNetworks(
 		network, err := client.NetworkInspect(ctx, networkName, false)
 		if err != nil {
 			if dockerclient.IsErrNetworkNotFound(err) {
-				return errors.Errorf("network %q is declared as external, but could not be found. You need to create the network before the stack is deployed (with overlay driver)", networkName)
+				return errors.Errorf("network %q is declared as external, but could not be found. You need to create a swarm-scoped network before the stack is deployed", networkName)
 			}
 			return err
 		}
-		if network.Scope != "swarm" {
+		if container.NetworkMode(networkName).IsUserDefined() && network.Scope != "swarm" {
 			return errors.Errorf("network %q is declared as external, but it is not in the right scope: %q instead of %q", networkName, network.Scope, "swarm")
 		}
 	}
diff --git a/cli/compose/convert/service.go b/cli/compose/convert/service.go
index 79c6555276..8b0dd311e0 100644
--- a/cli/compose/convert/service.go
+++ b/cli/compose/convert/service.go
@@ -214,18 +214,21 @@ func convertServiceNetworks(
 		if !ok && networkName != defaultNetwork {
 			return nil, errors.Errorf("undefined network %q", networkName)
 		}
-		var aliases []string
-		if network != nil {
-			aliases = network.Aliases
-		}
 		target := namespace.Scope(networkName)
 		if networkConfig.External.External {
 			target = networkConfig.External.Name
 		}
-		nets = append(nets, swarm.NetworkAttachmentConfig{
-			Target:  target,
-			Aliases: append(aliases, name),
-		})
+		netAttachConfig := swarm.NetworkAttachmentConfig{
+			Target: target,
+		}
+		if container.NetworkMode(target).IsUserDefined() {
+			var aliases []string
+			if network != nil {
+				aliases = network.Aliases
+			}
+			netAttachConfig.Aliases = append(aliases, name)
+		}
+		nets = append(nets, netAttachConfig)
 	}
 
 	sort.Sort(byNetworkTarget(nets))