diff --git a/cmd/uncloud/service/run.go b/cmd/uncloud/service/run.go
index 0f16fe10..b41d5de1 100644
--- a/cmd/uncloud/service/run.go
+++ b/cmd/uncloud/service/run.go
@@ -6,6 +6,7 @@ import (
 	"github.com/spf13/cobra"
 	"uncloud/internal/cli"
 	"uncloud/internal/cli/client"
+	"uncloud/internal/docker"
 )
 
 func NewRunCommand() *cobra.Command {
@@ -31,6 +32,10 @@ func NewRunCommand() *cobra.Command {
 		&opts.Machine, "machine", "m", "",
 		"Name or ID of the machine to run the service on. (default is first available)",
 	)
+	cmd.Flags().StringVar(&opts.Mode, "mode", docker.DeployModeReplicated,
+		fmt.Sprintf("Replication mode of the service: either %q (a specified number of containers across "+
+			"the machines) or %q (one container on every machine).",
+			docker.DeployModeReplicated, docker.DeployModeGlobal))
 	cmd.Flags().StringSliceVarP(&opts.Publish, "publish", "p", nil,
 		"Publish a service port to make it accessible outside the cluster. Can be specified multiple times. "+
 			"Format: [load_balancer_port:]container_port[/protocol]")
diff --git a/internal/cli/client/service.go b/internal/cli/client/service.go
index daabd870..1898ef86 100644
--- a/internal/cli/client/service.go
+++ b/internal/cli/client/service.go
@@ -22,6 +22,8 @@ type ServiceOptions struct {
 	Image   string
 	Name    string
 	Machine string
+	// Mode is the replication mode of the service.
+	Mode    string
 	Publish []string
 }
 
@@ -39,6 +41,14 @@ func (c *Client) RunService(ctx context.Context, opts *ServiceOptions) (RunServi
 		return resp, fmt.Errorf("invalid image: %w", err)
 	}
 
+	switch opts.Mode {
+	case docker.DeployModeReplicated:
+	case docker.DeployModeGlobal:
+		return resp, errors.New("global mode is not supported yet")
+	default:
+		return resp, fmt.Errorf("invalid mode: %q", opts.Mode)
+	}
+
 	// Find a machine to run the service on.
 	listResp, err := c.ListMachines(ctx, &emptypb.Empty{})
 	if err != nil {