diff --git a/metropolis/test/launch/cluster/cluster.go b/metropolis/test/launch/cluster/cluster.go
index c433780..0efd08b 100644
--- a/metropolis/test/launch/cluster/cluster.go
+++ b/metropolis/test/launch/cluster/cluster.go
@@ -18,6 +18,7 @@
 	"os/exec"
 	"path"
 	"path/filepath"
+	"strings"
 	"syscall"
 	"time"
 
@@ -1099,3 +1100,28 @@
 	}
 	return res, nil
 }
+
+func (c *Cluster) AllNodesHealthy(ctx context.Context) error {
+	// Get an authenticated owner client within the cluster.
+	curC, err := c.CuratorClient()
+	if err != nil {
+		return err
+	}
+	mgmt := apb.NewManagementClient(curC)
+	nodes, err := getNodes(ctx, mgmt)
+	if err != nil {
+		return err
+	}
+
+	var unhealthy []string
+	for _, node := range nodes {
+		if node.Health == apb.Node_HEALTHY {
+			continue
+		}
+		unhealthy = append(unhealthy, node.Id)
+	}
+	if len(unhealthy) == 0 {
+		return nil
+	}
+	return fmt.Errorf("nodes unhealthy: %s", strings.Join(unhealthy, ", "))
+}