diff --git a/metropolis/test/e2e/BUILD.bazel b/metropolis/test/e2e/BUILD.bazel
index 8853554..3db8a33 100644
--- a/metropolis/test/e2e/BUILD.bazel
+++ b/metropolis/test/e2e/BUILD.bazel
@@ -27,8 +27,6 @@
         "//third_party/edk2:firmware",
     ],
     embed = [":e2e"],
-    # TODO: https://github.com/monogon-dev/monogon/issues/170
-    flaky = True,
     rundir = ".",
     deps = [
         "//metropolis/node",
diff --git a/metropolis/test/e2e/main_test.go b/metropolis/test/e2e/main_test.go
index b57f3d3..7a72db2 100644
--- a/metropolis/test/e2e/main_test.go
+++ b/metropolis/test/e2e/main_test.go
@@ -20,7 +20,6 @@
 	"context"
 	"errors"
 	"fmt"
-	"io"
 	"net"
 	"net/http"
 	_ "net/http"
@@ -144,6 +143,7 @@
 				}
 				return nil
 			})
+			util.TestEventual(t, "Heartbeat test successful", ctx, 20*time.Second, cluster.AllNodesHealthy)
 			util.TestEventual(t, "Node rejoin successful", ctx, 60*time.Second, func(ctx context.Context) error {
 				// Ensure nodes rejoin the cluster after a reboot by reboting the 1st node.
 				if err := cluster.RebootNode(ctx, 1); err != nil {
@@ -151,40 +151,7 @@
 				}
 				return nil
 			})
-			util.TestEventual(t, "Heartbeat test successful", ctx, 60*time.Second, func(ctx context.Context) error {
-				// Ensure all cluster nodes are capable of sending heartbeat updates.
-				// This test assumes the expected count of nodes is already present in
-				// the cluster.
-				for {
-					srvN, err := mgmt.GetNodes(ctx, &apb.GetNodesRequest{})
-					if err != nil {
-						return fmt.Errorf("GetNodes: %w", err)
-					}
-
-					// Count the unhealthy nodes.
-					var unhealthy int
-					for {
-						node, err := srvN.Recv()
-						if err == io.EOF {
-							break
-						}
-						if err != nil {
-							return fmt.Errorf("GetNodes.Recv: %w", err)
-						}
-
-						if node.Health != apb.Node_HEALTHY {
-							unhealthy++
-						}
-					}
-
-					// If all nodes tested in this iteration are healthy, the test has
-					// been passed.
-					if unhealthy == 0 {
-						break
-					}
-				}
-				return nil
-			})
+			util.TestEventual(t, "Heartbeat test successful", ctx, 20*time.Second, cluster.AllNodesHealthy)
 		})
 		t.Run("Kubernetes", func(t *testing.T) {
 			t.Parallel()
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, ", "))
+}