[cherry-pick release-1.18] Fast-fail backup when built-in data mover has no running node-agent (#10360)

* Fast-fail backup when built-in data mover has no running node-agent

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Signed-off-by: Joseph <jvaikath@redhat.com>
Signed-off-by: Chai Bot <ship-help-github@redhat.com>

* Run make update to fix import ordering

Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
Signed-off-by: Joseph <jvaikath@redhat.com>
Signed-off-by: Chai Bot <ship-help-github@redhat.com>

* Create new changelog for release 10360

Signed-off-by: Chai Bot <ship-help-github@redhat.com>

---------

Signed-off-by: Joseph <jvaikath@redhat.com>
Signed-off-by: Chai Bot <ship-help-github@redhat.com>
Co-authored-by: Joseph <jvaikath@redhat.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Co-authored-by: Tiger Kaovilai <passawit.kaovilai@gmail.com>

pkg/nodeagent/node_agent.go

@@ -22,6 +22,8 @@ import (
 	"fmt"
 
 	"github.com/cockroachdb/errors"
+	"github.com/sirupsen/logrus"
+	appsv1api "k8s.io/api/apps/v1"
 	corev1api "k8s.io/api/core/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -80,6 +82,34 @@ func KbClientIsRunningInNode(ctx context.Context, namespace string, nodeName str
 	return isRunningInNode(ctx, namespace, nodeName, nil, kubeClient)
 }
 
+// IsReady checks whether the node-agent daemonset has at least one ready pod
+// by inspecting the DaemonSet status. It only checks the daemonset for node
+// OS types that are present in the cluster, following the same pattern as
+// server.checkNodeAgent.
+func IsReady(ctx context.Context, namespace string, crClient ctrlclient.Client, log logrus.FieldLogger) error {
+	if kube.WithLinuxNode(ctx, crClient, log) {
+		ds := new(appsv1api.DaemonSet)
+		if err := crClient.Get(ctx, ctrlclient.ObjectKey{Namespace: namespace, Name: daemonSet}, ds); err != nil {
+			return errors.Wrap(err, "failed to get linux node-agent daemonset")
+		}
+		if ds.Status.NumberReady > 0 {
+			return nil
+		}
+	}
+
+	if kube.WithWindowsNode(ctx, crClient, log) {
+		ds := new(appsv1api.DaemonSet)
+		if err := crClient.Get(ctx, ctrlclient.ObjectKey{Namespace: namespace, Name: daemonsetWindows}, ds); err != nil {
+			return errors.Wrap(err, "failed to get windows node-agent daemonset")
+		}
+		if ds.Status.NumberReady > 0 {
+			return nil
+		}
+	}
+
+	return errors.New("node-agent is not ready: no ready pods found")
+}
+
 // IsRunningInNode checks if the node agent pod is running properly in a specified node through controller client. If not, return the error found
 func IsRunningInNode(ctx context.Context, namespace string, nodeName string, crClient ctrlclient.Client) error {
 	return isRunningInNode(ctx, namespace, nodeName, crClient, nil)