Fix: skip not mounted volumes when backing up

Signed-off-by: dkeven <keven@kubesphere.io>

changelogs/unreleased/4497-dkeven

@@ -0,0 +1 @@
+Skip not mounted volumes when backing up

pkg/restic/backupper.go

@@ -25,6 +25,7 @@ import (
 	"github.com/sirupsen/logrus"
 	corev1api "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/util/sets"
 	corev1client "k8s.io/client-go/kubernetes/typed/core/v1"
 	"k8s.io/client-go/tools/cache"
 
@@ -118,9 +119,10 @@ func (b *backupper) BackupPodVolumes(backup *velerov1api.Backup, pod *corev1api.
 	b.resultsLock.Unlock()
 
 	var (
-		errs             []error
-		podVolumeBackups []*velerov1api.PodVolumeBackup
-		podVolumes       = make(map[string]corev1api.Volume)
+		errs              []error
+		podVolumeBackups  []*velerov1api.PodVolumeBackup
+		podVolumes        = make(map[string]corev1api.Volume)
+		mountedPodVolumes = sets.String{}
 	)
 
 	// put the pod's volumes in a map for efficient lookup below
@@ -128,6 +130,12 @@ func (b *backupper) BackupPodVolumes(backup *velerov1api.Backup, pod *corev1api.
 		podVolumes[podVolume.Name] = podVolume
 	}
 
+	for _, container := range pod.Spec.Containers {
+		for _, volumeMount := range container.VolumeMounts {
+			mountedPodVolumes.Insert(volumeMount.Name)
+		}
+	}
+
 	var numVolumeSnapshots int
 	for _, volumeName := range volumesToBackup {
 		volume, ok := podVolumes[volumeName]
@@ -162,6 +170,13 @@ func (b *backupper) BackupPodVolumes(backup *velerov1api.Backup, pod *corev1api.
 			continue
 		}
 
+		// volumes that are not mounted by any container should not be backed up, because
+		// its directory is not created
+		if !mountedPodVolumes.Has(volumeName) {
+			log.Warnf("Volume %s is declared in pod %s/%s but not mounted by any container, skipping", volumeName, pod.Namespace, pod.Name)
+			continue
+		}
+
 		volumeBackup := newPodVolumeBackup(backup, pod, volume, repo.Spec.ResticIdentifier, pvc)
 		if volumeBackup, err = b.repoManager.veleroClient.VeleroV1().PodVolumeBackups(volumeBackup.Namespace).Create(context.TODO(), volumeBackup, metav1.CreateOptions{}); err != nil {
 			errs = append(errs, err)