log debug lsblk output.

providers/os/connection/snapshot/blockdevices.go

@@ -18,6 +18,10 @@ type BlockDevices struct {
 	BlockDevices []BlockDevice `json:"blockDevices,omitempty"`
 }
 
+type ExcludeFilter struct {
+	ExcludePartLabel string
+}
+
 type BlockDevice struct {
 	Name       string        `json:"name,omitempty"`
 	FsType     string        `json:"fstype,omitempty"`
@@ -26,15 +30,18 @@ type BlockDevice struct {
 	MountPoint string        `json:"mountpoint,omitempty"`
 	Children   []BlockDevice `json:"children,omitempty"`
 	Size       int           `json:"size,omitempty"`
+	PartLabel  string        `json:"partlabel,omitempty"`
 }
 
 type PartitionInfo struct {
 	Name   string
 	FsType string
+	Uuid   string
+	Lvm    bool
 }
 
 func (cmdRunner *LocalCommandRunner) GetBlockDevices() (*BlockDevices, error) {
-	cmd, err := cmdRunner.RunCommand("lsblk -bo NAME,SIZE,FSTYPE,MOUNTPOINT,LABEL,UUID --json")
+	cmd, err := cmdRunner.RunCommand("lsblk -bo NAME,SIZE,FSTYPE,MOUNTPOINT,LABEL,UUID,PARTLABEL --json")
 	if err != nil {
 		return nil, err
 	}
@@ -73,8 +80,9 @@ func (blockEntries BlockDevices) GetRootBlockEntry() (*PartitionInfo, error) {
 	return nil, errors.New("target volume not found on instance")
 }
 
-func (blockEntries BlockDevices) GetBlockEntryByName(name string) (*PartitionInfo, error) {
+func (blockEntries BlockDevices) GetBlockEntryByName(name string, filters *ExcludeFilter) (*PartitionInfo, error) {
 	log.Debug().Str("name", name).Msg("get matching block entry")
+	candidates := []BlockDevice{}
 	var secondName string
 	if strings.HasPrefix(name, "/dev/sd") {
 		// sdh and xvdh are interchangeable
@@ -94,19 +102,36 @@ func (blockEntries BlockDevices) GetBlockEntryByName(name string) (*PartitionInf
 			}
 		}
 		log.Debug().Str("location", d.Name).Msg("found match")
-		// sort the children by size, so we can pick the largest one
-		sort.Slice(d.Children, func(i, j int) bool {
-			return d.Children[i].Size > d.Children[j].Size
-		})
 		for _, entry := range d.Children {
 			log.Debug().Str("name", entry.Name).Int("size", entry.Size).Msg("checking partition")
+			if filters != nil && strings.Contains(entry.PartLabel, filters.ExcludePartLabel) {
+				log.Debug().Str("name", entry.Name).Str("partlabel", entry.PartLabel).Msg("skipping partition, excluded (partlabel)")
+				continue
+			}
+
 			if entry.IsNotBootOrRootVolumeAndUnmounted() {
-				devFsName := "/dev/" + entry.Name
-				return &PartitionInfo{Name: devFsName, FsType: entry.FsType}, nil
+				if entry.IsLvm() {
+					log.Debug().Str("name", entry.Name).Msg("found lvm partition")
+					candidates = append(candidates, entry.Children[0])
+				} else {
+					candidates = append(candidates, entry)
+				}
 			}
 		}
 	}
-	return nil, errors.New("target volume not found on instance")
+
+	if len(candidates) == 0 {
+		return nil, errors.New("target volume not found on instance")
+	}
+
+	// sort the candidates by size, so we can pick the largest one
+	sort.Slice(candidates, func(i, j int) bool {
+		return candidates[i].Size > candidates[j].Size
+	})
+
+	// return the largest partition
+	devFsName := "/dev/" + candidates[0].Name
+	return &PartitionInfo{Name: devFsName, FsType: candidates[0].FsType}, nil
 }
 
 func (blockEntries BlockDevices) GetUnnamedBlockEntry() (*PartitionInfo, error) {
@@ -164,3 +189,9 @@ func (entry BlockDevice) IsRootVolume() bool {
 func (entry BlockDevice) IsNotBootOrRootVolumeAndUnmounted() bool {
 	return entry.IsNoBootVolume() && entry.MountPoint == "" && !entry.IsRootVolume()
 }
+
+func (entry BlockDevice) IsLvm() bool {
+	log.Debug().Interface("part", entry).Msg("checking if lvm")
+
+	return strings.Contains(entry.FsType, "LVM2") && len(entry.Children) > 0
+}

providers/os/connection/snapshot/volumemounter.go

@@ -106,7 +106,7 @@ func (m *VolumeMounter) getFsInfo() (*PartitionInfo, error) {
 		return blockEntries.GetUnnamedBlockEntry()
 	}
 
-	fsInfo, err = blockEntries.GetBlockEntryByName(m.VolumeAttachmentLoc)
+	fsInfo, err = blockEntries.GetBlockEntryByName(m.VolumeAttachmentLoc, nil)
 	if err == nil && fsInfo != nil {
 		return fsInfo, nil
 	} else {
@@ -139,7 +139,7 @@ func (m *VolumeMounter) GetDeviceForMounting(target string) (*PartitionInfo, err
 		// we need to simplify those
 		return blockDevices.GetUnnamedBlockEntry()
 	}
-	return blockDevices.GetBlockEntryByName(target)
+	return blockDevices.GetBlockEntryByName(target, nil)
 }
 
 func (m *VolumeMounter) mountVolume(fsInfo *PartitionInfo) error {