lxd/storage/backend_lxd: Set the volume's UUID at the right place for…

… instance migration

Signed-off-by: Julian Pelizäus <[email protected]>

lxd/storage/backend_lxd.go

@@ -1964,7 +1964,13 @@ func (b *lxdBackend) CreateInstanceFromMigration(inst instance.Instance, conn io
 	} else if srcInfo != nil && srcInfo.Config != nil && srcInfo.Config.Volume != nil {
 		volumeConfig = srcInfo.Config.Volume.Config
 		volumeDescription = srcInfo.Config.Volume.Description
+
+		// Override the source volume's UUID.
+		// Do this before asking the storage driver if it has the volume.
+		// Some storage drivers might require the UUID to generate the volume name.
+		volumeConfig["volatile.uuid"] = uuid.New().String()
 	} else {
+		// A new UUID gets created during creation of the record in the DB.
 		volumeConfig = make(map[string]string)
 		volumeDescription = args.Description
 	}
@@ -2017,12 +2023,9 @@ func (b *lxdBackend) CreateInstanceFromMigration(inst instance.Instance, conn io
 				return fmt.Errorf("Cannot create volume, already exists on migration target storage")
 			}
 		} else {
-			// Delete the source volume's UUID.
-			// A new one gets set when creating the record in the DB.
-			delete(vol.Config(), "volatile.uuid")
-
 			// Validate config and create database entry for new storage volume if not refreshing.
 			// Strip unsupported config keys (in case the export was made from a different type of storage pool).
+			// A new UUID got already set before.
 			err = VolumeDBCreate(b, inst.Project().Name, inst.Name(), volumeDescription, volType, false, vol.Config(), inst.CreationDate(), time.Time{}, contentType, true, true)
 			if err != nil {
 				return err
@@ -5165,6 +5168,10 @@ func (b *lxdBackend) CreateCustomVolumeFromMigration(projectName string, conn io
 		volumeConfig = dbVol.Config
 	} else {
 		volumeConfig = args.Config
+
+		// Set a new UUID in case the target volume doesn't yet exist.
+		// Some storage drivers might require the UUID to generate the volume name.
+		volumeConfig["volatile.uuid"] = uuid.New().String()
 	}
 
 	// Check if the volume exists on storage.
@@ -5212,12 +5219,9 @@ func (b *lxdBackend) CreateCustomVolumeFromMigration(projectName string, conn io
 	defer revert.Fail()
 
 	if !args.Refresh {
-		// Delete the source volume's UUID.
-		// A new one gets set when creating the record in the DB.
-		delete(vol.Config(), "volatile.uuid")
-
 		// Validate config and create database entry for new storage volume.
 		// Strip unsupported config keys (in case the export was made from a different type of storage pool).
+		// A new UUID got already set before.
 		err = VolumeDBCreate(b, projectName, args.Name, args.Description, vol.Type(), false, vol.Config(), time.Now().UTC(), time.Time{}, vol.ContentType(), true, true)
 		if err != nil {
 			return err