I'm trying to setup an automatically mounted volume, and noticed that there is now an /etc/fstab.d/ on my server. I created a new file in the directory with the following contents:

# backupstore: large volume

/dev/mapper/bagend-backupstore  /mnt/backupstore        ext4    auto,relatime,users,sync        0       0

But when I run mount -a the volume is not mounted. Also, when I run mount /mnt/backupstore or /dev/mapper/bagend-backupstore I get told that the system couldn't find the entry in fstab (and to pre-empt: yes, the device and mount-point are correct - I can easily mount this with mount -t ext4 /dev/mapper/bagend-backupstore /mnt/backupstore)

When I delete the file from /etc/fstab.d/ and put the entry into the main /etc/fstab file, I have no problems mounting the volume.

So, can the mount command be made to check for entries in /etc/fstab.d/ and if yes, what do I do to make it happen?