How to setup NFS on Synology NAS for Proxmox Backup Server to use as Datastore

Last Updated on August 5, 2022 by Thiago Crepaldi

In this post we are going to configure a NFS share on our Synology NAS so that Proxmox Backup Server can use it as storage (aka Datastore) for all VMs and container backups.

The first step is to configure NFS share on your Synology, then we need to mount the NFS share on the server running the PBS and lastly we configure a Datastore on the pBS pointing to the folder where the NFS was mounted.

Enabling NFS on the Synology NAS

After login in to your Synology, go to Control Panel >> File Services and scroll down to NFS. By default, NFS is disabled. To enable it, check both “Enable NFS”, “Enable NFSv4 support” and click on Apply.

Create NFS share

Now that you have enabled NFS on your DSM, let’s create a share with it. go to Control Panel >> Shared Folder and click on Create. A wizard will appear:

Set up basic information
- Name: Proxmox Backup Server
- Description: NFS storage for PBS datastore
- Location: pick the appropriate volume, preferably one that is fault tolerant for at least one disk
- Hide this shared folder in “My network Places”: checked
- Hide sub-folders and files from users without permission: checked
- Enable recycle bin: unchecked

Click on Next

Encryption
- Encrypt this shared folder: unchecked

Click on Next

Configure advanced settings
- Enable data checksum for advanced data integrity: unchecked
- Enable shared folder quota: unchecked

Click Next to show a confirmation screen. If everything looks ok, click Apply to create the share.

Once your shared folder has been created, you will be redirected to the Permissions tab, where you need to change all users except your admin account to have No Access.

At this point, you have a shared folder, but it doesn’t have NFS configured. Lets change that by going to NFS Permissions tab and clicking on Create.

Create a NFS rule
- Hostname or IP: Add the IP/hostname of your PBS
- Privilege: Read/Write
- Squash: No mapping
- Security: sys
- Enable asynchronous: checked
- Allow connections from non-privileged ports: unchecked
- Allow users to access mounted subfolders: unchecked

Click Ok to create the NFS rule and take note of the Mount path at the bottom of the page. This is the path you will need to use on the PBS NFS client later.

Mounting NFS share from Proxmox Backup Server

Login to your PBS and go to Administration >> Shell. At the terminal, make sure you have NFS client installed – it should already be installed by default

# apt update
# apt install -y nfs-common

Now we need to create a folder which will be host the NFS mount point and manually mount the Synology share as a test. This is where you are going to use the mount path you took note when configuring NFS rule at your Synology

# mkdir -p /opt/NFSfromSynology
# chown backup:backup /opt/NFSfromSynology
# chmod 775 /opt/NFSfromSynology
# mount synology_hostname:/volume1/ProxmoxBackupServer /opt/NFSfromSynology/
# touch /opt/NFSfromSynology/test_file

After this, you should see a test_file inside ProxmoxBackupServer share on your Synology. Use File Station app on your Synology to verify.

We will also add an entry at /etc/fstab to mount this share point automatically during boot.

# echo "synology_hostname:/volume1/ProxmoxBackupServer /opt/NFSfromSynology/ nfs defaults 0 0" >> /etc/fstab

As a test, we will manually unmount the NFS share and ask the OS to mount it. In between unmounting and mounting again, we try to list files in the mount point. Only after mounting it should show test_file created before.

# umount /opt/NFSfromSynology/
# ls /opt/NFSfromSynology/
# mount -a
# ls /opt/NFSfromSynology/

Adding a Datastore on your Proxmox Backup Server

Now that the NFS share from Synology is mounted on your PBS server, we can use it as a Datastore. On your PBS web UI, click on Datastore >> Add Datastore button

Add Datastore
- Name: NFSfromSynology
- Backing path: /opt/NFSfromSynology
- GC schedule: daily
- Prune schedule: daily
- Comment: NFS share from Synology to store PBS backups

Click Add to complete. After around 30s, you will see a timeout error (aka Connection error – Timeout.). This is a known issue on PBS and it is safe to ignore. Close the Datastore creating window and wait a little longer until you see a “NFSfromSynology” entry under Datastore on the left menu.

With this, we now have a datastore, but it is not quiet usable just yet. We need to give access/permissions to users to use the datastore. In this example we are going to create a new user, so go to Configuration >> Access Control >> User management and click at Add

Add user
- User name: pbs_client
- Password: be creative here
- Confirm password: confirm you are creative
- Expire: never
- Enabled: checked
- First name: PBS
- Last name: Client
- E-mail: your email
- Comment: PBS user that shall be used by PVE to access datastores

Click Add and verify a new user is listed. Note its realm is “pbs“, so the new user created is pbs_client@pbs!

Let’s give pbs_client@pbs access to NFSfromSynology. Through the left menu, go to Datastore >> NFSfromSynology >> Permissions. Click on Add >> User permission and pick pbs_client@pbs from the list, select DatastoreBackup as its Role and finish off by clicking Add. Now the datastore is usable, at least for pbs_client@pbs!

Because we use (for now) self-signed certificates, we need to get the PBS fingerprint so that PVE can trust on the PBS. Go to Administration >> Shell and run the following command and take note the output. It should be 32 hex octets, like ab:cd:ef:01:12:…:ff

# proxmox-backup-manager cert info | grep Fingerprint

Configuring Proxmox Virtual Environment to use the PBS datastore

On your Proxmox Virtual Environment, go to Storage View >> Datacenter >> Storage and click on Add followed by Proxmox Backup Server

Add Proxmox Backup Server
- General
  - ID: PBS_YOUR_SERVER_HOSTNAME (or any friendly name)
  - Server: Your server IP or hostname
  - Username: pbs_client@pbs
  - Password: ********* (tu dun ts)
  - Nodes: All
  - Enabled: True
  - Content: backup
  - Datastore: NFSfromSynology
  - Fingerprint: Copy & Paste from previous steps
- Backup retention:
  - Keep all backups: checked
    - you can tweak this section to your need
- Encryption
  - Do no encrypt backups

Click Add to complete and verify the new entry is displayed in the Storage page.

Backing up a Proxmox Container

To test our new PBS storage, let’s backup a Proxmox container. Go to Folder view >> Datacenter >> LXC Container and select one of your containers. Next, click on Backup followed by Backup now button

Backup CT <xxx>
- Storage: PBS_YOUR_SERVER_HOSTNAME
- Mode: Snapshot

Click Backup to start. A dialog with logs will be displayed. If everything went well, you should see several logs, but the last two should be something like

INFO: Backup job finished successfully
TASK OK

Backing up a Proxmox Virtual Machine

You can do similar test for a Virtual Machine. Go to Folder view >> Datacenter >> Virtual Machine and select one of your VMs. Next, click on Backup followed by Backup now button

Backup VM <xxx>
- Storage: PBS_YOUR_SERVER_HOSTNAME
- Mode: Snapshot