Enable the SVM for NFS. Refer to ONTAP 9 documentation.

Create at least two LIFs per controller. Follow the steps from the documentation. For reference, here is a screenshot of LIFs used in the lab.

Create or update an NFS export policy to provide access to OpenNebula host IP addresses or subnets. Refer to Export policy creation and Add rule to an export policy.

Create a volume. For large capacity needs (>100TB), check the option to distribute data across the cluster to use FlexGroup. If using FlexGroup, consider enabling pNFS on the SVM for better performance by following Enable pNFS on SVM. When using pNFS, ensure the OpenNebula hosts has data access to all controllers (data LIFs). Ensure Anti-Ransomware protection is enabled on the volume.

Notify the virtualization administrator that the NFS volume is ready and provide NFS export path details.

Ensure at least two interfaces are configured in different VLANs for fault tolerance. Use NIC bonding.

SSH to one of the frontend server and create a configuration file based on desired Datastore type. Sample files are shown below:

$cat nfs-restic.conf
NAME = "Backup-Restic-NFS"
TYPE = "BACKUP_DS"

DS_MAD = "restic"
TM_MAD = "-"

RESTIC_PASSWORD = "<restic_password>"
RESTIC_SFTP_SERVER = "<backup server>"

$cat nfs-rsync.conf
NAME = "Backup-Rsync-NFS"
TYPE = "BACKUP_DS"

DS_MAD = "rsync"
TM_MAD = "-"

RSYNC_USER = "<rsync_user>"
RSYNC_HOST = "<backup server>"

$cat nfs-kernel.conf
NAME = "File-Kernel-NFS"
TYPE = "FILE_DS"
DS_MAD = "fs"
TM_MAD = "local"
SAFE_DIRS = "/var/tmp/files"

$cat nfs-image.conf
NAME = "Image-NFS"
TYPE = "IMAGE_DS"
DS_MAD = "fs"
TM_MAD = "shared"

$cat nfs-system.conf
NAME = "System-NFS"
TYPE = "SYSTEM_DS"
TM_MAD = "shared"

Execute onedatastore create <configuration file>. Note the datastore ID returned after creation.

Gather the uid and gid of oneadmin user using id oneadmin command.

Update /etc/fstab or automount configuration to mount the datastore with desired mount options. Assuming the default datastore location as /var/lib/one/datastores. Can be validated with onedatastore show <datastore_id>. If not check the DATASTORE_LOCATION parameter in /etc/one/oned.conf. Ensure the <datastore_id> folder exists under the datastores location. Sample entries are shown below:

# To use session trunking, use the option trunkdiscovery
//<nfs_server>/<nfs_share> /var/lib/one/datastores/<datastore_id> nfs nconnect=8,max_channels=16,_netdev,noauto,x-systemd.automount,nofail,uid=<oneadmin uid>,gid=<oneadmin gid> 0 0

# To use session trunking, use the option trunkdiscovery
/var/lib/one/datastores/<datastore_id> -fstype=nfs,nconnect=8,max_channels=16,_netdev,noauto,x-systemd.automount,nofail,uid=<oneadmin uid>,gid=<oneadmin gid> <nfs_server>:/<nfs_share>

Mount the datastore using mount -a or systemctl reload autofs command.

Verify the datastore is mounted with mount command and verify the datastore capacity with onedatastore show <datastore_id> command.

Ensure oneadmin user and group own the datastore folder. Adjust permissions using chown -R oneadmin:oneadmin /var/lib/one/datastores/<datastore_id> command.

To verify the nConnect option is set, run ss -an | grep :2049 on any OpenNebula host and check for multiple connections to the NFS server IP. To verify pNFS is enabled, run nfsstat -c and check the layout-related metrics. Based on data traffic, multiple connections to data LIFs should be visible.