Exports (Shares)

Tip

A unified export directory is automatically created in NFSv4.2.

Info

See export options for export option details.

ZFS NFS Exports

Tip

Recommend keeping all NFS operations in NFS to minimize confusion.

ZFS will export datasets directly to nfs-kernel-server on the host enabling portable NFS configurations with the respective datasets. This has no performance benefits in linux as ZFS just auto exports basic configurations to /etc/exportfs.d/zfs.exports.

Each ZFS dataset has it's own unique FSID, so it does not need to be specified unless there are sub-directories inside that dataset that are shared as well.

Enable Extended Attributes

Reduces I/O requests and latency via enabling larger inode allocations for attributes. Enable large dynamic inode sizes (>512B) for all exported datasets.

# large_dnode is automatically enabled when dnodesize != legacy.
zfs set xattr=sa dnodesize=auto {POOL}/{DATASET}

Create NFS exports on ZFS filesystem.

Specify rw=, ro= before other options. Use mountpoint to automatically export based on the dataset mount point.

Tip

Commas (,) should be used to separate multiple rw=, ro= host definitions. These will be auto-exported as separate lines in /etc/exports.d/zfs.exports.

# ZFS mount point required.
zfs set mountpoint=/d/backup {POOL}/backup

# zfs set sharenfs="{HOST},{HOST_N},{OPTION},{OPTION_N}" {POOL}/{DATASET}
zfs set sharenfs="rw=10.10.10.0/24,sec=sys,fsc,mountpoint,no_all_squash,crossmnt,nohide,no_subtree_check,anonuid=65534,anongid=65534" {POOL}/backup
zfs share {POOL}/backup

Exports are restricted based on the host restrictions; ensure networks are wire isolated or use full encryption (sec=krbp).
Exported directory is the ZFS mountpoint not the ZFS dataset name.

Refresh ZFS NFS exports if the haven't automatically been refreshed.

systemctl restart zfs-share.service  # Automatically runs 'exportfs -a'.
exportfs  # Show currently exported filesystems.

Exports via /etc/exports

Traditional NFS exports. Prefer ZFS Exports.

/etc/exports

0644 root:root

# {EXPORT} {HOST}({OPTIONS}) ... {HOST_N}({OPTIONS})
/exported 10.10.10.0/24(sec=sys,fsc,no_all_squash,crossmnt,nohide,no_subtree_check,anonuid=65534,anongid=65534)

Refresh exports.

exportfs -a  # Refresh NFS kernel server exports (done automatically).
exportfs  # Show currently exported filesystems.