Setting Up NFS Server and Client Configuration

Package Installation

Install the required packages:

dnf install nfs-utils

nfs-utils includes both server and client tools. The separate rpcbind package is no longer needed on modern systems — it’s handled as a dependency and runs as part of the NFS service.

Configure /etc/exports

Edit /etc/exports to define which directories clients can mount and with what permissions. Each line specifies a directory, the clients allowed to access it, and mount options.

Example: allow the 10.0.0.0/24 subnet to mount /home with read/write access:

/home 10.0.0.0/24(rw,sync,no_subtree_check,no_root_squash)

Common options:

• rw — read/write (default is ro)
• sync — flush writes to disk immediately (safer, slower)
• async — buffer writes (faster, riskier on power loss)
• no_subtree_check — disable subtree checking (recommended for modern setups)
• no_root_squash — allow root on client to write as root on server (security risk; avoid unless necessary)
• root_squash — map root to nobody (default, recommended)
• all_squash — map all users to nobody

For more granular control, specify individual hosts:

/data 192.168.1.10(rw,sync) 192.168.1.11(ro,sync)

Or use CIDR notation for subnets:

/var/backups 172.16.0.0/16(rw,sync)

After editing /etc/exports, apply the changes:

exportfs -ra

Use exportfs -v to verify the current export list.

Enable and Start the NFS Service

Enable NFS to start on boot:

systemctl enable nfs-server
systemctl start nfs-server

Check the status:

systemctl status nfs-server

Firewall Configuration

NFS uses dynamic ports by default, which complicates firewall rules. To restrict NFS to fixed ports, edit /etc/nfs.conf:

[nfsd]
port = 2049

[mountd]
port = 20048

[statd]
port = 662

[lockd]
port = 32803

Then restart NFS:

systemctl restart nfs-server

Allow these ports through the firewall using firewalld:

firewall-cmd --permanent --add-port=2049/tcp
firewall-cmd --permanent --add-port=2049/udp
firewall-cmd --permanent --add-port=20048/tcp
firewall-cmd --permanent --add-port=20048/udp
firewall-cmd --permanent --add-port=662/tcp
firewall-cmd --permanent --add-port=662/udp
firewall-cmd --permanent --add-port=32803/tcp
firewall-cmd --permanent --add-port=32803/udp
firewall-cmd --reload

Or with ufw on Debian/Ubuntu systems:

ufw allow 2049/tcp
ufw allow 2049/udp
ufw allow 20048/tcp
ufw allow 20048/udp

Configure NFS Clients

Package Installation

Install the client tools:

dnf install nfs-utils

On Debian/Ubuntu:

apt-get install nfs-common

Mount the NFS Export

Create a mount point and mount the remote directory:

mkdir -p /mnt/nfs
mount -t nfs SERVER_IP:/home /mnt/nfs

Specify NFS version explicitly (recommended for compatibility):

mount -t nfs -o vers=4.2 SERVER_IP:/home /mnt/nfs

Verify the mount:

mount | grep nfs
df -h /mnt/nfs

Persistent Mounts with /etc/fstab

Add a line to /etc/fstab to mount on boot:

SERVER_IP:/home /mnt/nfs nfs vers=4.2,defaults,_netdev 0 0

The _netdev option tells systemd the mount depends on network availability.

Then test:

mount -a

Automount with systemd

For automatic mounting only when accessed, create a systemd .mount file at /etc/systemd/system/mnt-nfs.mount:

[Unit]
Description=NFS mount for /home
After=network-online.target
Wants=network-online.target

[Mount]
What=SERVER_IP:/home
Where=/mnt/nfs
Type=nfs
Options=vers=4.2,defaults

[Install]
WantedBy=multi-user.target

Enable and start it:

systemctl daemon-reload
systemctl enable mnt-nfs.mount
systemctl start mnt-nfs.mount

Debugging and Troubleshooting

Server-side diagnostics

Check NFS service status:

systemctl status nfs-server
systemctl status nfs-mountd

List exported directories:

exportfs -v

Check which ports NFS is listening on:

ss -tlnp | grep -E ':(2049|20048|662|32803)'

Show active NFS connections:

nfsstat -s

Monitor NFS operations in real time:

nfsstat -l

Client-side diagnostics

Check if the NFS server export is accessible:

showmount -e SERVER_IP

List currently mounted NFS shares:

showmount -a

Verify RPC communication:

rpcinfo -p SERVER_IP

Check mounted NFS filesystems and their status:

nfsstat -c
mount | grep nfs

Test NFS performance:

iozone -e -i 0 -i 1 -s 100M -+n -r 4k /mnt/nfs/testfile

Common Issues

Stale NFS file handle errors: Usually caused by the server restarting while clients are connected. Unmount and remount the client:

umount -f /mnt/nfs
mount -t nfs SERVER_IP:/home /mnt/nfs

Slow performance: Check network latency and consider using async mode (with risk) or tuning read/write buffer sizes:

mount -t nfs -o vers=4.2,rsize=65536,wsize=65536 SERVER_IP:/home /mnt/nfs

Permission denied: Verify /etc/exports permissions and that the client IP is in the allowed range. Check file ownership on the server.

Connection timeout: Ensure the server is reachable (ping), firewall rules are correct, and NFS service is running on the server.