init NFS server/client on ubuntu

nfs_client.sh

#!/bin/sh
# https://ubuntu.com/server/docs/service-nfs

# client
# https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/4/html/reference_guide/s2-nfs-client-config-options
sudo mount 172.16.0.7:/home/ubuntu/nfsroot /opt/172-16-0-7/ -o nfsvers=2
cat /proc/mounts | grep nfsroot
cat /opt/172-16-0-7/README.md

# sudo umount /opt/172-16-0-7/

nfs_server.sh

#!/bin/sh
# https://ubuntu.com/server/docs/service-nfs
# server
sudo apt install nfs-kernel-server -y
sudo systemctl start nfs-kernel-server.service
# for nfs2 -> https://unix.stackexchange.com/a/603364/325365

mkdir nfsroot -p
sudo exportfs -o rw,async,no_subtree_check,no_root_squash 172.16.0.5:/home/ubuntu/nfsroot/
echo Hello, world! > nfsroot/README.md

# sudo exportfs -ua