Introduction
NFS is very useful tool to mount volumes and share files. That is also used as a PersistentVolume of Kubernetes, so it is meaningfull that to know how to launch nfs server on your RaspberryPi on recent k3s movement.
Install NFS
If you use raspbian, you just execute a command.
$ sudo apt-get install -y nfs-common nfs-server
Please make directory to be mounted.
$ sudo mkdir /mnt/share
$ sudo chmod -R 777 /mnt/share
Then, add setting to /etc/exports
$ echo '/mnt/share 192.168.123.0/24(rw,async,no_root_squash)' >> /etc/exports
Please check appropriate IP on your cluster.
async means write data to the volume asyncly. no_root_squash means disable the feature of root_squash. root_squash means that it blocks to get root priviledges by remote access users. no_root_squash is not secure, but sometimes it blocks to change existing files. Please consider about what is the best setting for your system.
OK, then start the server.
$ systemctl start rpcbind nfs-server
It is optional, but you can set auto start with this command.
$ systemctl enable rpcbind nfs-server
You can check nfs works or not with this command.
$ exportfs
It will show error if something wrongs.
Mount from another host
Please log in to another host and mount the volume with this command.
sudo mount -t nfs -o resvport,rw 192.168.123.11:/mnt/share /home/yoshwata/mnt
Then, check the nfs works by putting a file from remote host.