Install NFS on Ubuntu:
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This is a type of NAS for UNIX based/like systems, work on windows 10 as well.
This will export a NAS folder and apache web folder as examples
For the NAS folder you will need to mount the drive on the right folder and add it to the fstab correctly. As well create the folder with mkdir.
For the web server directory you will need to have apache2 and php already installed for the folder to be there.

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First make the folders you need and make then readable/writeable by anyone such as:
sudo chmod -R 777 /var/www/html
sudo chmod -R 777 /opt/RD/NAS
sudo chmod -R 777 /opt/RD/SNAS
sudo chmod -R 777 /opt/RD/UNAS
sudo chmod -R 777 /opt/RD/MNAS

You will need to do this in the future since the files could get locked to one machine and os.

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Then install nfs-kernel-server by:
sudo apt install nfs-kernel-server

And start it by:
sudo systemctl start nfs-kernel-server.service

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Then edit the export list by:
sudo nano /etc/exports
and add these lines:


/opt/RD/NAS 192.168.10.0/24(rw,async,no_subtree_check) 10.8.0.0/24(rw,async,no_subtree_check)
/var/www/html 192.168.10.0/24(rw,async,no_subtree_check) 10.8.0.0/24(rw,async,no_subtree_check)
/opt/RD/SNAS 192.168.10.0/24(rw,async,no_subtree_check) 10.8.0.0/24(rw,async,no_subtree_check)
/opt/RD/UNAS 192.168.10.0/24(rw,async,no_subtree_check) 10.8.0.0/24(rw,async,no_subtree_check)
/opt/RD/MNAS 192.168.10.0/24(rw,async,no_subtree_check) 10.8.0.0/24(rw,async,no_subtree_check)
/var/log 192.168.10.0/24(rw,async,no_subtree_check) 10.8.0.0/24(rw,async,no_subtree_check)

#NAS = NAS
#SNAS - Secondaru NAS or Super NAS
#UNAS = Ultra NAS
#WNAS = Web NAS
#MNAS = Mini NAS
#log-nas = Read only nas to view log files easier for server.


*Remove old entries by:
sudo exportfs -r

Then save changes then export the list to open these nfs folders by:
sudo exportfs -a


Then you can view it exported successfully by:
sudo exportfs

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You may need to restart the NFS server or reboot the machine entirely and then you can now mount your NFS shares.
Restart NFS with command: sudo systemctl restart nfs-kernel-server

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Source: https://ubuntu.com/server/docs/service-nfs
Date: March 27th, 2021

Update: February 24th 2022:

*You may also need to install "sudo apt install nfs-common" on your client to mount nfs share.

Source: https://askubuntu.com/questions/525243/why-do-i-get-wrong-fs-type-bad-option-bad-superblock-error/525246

Updates: July 31st 2023 *Fixed some things:
https://www.digitalocean.com/community/tutorials/how-to-set-up-an-nfs-mount-on-ubuntu-22-04

Update (April 19th 2024): Added NFS share for server logs.