Build an Ubuntu NAS

Basic Linux, network knowledge is required.
Remember that we are just providing a basic guide for building a NAS, so we can't answer about the advanced usage of each NAS services.
This guide is for XU4/HC1/HC2. You can apply it to C1/C1+/C2 but they haven't USB 3.0 port for the HDDs.
Operation confirmed with testing in our Ubuntu Minimal 16.04.3 LTS on updated 4.9.58-71 kernel.
- Works well on updated 4.14.12-98 kernel and you can download integrated image: Ubuntu Minimal 16.04.3 LTS with 4.14 Kernel
- As always, installing latest kernel is highly recommended.

If there is no special reason to use FTP (Especially domain), we recommend to use SFTP (FTP protocol provided by SSH service) for security matters. For this reason, we don't deal with enabling FTP service.
References (ODROID Forum)
- https://forum.odroid.com/viewtopic.php?f=52&t=23925
- https://forum.odroid.com/viewtopic.php?f=52&t=25424

If you want a high performance NAS and don't need a big storage, try it with a SSD and make it a root partition.
- Refer to this document

This guide will show you how to build a NAS with a clean Ubuntu Minimal image.
If you don't want to install Open Media Vault, this guide would help you. If you build a NAS on Ubuntu, you can install latest packages including PHP, Nginx from apt package manager so that you can easily get the benefits of the latest version. But it requires you to know the basic knowledge of Linux and network.

This guide includes the chapters below:

Basic Settings
Mount HDDs
NGINX, PHP, MariaDB
NAS Services
- Samba
- Plex Media Server
- Serviio
- Transmission
- Seafile
- Sabre/DAV
- Wordpress
- NextCloud
- OpenVPN
Port-forward
Apply DDNS / SSL
- DuckDNS
- Let's Encrypt
Options
- Webmin
- Optimize performance (Click to visit)
  - Emulating HMP
    - Fastest transfers over sshfs/scp/sftp
  - Disk longevity
  - Flash disk (Recommended)
  - Governor
  - Network - MTU (Recommended)
  - Network - interrupts (No more needed. Applied by default)
  - Tune systemd timeouts

Web server components (LEMP stack in our guide) is required to provide PHP or database related services.

Before proceed, make sure that you've burned our latest Ubuntu Minimal image on a MicroSD card or eMMC and inserted properly, and you've connected proper power, network cable, and a HDD in advance.
Then, let's get started.