Minimum requirements

Minimum requirements are:

  • 64 bit CPU (x86_64)
  • 1 GB of RAM
  • 10 GB of disk space


We recommend to use at least 2 disks to setup a RAID 1. The RAID software will ensure data integrity in case of a disk failure.

Hardware compatibility

NethServer is compatible with any hardware certified by Red Hat® Enterprise Linux® (RHEL®), listed on

Installation types

NethServer supports two installation modes. In short:

Installing from ISO

  • Download the ISO image
  • Prepare a DVD or USB stick
  • Follow the wizard

Installing from YUM

  • Install CentOS Minimal
  • Configure the network
  • Install from network

Installing from ISO


The ISO installation will erase all existing data on hard drives!

Media creation

Download the ISO file from official site The downloaded ISO file can be used to create a bootable media such as DVD or USB stick.

USB stick

On a Linux machine, open the shell and execute:

dd if=NethServer.iso of=/dev/sdc

Where NethServer.iso is the file name of the downloaded ISO and /dev/sdc is the destination device corresponding to the USB key and not a partition (such as /dev/sdc1).

On a Windows machine, make sure to format the USB drive then unmount it. Use one of the following tools to write the USB stick:


The creation of a bootable DVD is different from writing files into USB stick, and it requires the use of a dedicated function (e.g. write or burn ISO image). Instructions on how to create a bootable DVD from the ISO are easily available on the Internet or in the documentation of your operating system.

Install modes

Start the machine using the freshly backed media. If the machine will not start from the DVD or USB stick, please refer to the documentation of the motherboard BIOS. A typical problem is how boot device priority is configured. First boot device should be the DVD reader or USB stick.

On start a menu will display different types of installation:

NethServer interactive installation

It allows you to select the language, configure RAID support, network, and encrypted file system. It will be described in depth in the next paragraph.

NethServer unattended installation

This installation mode does not require any kind of human intervention: a set of default parameters will be applied to the system.

Standard CentOS installations

Use the standard CentOS installation procedure.


Start the system in rescue (recovery) mode, execute a memory test or start the hardware detection tool.

Boot from local drive

Attempts to boot a system that is already installed on the hard disk.

At the end of the installation process you will be asked to reboot the machine. Be sure to remove the installation media before restarting.

Unattended mode

After installation, the system will be configured as follows:

  • User name: root
  • Default password: Nethesis,1234
  • Network: DHCP enabled on all interfaces
  • Keyboard: en
  • Time zone: Greenwich
  • Language: English
  • Disks: if there are two or more disks, a RAID 1 will be created on first two disks

Install options

You can add extra parameters to unattended installation by pressing TAB and editing the boot loader command line.

To disable raid, just add this option to the command line:


If you need to select installation hard drives, use:


Other available options:

  • lang: system language, default is en_US
  • keyboard: keyboard layout, default is us
  • timezone: default is UTC Greenwich
  • fspassword: enable file system encryption with given password This option can be used even in Interactive Mode

Interactive Mode

The interactive mode allows you to make a few simple choices on the system configuration.

Required choices are:

  • Language
  • Keyboard layout
  • Root password

All other options are set to a reasonable default accordingly to current hardware, but you’re free to edit any install configuration available.

Software RAID

RAID (Redundant Array of Independent Disks) allows you to combine all the disks in order to achieve fault tolerance and an increase in performance.

This screen is displayed when two or more disks were detected at start.

Most used levels are:

  • RAID 1: it creates an exact copy (mirror) of all the data on two or more disks. Minimum number of disks: 2
  • RAID 5: it uses a subdivision of the data at the block level, distributing the parity data evenly across all disks. Minimum number of disks: 3

System administrator password

You’re strongly advised too choose a secure password for the root user.

A good password is:

  • at least 8 characters long
  • contain uppercase and lowercase letters
  • contain symbols and numbers

Default password is Nethesis,1234.

Encrypted file system

When enabling this option, all data written to the disk will be encrypted using symmetric encryption. In case of theft, an attacker will not be able to read the data without the encryption key.


You will need to enter the encryption password at every system boot.

Network configuration

As default, all network interfaces are configure with DHCP. Please, read the following notes before customizing network configuration.

Host and Domain Name (FQDN)

Type the host name and domain in which the server will operate (e.g. Domain name should only contain letters, numbers and the dash.

IP Address

Type a private IP address (from RFC 1918) to be assigned to the server; if you want to install it in an existing network, you must provide a unused IP address valid for that network (in general you can use the first or last host inside the network range, e.g. or


Type the subnet mask of the network. You can safely leave the default value.


Type the IP address of the gateway on which you are installing the server.

End of installation procedure

After parameters input, the procedure will start the installation.

At the end of the installation procedure, access the server-manager to install additional software.

Install on CentOS

It is possible to install NethServer on a fresh CentOS installation using the yum command to download software packages. This is the recommended installation method if you have

  • a virtual private server (VPS), or
  • an USB stick.

For example, if you wish to install NethServer 7, just start with a CentOS 7 on your system (many VPS providers offer CentOS pre-installed virtual machines), and then execute below commands to transform CentOS into NethServer.

Enable specific YUM repositories with this command:

yum localinstall -y

To install the base system, run:


Alternatively, to install base system and additional modules, pass the name of the module as a parameter to the install script. Example:

nethserver-install nethserver-mail nethserver-owncloud

At the end of the installation procedure, access the server-manager to install additional software.