Introduction

Compared to my Raspberry PI description, a Linux Ubuntu server is installed in a virtual machine here. This installation will be used for a test system only. For a productive environment, there is certainly a lot more that needs to be done in relation to cyber security.

VMware

For the virtual machine, VMware Fusion is used with the Ubuntu Server 18.04.3 LTS. When installing in VMware, the "easy installation" was deselected. And for the BIOS, the "old BIOS" option was used. For the other settings of the VMware the following values was used:

• 2 CPU cores
• 4096 MB RAM
• 3D acceleration has been switched off
• Hard drives size 64GB, divided into multiple files

Then the default settings can be used during installation. Only the keyboard was identified manually and the "Install OpenSSH server" option was used. The installation can take a few minutes.

Updating & upgrading

After logging in for the first time, an update and upgrade should now be done:

• sudo apt update
• sudo apt upgrade

This can take a while. But at the end the software is up to date.

Static IP address

The default settings for the IP address in VMware are DHCP with NAT translation. But here I want to use a static IP address in bridged mode. Furthermore I do not want to use the new netplan, I want to use the ifupdown functionality. Therefore use the following command first:

• sudo apt install ifupdown
• sudo apt purge netplan.io

In VMware, the mode can now be switched from NAT to Bridged. In general some changes must be done in /etc/network/interfaces. Here I will use nano for the editor. Therefor the following command is used:

• sudo nano /etc/network/interfaces

ens33 is the ethernet interface in my VMware. The next lines are just an example. They need to be changed according to your infrastructure:

auto lo ens33
iface lo inet loopback
iface ens33 inet static
    address 192.168.0.24
    netmask 255.255.255.0
    network 192.168.0.0
    gateway 192.168.0.254

The DNS server must be set in /etc/systemd/resolved.conf:

• sudo nano /etc/systemd/resolved.conf

Set the DNS entry according to your infrastructure:

DNS=192.168.0.254

After these changes make a reboot with:

• sudo reboot

After the reboot the new values should be used by the system.

Disabling IPv6

For disabling IPv6 the content of /etc/sysctl.conf must be changed. Therefore type:

• sudo nano /etc/sysctl.conf

And add the following lines [Source]:

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1

To apply the changes, the following command has to be executed:

• sudo sysctl -p

Now IPv6 is disabled.

Timezone

To set the timezone for Europe/Berlin use the following command:

• sudo timedatectl set-timezone Europe/Berlin

The settings can be checked with the command timedatectl.

Housekeeping

From time to time you should check for updates and upgrade your system. In short, use the following commands:

• sudo apt update
• sudo apt upgrade
• sudo apt clean

Docker / Docker Compose

For the installation of docker the following commands are needed:

• cd
• curl -fsSL get.docker.com -o get-docker.sh
• sh get-docker.sh
• sudo usermod -aG docker <username>
• sudo reboot

To verify that Docker is installed and running type:

• docker version
• docker info

You should see now some information about versions and other things. Another test is the Docker hello-world:

• docker run hello-world

If everything is installed correctly, the message "Hello from Docker!" should appear. If Docker has now been installed correctly, the "Docker Compose" tool can be installed. The following commands are used for this purpose:

• sudo curl -L "https://github.com/docker/compose/releases/download/1.25.0/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
• sudo chmod +x /usr/local/bin/docker-compose

To verify that Docker Compose is installed type:

• docker-compose version

If you see some version information now, Docker and Docker Compose have been installed correctly.