Install Mono

Add the apt key

sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF

Add the source list

echo "deb https://download.mono-project.com/repo/ubuntu stable-focal main" | sudo tee /etc/apt/sources.list.d/mono-official-stable.list

Update the apt list

sudo apt update

Install Mono and it’s needed extras

sudo apt install mono-devel gtk-sharp2 libappindicator0.1-cil libmono-2.0-1

Installing Duplicati

Install the prerequisites

sudo apt install apt-transport-https nano git-core software-properties-common dirmngr -y

Download the latest version. Go to https://www.duplicati.com/download, find the Ubuntu link and copy the link address. At time of writing the link is https://updates.duplicati.com/beta/duplicati_2.0.6.1-1_all.deb. Use wget to download this.

wget https://updates.duplicati.com/beta/duplicati_2.0.6.1-1_all.deb

Install the downloaded file, change the file name, to match the file name you downloaded above.

sudo apt install ./duplicati_2.0.6.1-1_all.deb -y

Create the systemd service

sudo nano /etc/systemd/system/duplicati.service

Paste the following and save

[Unit]
Description=Duplicati web-server
After=network.target

[Service]
Nice=19
IOSchedulingClass=idle
EnvironmentFile=-/etc/default/duplicati
ExecStart=/usr/bin/duplicati-server $DAEMON_OPTS
Restart=always

[Install]
WantedBy=multi-user.target

Edit the config file for the settings for Duplicati

sudo nano /etc/default/duplicati

Edit DAEMON_OPTS="" to be the below. You can change the webservice-port if it’s going to clash with anything else, and the webservice-interface if you want to bind one address.

DAEMON_OPTS="--webservice-interface=any --webservice-port=8200 --portable-mode"

Enable and start the Daemon

sudo systemctl enable duplicati.service
sudo systemctl daemon-reload
sudo systemctl start duplicati.service 

To check the status run

sudo systemctl status duplicati.service

First run

Browse to http://serverip:8200 and you should get the first run wizard.