cd /tmp
wget https://downloads.tableau.com/esdalt/2018.3.3/tableau-tabcmd-2018-3-3_all.deb
Change the version above to the version of your Tableau Server/Online.
Next we install tabcmd using dpkg and delete the debian package.
sudo dpkg -i /tmp/tableau-tabcmd-2018-3-3_all.deb
rm /tmp/tableau-tabcmd-2018-3-3_all.deb
You will have to exit and reconnect to your host after installation to get tabcmd in your $PATH. Ensure it's there with which tabcmd. Once installed accept the EULA with: tabcmd version --accepteula
For the export to work you will also need the java runtime installed: sudo apt-get install openjdk-8.jre-headless