Request a login (username and password) for the Rentouch-Docker-Hub from Rentouch if you do not already have one.
docker login harbor3.piplanning.io
If your server does not have a connection to the internet:
Install the updated offline installable images
Request a download link from rentouch for the updated .tar archived docker images.
Move the .tar archive to the server on which you are installing pi-server.
Input the command:(this may take a few minutes..)
docker load -i pi-server-images_2.7.0.tar
Give your admin account an email address
Before updating: Make sure that your admin account has a valid email (login to the cockpit, settings → set a email address). You will receive a mail to set a new PW at first start after the update. You will need to contact Rentouch if you overlooked that and are locked out.