What should we do if APT gives the warning "Missing signed-by=" or indicates the removal of the "trusted.gpg.d" key while updating our repositories?
One of the basic, regularly recurring tasks of maintaining our Debian or Ubuntu-based servers and systems is updating the package repositories and installed software. I was just doing the usual update cycle on my server these days, which has been a bit behind lately, so I expected that several packages would be updated. However, the update process stopped with interesting messages that drew attention to an important change related to the management of the signing keys of the package repositories. In this article, we will look at how to deal with these problems.