I have taken over the system administration on an ubuntu system from someone else. I had an normal user account on this system before, that I am still using. The previous admin made me sudoer, so in principle I have almost all priviledges I need to administrate that computer. However, as Ubuntu by default sets the first user created during installation as the super user (i.e. the previous sysadmin), I am facing the problem that for specific tasks I am still asked for the previous admin's password, particularly when being logged in on the GUI with my account and accessings things like GUI-based printer or user administration, update management etc..
One solution I thought about already was to just use my sudoer priviliges to change the password of the previous sysadmin (who does not need his account anymore). However, I would find it much more elegant just to make my account the main system administrator. Is there a way to do this post installation?
Thanks in advance for help on this!