I'm the sysadmin for a medium sized business, we run our own mail server on premises (linux). Of course, I have sudo privileges on that box, and the email server stores emails in mbox format so in principle I am able to access everybody's mailbox and read emails at will.
I strictly follow the System Administrators' Code of Ethics and I never abused my powers (except when specifically ordered by management to make a copy of someone's inbox, before firing the poor lad).
Now, I'm the one getting laid off, and my manager asked me to lock myself out to prevent to be able to read (presumably their) emails; please note that this is still a "friendly" separation and that I'm going to be employed for few months still (to hand over to a new sysadmin, to be hired). I replied that I can't do my job (administering the server) without root access, and she has just to trust me on this.
Is there a way I can lock myself out while retaining full access?