I know a similar story of a sysadmin who did the same, but went into the lab and sat down next to the student. And then put his handgun on the table.
Power tripping assholes.
Source: I was a sysadmin.
So I got my hands on the root passwords for all the office servers. In particular, there was a SPARC 2 that had both "intranet" and external functions. I pored over manual pages for awhile and I discovered this amazing concept called "C2 security". It described security manuals which I could not obtain or read and it promised to tighten up the system according to federal regs. How could I resist?
So I found the SunOS command called something like "C2conv"; I su'd and I ran it. Much to my horror the /etc/passwd file got sort of ripped apart into /etc/shadow (which was a very unfamiliar concept in 1994) and the system became sort of non-functional. Also to my exploding-head level horror, there was literally no such thing as "C2unconv" because it was a one-way conversion. So I had to sort of manually pick through the changes and fix it up before my boss really noticed. And I did get it working again. But I was terrified by that.
Obviously, for our operational network, working with telecoms and large-scale customers who leased T-1s and so forth, we had rigid policies on scheduled maintenance, customer notification, outage windows and so forth. I really had no clue if any of that applied to my sysadmin job and the servers under my care. It was a wild ride during the "dot-com boom", I tell ya.
I could Google but it's more fun to vaguely remember.
Also, this was the late 90s and while you could get linux running, all the servers were Unix, and the profs made it very clear any issues between differences between Linux and Solaris were ours to deal with... so we were essentially forced to login to their servers. We are truly our own worst enemy sometimes.