He knows what you should be doing and how you should be doing it -- and he's not afraid to take matters into his own hands if you don't agree. A well-intentioned but overzealous admin can often do as much harm as a malicious one.
There are lots of rogue activities that don't involve disgruntled employees, says Josh Stephens, head geek for SolarWinds, maker of network management software.
"A rogue admin could simply be someone who chooses to do things his way instead of the company's way," he says. "Say your organization has standardized on Windows, but your rogue guy loves Linux. Three months down the road, you may discover that a third of your servers are now using Linux."
Sometimes, though, when the crusader takes over, destruction results. Back in the mid-'90s, Jon Heirmerl worked for a software developer on a government contract.
"We had one network administrator -- I'll call him Jim -- who would walk the halls looking for people who left their desks with their terminals still logged on," says Heirmerl, who's now director of strategic security for Solutionary, a managed security solution provider. "If Jim found a terminal still logged on, he would go into that person's system and delete all their files to 'teach them a lesson.'"
Then one day a senior developer caught Jim in the act as he was deleting files. The developer, who had no recent backups and lost months' worth of work an instant after Jim hit the Delete key, went postal.
"He punched Jim in the face," says Heirmerl. "Jim didn't delete any more files after that."
Perhaps the best-known crusader is Terry Childs, the former network administrator for the City of San Francisco who refused to surrender passwords to key city systems because he felt his supervisors were incompetent. Childs was convicted of violating California's computer crime laws in April 2010 and is now serving a four-year term in state prison.
"It's fair to say [people like Terry Childs] think they're doing the right thing," says Santorelli. "Hitler also thought he was doing the right thing. Just because you feel justified isn't a defense for criminal acts. Most people would argue there are sufficient safeguards that allow you to be a whistleblower without restorting to destruction, whether it's the media, government, or some regulatory agency."