Junior techie rushed off for fun weekend after making a terminal mistake that crashed a client

Using one green screen to manage multiple machines needs more than a Friday afternoon brain

Who, Me? Shifting focus from weekend fun to the reality of a return to work can be hard, so The Register tries to ease the transition with a fresh instalment of "Who, Me?", our reader-contributed column that tells your stories of making mistakes and making it out alive afterwards.

This week, meet a reader we'll Regomize as "Bill" who told us about his very first job, fresh out of university, working to support a client's fleet of IBM AS/400 midrange computers.

Bill's duties saw him work with both on-prem AS/400s and customers' machines that he accessed remotely, over modems that sped along at perhaps 2400bps! He used the same tool to access either type of machine: a 5250 green screen dumb terminal.

Working on AS/400s was fun because, as Bill reminded us, "commands were invariably constructed from mnemonics of the words."

"WRKCFGSTS, for example, meant ‘work with configuration status functions'. WRKACTJOB meant ‘work with active jobs'."

Another command, PWRDWNSYS powered down a system, with optional parameters RESTART(*YES) or RESTART (*NO) offering the chance to specify a reboot or complete shutdown.

Bill had spent a very busy and tiring week using an on-prem AS/400 while also being logged onto a customer machine. As 5pm Friday approached, he tidied his desk so he could make a swift exit for a planned weekend away.

As soon as was decent, he entered the PWRDWNSYS RESTART(*NO) command, switched off his terminal, and left.

"This happened in a time before mobile phones, and I had a fantastic weekend," Bill told Who, Me?

His Monday started in a far less pleasant fashion.

"As I walked in, I could sense everyone was looking at me."

He was soon told why: Bill hadn't shut down the local AS/400. In his rush to leave for the weekend, he'd shut down the client's machine.

Which was their production box, in an uncrewed datacenter.

In case you're not aware, clients of IT service providers don't pay to have their servers broken and applications go down.

Bill can't recall what the app he shut down did, and remains unaware of the extent of any chaos he unleashed.

"I kept my job, and we kept the customer," Bill told Who, Me? "But we did have to give them an awful lot of professional services free of charge, and we did have to buy them beer."

Have you mistakenly shut down something you were supposed to keep running? To share your story, click here to send us an email. Bill's story came in last week, along with a couple of others, but the mailbag remains a little bare and we could use some more contributions. ®