Yes, I did just crash that critical app. And you should thank me for having done so
- Reference: 1710750548
- News link: https://www.theregister.co.uk/2024/03/18/who_me/
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This week's traveller is someone we'll Regomize as "Harper" who many years ago was developing a Unix-based messaging systems for a large IT provider.
How many years ago? Well, Harper didn't specify, but did mention that the system worked on dumb terminals with green text on a black background. So, not particularly recent.
[1]
At any rate, the system provided all the mod-cons like To: and Cc: and Bcc: fields, as well as allowing users to save email addresses as nicknames to avoid having to type out the whole thing (luxury!). It even enabled creation of mailing lists, all members of which could be mailed using just a short nickname. Beyond that, it was pretty basic, but functional.
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One fine day, Harper received a message from a co-worker we'll call "Greg". The message read, simply, "Hi Harper". Being a congenial team-player sort of guy, Harper replied: "Hi Greg" and office harmony was maintained.
Then Harper got two more messages from Greg in quick succession, both containing only "Hi Harper". This seemed to Harper (and no doubt to you) a bit odd, so a short investigation ensued.
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It transpired that what Greg had done, for whatever reason, was to put Harper's address in all of the To: Cc: and Bcc: fields – thus sending three identical copies of the same decidedly non-urgent communication.
It appeared that the system had no kind of validation in it to avoid sending duplicate emails. To test the theory, Harper and his colleagues in IT tried sending each other messages with their addresses in every field as many times as they would fit (there was a character limit thankfully). This resulted in each of them receiving masses of duplicate test messages and proving a) that there was no validation; and b) that validation was needed.
Harper made a note to fix that at some point in the future.
[5]Intern with superuser access 'promoted' himself to CEO
[6]Health system network turned out to be a house of cards – Cisco cards, that is
[7]If we plug this in without telling anyone, nobody will know we caused the outage
[8]Self-taught-techie slept on the datacenter floor, survived communism, ended a marriage
But first, there was retribution to be had. One must have priorities.
So Harper decided to send Greg some duplicate messages to see how well he enjoyed it. First, he gave Greg a nickname with only one letter in it. Then he created a mailing list with that nickname in it as many times as it would fit. Then he gave that mailing list a single-letter nickname as well. Then he added that single-letter nickname to the To: and Cc: and Bcc: fields of a message, repeatedly, right up to the character limit.
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Then he wrote the message body – "Hi Greg" – and hit send.
You can imagine the chaos that ensued at Greg's end, as he started to receive literally thousands of copies of the same banal greeting in rapid succession.
And while Greg was drowning in emails, Harper and co were wiping away tears of laughter and congratulating themselves on their jolly jape.
Until the phone call came. Someone in the server support team was wondering why the mail server had just "fallen flat on its arse" while people were trying to get work done.
"Quality assurance," replied the silver-tongued Harper. "We're load-testing the mail system, checking if validation has been put in place, that sort of thing. Turns out it hasn't, and it's lucky we caught it now before this went into production."
Thankfully, they bought it – no punishment was meted out for the nefarious prank. In fact, in the years since, Harper told us he always encourages the QA team "to be as dastardly as possible" in testing systems!
What's the best excuse you've ever come up with in the heat of the moment to justify a tech SNAFU? Click here to tell us about it in [10]an email to Who, Me? and we'll probably immortalize your work on some future Monday morn. ®
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[5] https://www.theregister.com/2024/03/11/who_me/
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terminal mail clients are a bit of a Mutt though
Comparing old mail clients to modern mail clients, the Outlook is pretty bleak
I'd better get my coat and head out Eudora
easily fixed with a telnet session to port 25
telnet mailserver1.my.org 25
Did that during Y2K testing, because plaintext is easily scriptable via send/expect.
Re: telnet mailserver1.my.org 25
And in those days (or maybe before the actual moment of Y2K) it was also easy to put God@heaven.org or whatever in the From: field.
as long as you don't catch Elm disease
Reminds me of when I was a nipper working on a helldesk which didn't have a dedicated email address (this was back in the 90s). There was just me and one other guy working on it at the time and users would email us directly for help.
I thought it would be a jolly jape to set up a forward so that every email that came to me got forwarded to him for him to deal with. Once he realised what I'd done, he thought it would be even jollier if he reciprocated and sent them right back to me. It only took a few minutes for the mail server to fall over after we created our loop. In our defence we realised straight away that it was our fault, removed the forwards and once the dust had settled we owned up. Our long suffering boss took it in her stride and just told us not to do it again. Lesson learned.
Sounds like one of my former bosses. He gave me admin access to our production system (because I needed it), along with a few pointers:
- try not to be stupid
- if in doubt, check with somebody more experienced
- trust your own experience - we hired you because you do know stuff, no need to get on my bloody nerves for everything
- if you mess up, own up
- we have backups that we can actually recover from (thankfully we never needed to).
- I will cover my team's actions
And that's exactly what I tell my young colleagues.
This reminds me of wondering aloud what would happen on my father's old telephone switchboard if somebody set multiple phones to redirect in a loop and called one of them from another phone.
Boringly the answer was that if a phone diverted to a phone that the call had already diverted from then it rang instead of diverting.
I had similar years ago (back when external email was nearly all SMTP) with Out of Office emails. Neither the original sender nor the recipient had checked the "Only send once" box.
As we were using an ISDN link from a black-box email concentrator to the provider we only had limited access to administer the system and the link was very quickly swamped. I did manage to track it down, shut down the user's PC and then clear the message queues.
Proper testing
"to be as dastardly as possible in testing systems!"
That's the way it ought to be done. Test the error cases, not just the one that is supposed to work.
This makes you Pine for the email systems of old...