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What is the Worst Tech Mistake You Ever Made?

Cliff posted more than 10 years ago | from the let's-learn-from-them dept.

Technology 503

CraigEagle asks: "Mistakes are made every day. The more technical knowledge you have the bigger your mistakes can be. What is the biggest technology related mistake you have ever made?"

"In the interest of full disclosure, this is mine:

I was working at a Fortune 50 bank as a consultant. I was due to go on vacation for a week and the company did not have webmail. I decided that I would try forwarding emails to my corporate account. (I know this was a bad idea, and probably against several corporate policies.) I set it up so that any email that came in would forward to my consulting company's account. My mistake was I also left Delivery Receipt on. This was not Microsoft, it was Lotus Notes. The system began forwarding the incoming mail to my account. But then it would get a Delivery Receipt, which in turn would be forwarded to my account, which would generate another delivery receipt, ad infinitum. When I got back from vacation they claimed I had brought down the email system for 4 hours. This incident caused the bank to stop allowing consultants to set up email rules. What's your story?"

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503 comments

A long time ago (1)

MacBrave (247640) | more than 10 years ago | (#7915841)

During my IBM mainframe, COBOL, VSAM, CICS days at a large midwestern bank, I crashed the entire CICS online system for about a day because of a screw up when allocating memory within the CICS region.

About 300 branches were not happy.....

One time... (5, Funny)

PeekabooCaribou (544905) | more than 10 years ago | (#7915856)

I launched SkyNet, right before my daughter and future husband rushed in to warn me. Boy was my face red!

Re:One time... (0)

Anonymous Coward | more than 10 years ago | (#7915906)

Dammit! I just blew all my moderator points. I owe you for Faygo Redpop coming out my nose. :)

Re:One time... (0)

Anonymous Coward | more than 10 years ago | (#7916196)

What the hell is SkyNet?

File errors (2, Interesting)

dfreed (40276) | more than 10 years ago | (#7915885)

When I worked for a library I noticed a log of files with red ! as their icons. I determined that they must be erorrors or duplicates. So I removed them. Turns out that in windows 95 a red ! means that it is a critical system file.
And the library did not have the system source media anymore so we spend the next day looking for any machines with a similar version of the deleted file and moveing them back by hand.

DB + Audit Trails (5, Funny)

Usquebaugh (230216) | more than 10 years ago | (#7915886)

Back in the mid 80s I was a jnr op on an old mainframe. Not much disk space so we used to save old audit trails to tape and remove them. Another pertinent fact is the DB starts UDX* and the audit trails start UDXA*

I wonder what might have happened if a certain jnr op had not being paying attention and thought he knew it all.

Yep, there goes the audit trails and the database :-( God knows why they kept me around.

Posting on Slashdot (5, Funny)

Mr. Piddle (567882) | more than 10 years ago | (#7915898)

"What is the biggest technology related mistake you have ever made?"

Statement by Slashdotters after the supoenas start rolling in: "Posting an admission of wrongdoing on a semi-anonymous public forum, whose owners will most likely cooperate with law enforcement when asked about an admission of wrong doing in a semi-anonymous public forum."

Packard Bell (1)

etymxris (121288) | more than 10 years ago | (#7915900)

First computer, got it in 1993 or so. Still had it sitting around as recent as a month ago, tried to boot it, and it failed. Finally tossed it. Not too surprised. It had trouble from day one. Most significant was the bad 8MB RAM module that couldn't be removed because it was soldered on the motherboard.

rm (0, Interesting)

Tirel (692085) | more than 10 years ago | (#7915928)

rm -rf * in the wrong directory. god that sucked, i lost weeks of work. been keeping daily backups since then and aliased rm to 'rm -i'

Re:rm (-1, Flamebait)

Anonymous Coward | more than 10 years ago | (#7915997)

no kidding. I wish the POSIX designers would have made rm ask you if you wanted to delete a file by default and have an override option for scripts and batshit insane people. It sure would have saved a lot of data over the years.

Re:rm (1)

Hungus (585181) | more than 10 years ago | (#7916066)

Heh last week I was transfering data through one of my media drives for archiving when the windows box I was transfering from crashed. Rather than reboot i opted to manually delete the open files sudo rm -r (insert a bunch of files here)I should have checked the command length as appeaently the command I copied into my terminal was clipped I would up erasing the entire drive. 180GB gone.

Worst Tech mistake I ever made? Using personal licenses on company machines.

Re:rm (2, Funny)

irc.goatse.cx troll (593289) | more than 10 years ago | (#7916189)

Atleast you did it in the wrong dir. I was working on adding another domain to /etc/apache/vhosts/(each domain gets its own file), and all of a sudden I notice the dir is empty. It wasn't empty when I started.. scroll up 4 lines and I see rm * in my buffer. To this day I still have no clue what I was intending to do, but from now on no more working on a server with customers without proper amounts of caffiene.

Re:rm (1)

squiggleslash (241428) | more than 10 years ago | (#7916208)

This counts as a dumb mistake more than a worst mistake but...

Never done that, but once was clearing out files and saw in /etc there were files like passwd~, passwd-, passwd.bak, etc, none of which contained any interesting or redundant information.

In a moment of madness that I still don't understand, I thought that "rm passwd*" meant "delete any file called passwd with something on the end of the name". Not a mistake I'd made before, and definitely not a mistake I've made since.

Fortunately it was a machine at home...

Re:rm (5, Insightful)

Brian Hatch (523490) | more than 10 years ago | (#7916382)

since then ... aliased rm to 'rm -i'

Bad plan. Now, the next time you log into a new machine you'll think that rm will be safe and will wipe out an entire directory tree again.

If you want to have a safe alias, use a different name! For example del would be appropriate. If you're not good enough to use rm correctly, then an old DOS command seems appropriate...

Re:rm ... I did this once (1)

baywulf (214371) | more than 10 years ago | (#7916386)

I had my windows partition mounted under a linux directory. I decided to move the mount point to another location so tried to delete the current mount point. I forgot that it was already mounted and ended up deleting the entier windows partition.

Re:rm (1)

jefu (53450) | more than 10 years ago | (#7916454)

Ah yes.

In the root directory on a unix machine many eons ago. I wanted to do "rm -rf something*" to get rid of some files that were created in / by some systems stuff I'd been doing. I managed to type "rm -rf something *" and hit return before I looked at it (it was an old clunky text-based console thing, in my own defense). Ooops.

It was not a fast machine though and I managed to catch it before too long - before it killed any user or important data anyway. It had killed some fun things like /dev and /etc and /bin though, but with the still running shell and some serious hackery and the network I managed to get the system back running well enough to restore things from backups (thankfully I did have recent backups).

Logging on to /. (5, Funny)

NickDngr (561211) | more than 10 years ago | (#7915930)

My biggest mistake was finding this website. I've wasted more time here that could have been spent doing my job and getting actual work done.

Everyone, listen closely. (1)

Ayanami Rei (621112) | more than 10 years ago | (#7916519)

You might be able to hear the mournful call of the endangered species known as "actual irony".

good thing we've had a backup - 1 month old (1)

rawbytes (737682) | more than 10 years ago | (#7915950)

One time we did "rm -rf /" just to test a backup on a server. Well it turned out the best backup we could get was a month old tape. It wasn't a production machine so we just had fun it.

Generic enough... (1)

Otter (3800) | more than 10 years ago | (#7915979)

A pretty basic one -- doing an ls of a different directory, forgetting I was actuall in /usr, and proceeding to rm -rf *. Pretty stupid, but in retrospect harmless. /home was unharmed, and it was just a home computer. Given that I work with equipment costing tens or hundreds of thousands, it could be a lot worse.

I'm reminded of when the metric/standard error lost the Mars probe. A labmate commented, "Boy, at least I'll never feel bad about screwing up a $20 experiment again!"

Failing to face reality... (2, Informative)

FreshMeat-BWG (541411) | more than 10 years ago | (#7915992)

...and force others to do the same thing.

Never, never, never, never commit to a schedule that is not realistic. If you know it isn't realistic before you get started, imagine what happens when you discover the unknown problems.

No matter how much that guy in marketing wants to meet his roadmap, he will not help you design, code, or test your product. If you are lucky, he will complete the requirements before you are supposed to ship the product.

A small one (5, Interesting)

FattMattP (86246) | more than 10 years ago | (#7916000)

After working on a bunch of NT servers all day I needed to make a quick change to our company's primary file server which ran Linux. After I logged out I hit control-alt-del and the machine started shutting down. About 30 seconds later the helpdesk switchboard lit up like a christmas tree. After working on the NT machines all day I didn't even think before I hit the keys. I guess I thought I was going to lock the screen or something. 15 minutes later I had the linux boxes configured to write to a log file when ctrl-alt-del was hit rather than rebooting. Lesson learned.

Thankfully, that's the worst I've done so far.

Re:A small one (1)

j-turkey (187775) | more than 10 years ago | (#7916168)

...server which ran Linux. After I logged out I hit control-alt-del and the machine started shutting down.

Been there, done that. One of my first tasks when provisioning a RH box is to edit /etc/inittab in order to prevent CTRL+ALT+DEL shutdowns. This is especially helpful in a mixed Linux/NT environment on a KVM switch :P

Re:A small one (0)

Anonymous Coward | more than 10 years ago | (#7916281)

Heh. Similar story... A co-worker managed to reset one of our tape robots by using alt+ctrl+del on the management consoles -- the things run OS/2 and take about an hour to do a full reboot and audit...

Damning evidence (5, Funny)

etymxris (121288) | more than 10 years ago | (#7916011)

Recently, I went to a work-from-home arrangement. Soon after I left, I got a call from several people at work asking me if I had emptied several SQL tables that were key to our QA environment. I swore up and down that I had done no such thing, and it was dropped.

The next day someone powered up the monitor to my old desktop (still at the office) and what did he see?

SQL Query Analyzer maximized with:
DELETE FROM IMPORTANT_TABLE

Query successful: 18,452 rows processed
(I still don't remember doing it.)

Re:Damning evidence (1)

Ianoo (711633) | more than 10 years ago | (#7916110)

I've done similarly stupid things when trying to fix live databases. Typing in things like "DELETE FROM accounts", then switching to another screen to find the account details, switching back, and watching in horror as the query executes without giving me the chance to enter "WHERE account_id = 184"....

Re:Damning evidence (1)

meta-monkey (321000) | more than 10 years ago | (#7916192)

That's odd. Generally you have to terminate the line with a ; or something, so it shouldn't process your query unless you tell it "yes, I'm all done typing." When I log into my mySQL server and do a "SELECT whatever FROM table" and press enter, it just goes to the next line, then I slap myself in the forward, hit ";" then Enter and it processes my query.

Re:Damning evidence (1)

etymxris (121288) | more than 10 years ago | (#7916360)

Line termination not required for MS SQL Server. (No, I don't use it by choice.) CTRL-E will work just fine, ENTER does nothing. And sometimes you just forget the where clause, or I do anyway. That's the only time I found rollbacks to be of any use--when cancelling a delete statement set against a multi-million row table in production that was was started without a where clause. Heart-stopping stuff. It wasn't me (I was just a witness), but had it not been stopped, it could have been the entire company's ass on the line.

Re:Damning evidence (1)

Gaijin42 (317411) | more than 10 years ago | (#7916511)

thats a feature of the editor you are using. Its looking for the ; to terminate the edit mode.

More GUI oriented editors dont have that feature/issue

Re:Damning evidence (3, Interesting)

Jerf (17166) | more than 10 years ago | (#7916460)

Similar to the if (0 == c) trick in C, I've been trying to train my fingers to type DELETE WHERE whenever I mean to type "DELETE". Then, I fill out the WHERE clause and only then go back to say what table to delete from.

This also gives you time to ponder the wisdom of first running a SELECT statement with the same WHERE clause and comtemplate whether you want to do this.

rm -rf * (2, Interesting)

FunkyRat (36011) | more than 10 years ago | (#7916023)

...five minutes later after coming back from getting coffee: D'oh!

I actually did this once... while logged in as root... at the top level in /home... on a production server. Thank baphomet for nightly backups!

Hopefully none of my clients are reading this. :-)

Buying a Maxtor HD (1)

RevAaron (125240) | more than 10 years ago | (#7916032)

I always had good luck with Maxtors, though I had only used old and small drives- 80-200 MB or so. When I was putting together a new computer for myself in 99, I thought I'd get another trusty Maxtor, a 6 GB. Pfft, bad idea. Thing failed in less than a year, taking all of my music with it; 5 years of dorky industrial music, recently copied over from a huge stack of ZIP disks. 100 songs.

grr.

Heh (1)

smoondog (85133) | more than 10 years ago | (#7916056)

Buying a PCjr. (Actually my dad made that mistake, and got it for me for christmas, about a month before IBM discontinued production. Fortunately, it had real keys at that point. Heh)

-Sean

Re:Heh (1)

dtfinch (661405) | more than 10 years ago | (#7916428)

I started on a PCjr. But in my case it was free and I got a second one for $25 which came with all the software and cartridges I wanted.

One that I saw... (5, Interesting)

Inexile2002 (540368) | more than 10 years ago | (#7916057)

None that I've done come to mind - I tend to make lots of little stupid mistakes rather than occasional huge cock-ups. But I had a client that had a CIO who was actively hostile to the idea of any kind of computer security what-so-ever. Waste of time and money for a made up threat he said.

They were running 13 servers at remote locations (and I mean remote, as in out in the boonies 4 hours from nowhere on back roads) and these servers were unpatched, had out of date or innactive anti-virus and were connected to the net via a combination of satellite and dedicated (always on) dialup. Their communications were secured with nothing more than Windows 2000's built in VPN.

Needless to say, my audit report told them that they had big beefy powerful angels on their side since they hadn't yet had a noticable intrusion. (They had no way of detecting one, but at least the servers weren't hosting porn sites.) I warned them that a virus or worm would come along though and knock the whole thing out. The CIO scoffed at my report, called me an alarmist and said that my opinions were right up there with the Y2K doomsayers.

When Slammer hit, I had described the vulnerabilities and outcome so accurately that this guy actually accused me of writing it myself. Took the whole corporate network down and they couldn't bring it back up until their techs visited each site. It took two teams seven days to get to all the sites. The company lost 6 business days, three customers and a months worth of transaction records.

Needless to say the CIO was demoted (they didn't fire him, which I consider itself a major tech mistake) and had me re-issue my audit report which they then followed to the letter taking every precaution I suggested.

didnt really hurt anything, but ... (3, Funny)

Merlin42 (148225) | more than 10 years ago | (#7916068)

When I was first learning linux/unix I installed RH5.something on my computer (cyrix 6x86 133+ iirc), anyway I was having weird issues with several programs so I decided i needed a fresh start, those darn dot files must be currupted.
So I typed:
rm -rf .*
This disk started churning ...
about 30 seconds later
the disk is still churning ... damn I must have a LOT of those dot files.
about a minute later .... *DOH*
CTRL-C
Where did all the files go? DAMNIT! I recursively deleted .. ( I was running as root, It was my personal box what could be the harm)
I learned my lesson very well:
CREATE AND USE USER ACCOUNTS!! DONT RUN AS ROOT IF YOU CAN AVOID IT!

blowing up my computer (4, Funny)

chendo (678767) | more than 10 years ago | (#7916077)

I was young (around 8 at the time, can't remember) and I was bored one afternoon. I started fiddling around with the back of the computer, the PSU, to be exact. The red button looked fun to play with.

It was on 220v. I turned the computer on. It worked. Then I tried putting it on 110v and turning it on. Nothing. Then I switched it back to 220v, turned it on, and switched it to 110v while it was on.

Boom.

Moral of the story is, trial and error isn't the best way to learn hardware, and don't throw water on the smoking PSU while it's still live.

a day's transactions... (0)

Anonymous Coward | more than 10 years ago | (#7916082)

i think i'll post this anonymously.

i work for a financial transaction company. i had just started and i was nursing along a system the previous programmer had written. the code had this "feature" where a nightly job would rotate its logs by just opening and truncating a file with a date encoded in it. it also had a bug where it would get stuck. so the first time we hit that bug, i just killed and restarted the job. and again. and again.

the problem is that the log file contained the days transactions. oops.

so i spent about 24 hours straight figuring out how to recreate the logs - in the end i did with the sole caveat that i could only retreive the date, not the time. luckily our bills only showed the date, not the time (which i set to noon that day).

ah, stress? what stress?

obviously all code i write does not just blindly open and truncate log files. that was just a vague rule before, now i'm rather fanatical about it. plus i record important info in multiple places. disk space is cheaper than 24 straight hours of stress.

Really? I believe the opposite is true (2, Insightful)

Isao (153092) | more than 10 years ago | (#7916084)

The more experience I and my coworkers have, the fewer mistakes we make, and they are less severe than before. This is because we learn from previous errors, and apply those lessons to entire classes of problems, not simply the error itself.

I think the articles implication of "the more we learn, the less we think" is wrong.

Re:Really? I believe the opposite is true (0)

Anonymous Coward | more than 10 years ago | (#7916419)

We learn from our mistakes? Speak for yourself bitchtard. - Geccie

Blowing away a new database (2, Funny)

drkich (305460) | more than 10 years ago | (#7916086)

Back in 1998, we were working on site deploying a new product to a customer. The product required us to create a new database on MS SQL Server. Well because of the size of this database, it takes over 5 hours to create. We could not continue on with the deployment until this was finished.

Well when it finished, in a rush to get out of there, I accidentally deleted the database and had to restart the process all over again. Many a cow-orker was pissed at me. Had to stay an extra day to complete the deployment.

Getting a cheap power supply (2, Interesting)

trajano (220061) | more than 10 years ago | (#7916089)

I've lost my machine to cheap power supplies. The first time I thought was just a freak accident (blew the motherboard, CD drives, hard drive), since then I go for the Enermax and not some unbranded power supply.

not so bad -- but still stupid (3, Funny)

j-turkey (187775) | more than 10 years ago | (#7916096)

So this wasn't a production machine I screwed up or anything, but I'm still a moron.

I had a Linux workstation that was ultimately adopted by the development group I worked with in the late 90's. Anyway, for some reason I needed to make a boot disk from an image. For some other reason, while typing in my command line, I was thinking fd0 but managed to type hda. So my line was dd if=/wherever/whatever.img of=/dev/hda.

Anyway, before looking at what I had typed, I hit enter. About 2ms later, I glanced up at what was on the screen and exclaimed something along the lines of "holy fscking shit!" and simultaniously hit a ctrl+c. Interestingly enough, the drive still kind of worked. I tried copying the contents of the disk over to another device, but I found that with each command - nay, each disk access, the filesystem would disintegrate further. I was able to save /home -- but I otherwise had to reOS the system.

I guess I've done much more stupid things with production machines -- but these were better machines, with storage on a NetApp NAS, which all had snapshots, so recovery was nearly instantanous.

These are not things that I include on my resume. (So -- anyone want to hire a disaster waiting to happen?) ;)

choose good mount point names (0)

Anonymous Coward | more than 10 years ago | (#7916102)

mv some.file /dev/hda1

no wait, i meant /mnt/hda1!

aw crap.

my own list (1)

mooingyak (720677) | more than 10 years ago | (#7916118)

These are partly the fault of the company, as the development/qa/production all occur on the same machine, but anyway, here are a couple.

I deleted a client's production database. I got lucky with this one, since even though it was a major client, the backup was 6 hours old and they were only using it for the last 90 minutes or so.

When experimenting with how to use the fork() system call, I wrote a program that was more or less equivalent to:

int main(void)
{
while ( 1 )
{
fork(); /* do stuff */
}
}

which brought the server (production) to a screaming halt. (for those not familiar, this will basically spawn processes indefinitly. We had to reboot).

Playing soundfile on remote UNIX box (5, Funny)

GuyMannDude (574364) | more than 10 years ago | (#7916121)

Oh man. So I was a grad student, right? I was always trying to portray myself as a very serious, dedicated student to my thesis advisor. And he had the fastest computer in the department (a Sparc10!) and he gave me permission to use it for batch runs. So I pretty much kept one of my xterms as a remote terminal to his machine.

Anyhow, one day I found this funny .au (sound) file and wanted to play it for my office mates. So I did a 'cat naked.au > /dev/audio'. Nothing happened. So I turned up the volume and tried it again. Still nothing. Then I screached in horror! I was typing this command in on the xterm I use for my advisor's machine! Sure enough, two seconds later an email comes trickling in from my advisor stating 'Please note that you are logged into my machine so your sound file is coming through my speakers.'

So what was this sound file that I had inadvertently played for my advisor?

Butthead: "Whoa! Naked chicks!"
Beavis (excitedly): "Yeah! Naked chicks! Naked chicks!"

GMD

this one time, at band camp... (1)

Tumbleweed (3706) | more than 10 years ago | (#7916125)

Okay, so "back in the day" (Amiga!), I got this really spiffy new floppy disk copying program, and decided that would be a good time to make backups of all my floppies (no HD back then). So I fired up the new copying program, and made backups of all my floppies.

Unfortunately, I hadn't taken quiiiiiite enough time to learn how this new copy program worked - it LOOKED pretty easy to use, but, well...no.

Instead of making backups of all my floppies, it had reformatted each of the floppies I put in to make backups OF, and formatted the 'copies' I thought I was making, thus wiping out my entire floppy collection.

*sigh*

Copy that floppy! (2, Funny)

Baron_Yam (643147) | more than 10 years ago | (#7916256)

I did something similar on my beloved C=64.

I borrowed a game from a friend, and wanted to copy it. Of course, it had the classic 'deliberate bad checksum' anti-copy protection, which meant nothing more than loading a disk copying program that would handle it.

About half way through the first phase of copying, it suddenly dawned on me that I was using my disk copying floppy as my destination disk. I immediately pulled it out of the drive, thus ensuring I had neither a copy of the game nor a copy of the software required to try again!

Not me making the decision... (1)

pp (4753) | more than 10 years ago | (#7916143)

But I did feel a bit stupid watching my school spend $160/box to roll out 16-bit Microsoft TCP/IP for WFWG 3.11 on all of the machines. A week after the order was made, a free 32-bit beta that worked quite a bit better was announced :-(

One of the worst personal mistakes is when I installed Linux 0.98 from the boot/rootdisk combination to my harddrive (previous versions I had to use from floppy due to missing support for my scsi adapter) I had a partition setup for it and everything. When the thing asked where I wanted to install, I answered /dev/sda instead of /dev/sda2 :-( (where sda1 was my DOS partition with code I didn't want to lose of which I had no backups :( )

Of course, that episode made my transition to Linux as the primary OS a lot faster since I had to restart those projects from scratch and started using gcc instead of borland while I was at it :-)

Cisco Routers (1)

eric2hill (33085) | more than 10 years ago | (#7916186)

I was planning an update to our global network to convert from RIP to OSPF so we could do some trivial load balancing.

Step 1: I telnetted into our core router and turned off RIP.

Step 2: Turn on OSPF.

The problem was that turning off RIP first killed all of our traffic world-wide. Oops. 10 seconds later OSPF brought the network back up. Sigh.

FoxPro-based MRP & Bad Networking (2, Interesting)

^chewie (65165) | more than 10 years ago | (#7916190)

I have two, both at the same company. I was hired on as The Tech Guy(TM) at a local OEM Manufacturer. They were willing to take me on w/limited experience but my pay reflected it. My first job was to replace their existing DOS-Cobal Manufacturing Resource Planning (MRP) software before the Y2K problems hit. The original software company wasn't supporting the old version any longer and the Mfg was getting too large for the program. They looked at a number of demos that were slow and painful, but they decided to try a "favorable" application (See also: cheap).

My mistake was to give the techie "thumbs up" under pressure. I folded to the "We needed this yesterday" argument despite my misgivings about the software. I paid for that mistake for the next year in slavish tech support. We became the software company's test bed as we found bug after bug. The software "worked", but operator efficiency dropped, and uptime was sub-optimal. "Customization" caused problems, etc., etc.

The second mistake I made was to attempt to use VPN over Broadband with Citrix MetaFrame. Although MetaFrame was a pretty secure and slim protocol for remote desktops, the Internet provider on the remote site had horrible latency problems and was run by a group of amatures. I should have stuck with the original Sprint frame relay proposal.

Morals of the story: don't let PHB push you into a solution you don't trust, and when network reliability is important, pay for assured quality of frame relay.

My Commander told me to kill the network (5, Interesting)

Perdo (151843) | more than 10 years ago | (#7916200)

I was a young pup in the Army, during a training exercise. My Commander told me to kill the network, to "simulate" it's loss. We were operating a frequency hopping radio network, which of course is based on time. As the master node, I controlled the time. I pumped my transmitter to full power, and slowly pulled the stations that could recieve my signal out of time. Lowered power, pulled a smaller number of stations even farther out of time. Wash, rinse, repeat.

Commander thought I was brilliant, and so did I. I had fractured our network into at least 10 different domains. No one could talk to anyone, effectively "simulating" an enemy jamming attempt. It would take hours to restore the network, with many mad commo guys having to drive about with Pluggers, early GPS devices, to restore each radio to propper time.

Then a tank flipped. Someone died. No one could call for help. I am so damn smart.

No moon black, At 2 in the morning, in an upside down tank, the gunner figured out how to put his radio in plain text to call for help. It took him almost half an hour.

rm -f fstab (1)

=weezer= (180393) | more than 10 years ago | (#7916202)

A couple of years back (using a Mandrake distro that was still basically Red Hat with some changes) I was messing around with the fstab file, trying to get a cdwriter to work, and decided that I had screwed it up beyond repair. Since I was coming from the "Wonderful World of Windows" I expected these files to autogenerate themselves on bootup (how? why? etc etc). So I deleted the fstab file . . and upon reboot found that, no, the absence of an fstab file is not a quick way to have a new one generated.

worst mistake ever. (1)

MoOsEb0y (2177) | more than 10 years ago | (#7916203)

Posting your worst tech mistake ever on slashdot and forgetting to check "Post Anonymously".

In a K-12 school... (1)

mrscott (548097) | more than 10 years ago | (#7916221)

I worked in K-12 for a few years as a network engineer and programmer (weird combo, but's served me well)

The particular district I worked for supported three school districts on a single Data General minicomputer. This meant three separate student databases. When we wrote new apps, we would install the app and then create a symbolic link to the student database for which we were installing it. In this way, a single new app could be easily rolled out to all three.

Once... (just once!), I rolled out the new app and linked to the wrong student database. Without remembering thatI had changed directories, I deleted the symbolic link to the student database... or so I thought until the phone started ringing. I had deleted the entire student database - not the link.

Fortunately, we had a good backup from the night before and this had taken place in the morning...

The days of the big-blue-paperweight... (1)

fstat(pipe) (147352) | more than 10 years ago | (#7916223)

Not really a tech blunder but...
Many years ago when I was a operator of an IBM 370 MF, I was showing a junior operator around the system console. My famous last words were "never, ever, ever press this button," as I proceded to depress the system halt button. Alarms went off, managers came running into the room. It was a mystery to all but me and the junior. We still laugh about that.

-Dumbass

cd /etc (1)

Fizzl (209397) | more than 10 years ago | (#7916228)

rm -f * ~

(Should have been 'rm -f *~')

Re:cd /etc (1)

Lord Bitman (95493) | more than 10 years ago | (#7916375)

I really don't see why rm doesnt have something built in that sees you type rm -rf / and just prints out a little message: "what, do you think I'm fucking stupid? No, I will not do that. (dumbass)"

Debugs on live routers (0)

Anonymous Coward | more than 10 years ago | (#7916230)

I once inadvertantly did 'debug ip packet' on a core router, at a service provider that shall remain nameless (posting AC too to protect my ass ;)
Obviously the thing crashed before me plus a couple of colleagues that were working with me on this box. All of us were all like, 'ooops' or 'shit...' The router was configured with something like 20 BGP peers, carrying multi-gigabit internet traffic accross one of the largest East Coast backbone.

Lessons learned: targeted traffic debugs (against an ACL), disabling console logging (only buffered) before launching heavy debugs.

ugh (0)

Anonymous Coward | more than 10 years ago | (#7916234)

installing and using Redhat 6.1 with Gnome.

I got to use the rm * -fr command though :)

I flooded the building. (2, Funny)

Futurepower(R) (558542) | more than 10 years ago | (#7916237)

Not about computers, but: While working for a Physics research lab, I made a laser water jacket without a bulge at the end of the inlet pipe. The water pressure rose at night, the tubing slipped off, and the 2nd floor and part of the first was flooded, including expensive test gear like oscilloscopes.

Lotus Notes... er.. (3, Funny)

zonk the purposeful (444367) | more than 10 years ago | (#7916269)

Working as a consultant I turned up at a new customer (moderate sized pharmacy) to see what they needed. Walked in, all confident, the local tech guy met me, and I asked to look at their server room (I always liked seeing the hardware).

Anyway, as we are standing there, I think, well lets see how many users they have, so I ask if I could look at the Name & Address book. Opened up the people view, hit Control-A to see the count at the bottom of the screen of the number of records. Unfortunalty it was a very small compaq keyboard, hit delete as I turned to the local tech..

CISCO access lists (1)

nocomment (239368) | more than 10 years ago | (#7916301)

I was working on a cisco access list one day, and was working on blocking IM clients per my manager. I tested it when I was done and sure enough, it blocked the clients, they could no longer log in. Satisified with myself I went to browse to slashdot. "hmmmm Slashdot must be down" I thought. So I tried somewhere else, maybe my computer is having problems. Then the IS phone started ringing off the hook. Dammit! Everyone is down. Nobody can do anything. Email is down, Web is down, VPN is down. I went to go look at my access list, but my terminal connection to cisco wasn't working either. Walked back to the server room, and rebooted the router (I never EVER save to nvram for at least a week). Everything came back online. I went and looked at my access list and forgot the allow rule at the end. All cisco access lists have an invisible "deny all" at the end, and I just forgot to say "allow all" oops.

The end of the day tally? at least 7 locations and 2 states.

deleting company's intranet home page on 4th day (0)

Anonymous Coward | more than 10 years ago | (#7916303)

Luckily I was able to reconstruct it, pretty much from memory and using other pages.

yep. good times.

Years ago, I once put together an html prototype app that had bogus links href'd as "xzy" or "xxx" - it seems that around that time Netscape started doing you the favor of embedding it in www.-.com, so a curious user found himself at a porn site.

Actually, he was a consultant from a competing company, and he made a *huge* deal out of it, cc'ing the client's department heads and VPs. There was a big uproar for about an hour, but in the end, no one really cared, and the other consultant came out looking like an grandstanding byotch.

Smells like...chicken? (0)

Prien715 (251944) | more than 10 years ago | (#7916319)

My friend and I were attempting to put together a computer for him about a year ago. The first motherboard we got was faulty (couldn't get a post), so we got a new one. The first few times we tried it we got some system beeps, so we looked them out and got rid of them. Finally, the bios screen came up and we both threw up our arms in jubilation, then the screen went black like it was shut off. I asked "I didn't shut it off did you?"
"No"
"What's that smell?"
"Hrmm...looks like the fan's loose. Oh well, I guess I fried the processor"

How about a beowulf cluster... (1)

brsmith4 (567390) | more than 10 years ago | (#7916328)

Actually, this was fairly recent:

The Chemical Engineering Department at my university purchased a 42 node rackmount beowulf through my department (well, the one I work for), the Research Computing Department. We were to assemble the cluster and house it in our server room.

Since my boss was busy working on a visualization project and my co-worker was out sick, I was handed the whole job. I decided that the best way to organize the cluster would be to put the 42 nodes in one rack and the head node, switch, and UPSs in the other. Well, when I put the 42 nodes in the rack, I had forgotten to drop the anchors at the base of the rack. The wheels on the left side at the base gave out under the weight (each node weighs in around 40-45 lbs) almost causing the whole thing to fall over. I almost trashed a $100k beowulf because of a stupid mistake.

Luckily I was able to fix the rack and rearrange all of the nodes before the guys at Chem. Eng. came to inspect. That would have been the end of my job.

CD caddy (1)

dtfinch (661405) | more than 10 years ago | (#7916341)

I stuck a bare CD into a drive that required a caddy, before I knew that kind of CD drive existed. This was at school in the 7th grade (I'm a college senior now). If anyone had seen it, there would have been an uproar, because I was a well known, but not well liked (at the time) computer nerd. As I was too rushed to get it out to think carefully, I committed another foolish act by fishing it out with a paper clip. Luckily I didn't cause many scratches.

Poweroff the RAS (1)

jmlyle (512574) | more than 10 years ago | (#7916343)

As I got home form work, I got a call from the company president saying that there was a power failure in the neighboorhood and all of the UPS'es were going. We didt't have any intelligent processes, like auto shutdown, etc, so he wanted me to remote in and safely poweroff the production and development servers. I knew there was a time limit, because we were stressing the UPS'es as it was, and the power had already been out for a while.

I got in through the firewall and started ssh'ing to various machines to poweroff. Unfortunatley, at one point, I exited out of one shell and ran poweroff before loggin into the next. Low and behold, I was powering off the machine that I was connecting through. DOH!

Luckily, the power did return shortly, and the ones that I didn't get to survived long enough to stay on UPS.

Oooops. (4, Funny)

Jasonv (156958) | more than 10 years ago | (#7916385)

I was doing phone support for a national bank in Canada. One of the problems we routinely had was a connection would freeze-up on a teller's terminal in one of the 1000s of bank branchs across the country.. We'd have to go into a program running on our AS-400 and reset the connection. On the odd occasion it wasn't just one terminal but serveral at the branch. We'd have to get all the tellers to exit out of their terminals for a second, then, in the program, we'd esentially hit the 'back' button, be up one level so we saw all the connections by bank branch instead of by terminal, hit 'backspace' to send the command to reset the connection and then 'y - enter' to confirm.

I got one of these calls, and I went one level up the tree, got distracted by something, and without thinking hit up-backspace-y-enter, going up two levels in the tree instead of one. This reset all the connections for the whole network, to all the banks, all across Canada.

Every phone in the call center started ringing. Every LED that could flash red did so. Everyone in the call centre looked around frantically. I looked at my terminal and almost died on the spot.

Not only had I reset all the terminal connection, but trying to bring them back online flooded the network so as soon as they tried to come back up they all went offline again. It took several hours to get things stabalized and the banks could start serving customers again.

Fortunatly my boss was a decent guy. He saw it as an accident and something that no one should be able to accidently do. The command to reset the entire network was modified so you had to type in your password to confirm, instead of just 'y-enter'

Directories named '*' (1)

Fished (574624) | more than 10 years ago | (#7916389)

Once in college, many years ago, drunk on the power of UNIX and beverages that I can't recall, I decided it would be clever to create, as root, a directory named '*' in the home directory. The following morning, hung over but still drunk on the power of UID 0, I correctly decided that this was a stupid id and ran the obvious command:
rm -rf /*
Then, I went looking for coffee.

Ooops. So, don't drink and root. Important safety note.

Worst...Tech...Mistake...Ever (3, Insightful)

Fortunato_NC (736786) | more than 10 years ago | (#7916393)

(comic book guy voice)

By far, my worst tech mistake was dropping out of college to take a full time job as an outsourced computer admin. Not having my degree has kept me from being competitive for better jobs with larger companies.

I love job now, but I don't have much room to grow, being as I'm the top IT guy in a 70-person company that's family owned (and I'm not in the family). I'm working on finishing my degree now so that when the time comes to move on, I'll be able to find jobs that have room for growth.

Worst? (0)

Anonymous Coward | more than 10 years ago | (#7916401)

Forgetting to back up my system before installing a new OS on the HD 0 (when I meant to install on HD 1).

Doing work twice must be better than once.. (2, Interesting)

tickticker (549972) | more than 10 years ago | (#7916410)

How about 5 times?

in 2000, a co-worker was migrating a large Catholic Diocese, one of the top ten say, from Novell to Microsoft (I still don't know why) as I had somewhat purposefully(on my part) been asked not to come back for a while (but that's another, dumber story).

Anyway, not having done any such migrations before, after thoroughly RTFM, he set up, almost entirely correctly, the migration service and began moving users. The syncing tool was set to run just before backups, so that the backup would reflect that days migrations and updates.

It was supposed to go like this: copy all files from the Novell directory, nightly, to the new user directories on microsoft shares unless the Microsoft file was newer (hence indicating that user was migrated) and eventually all users, over the course of a week, would be migrated and the sync turned off. everyone transparently suddenly works with microsoft shares and la di da off they go.

It was an excellent plan with the exception of forgetting to check the little box that made sure that newer files were not overwritten with the old ones from the (now defunct) novell servers during syncing. So every night the old files would overwrite then newer ones. People started to complain about the third day that their changes to documents and such weren't "sticking", and on the last day of the migration, we figured out what had happened.

So every night, before backups, the newer files were being overwritten and then backed up. This included the Accounting, Newspaper articles, judgements, spreadsheets, EVERYTHING. For a whole week, 1600 users lost their data and it wasn't backed up on purpose. Oops. Funny thing though, our company kept the account and what remains of that company still works on it to this day!!

What happened to the co-worker? Well we all just kinda laughed it off and that 19 year old kid became the second youngest CCIE up to that point in time, and a year later got his second CCIE in security and is making comfortably north of 120k/yr now.

-- This sig has a cholesterol count of 680... higher is better right?

Ahh, stories. (4, Interesting)

Zapman (2662) | more than 10 years ago | (#7916418)

My best singke mistake was after a long night of re-installing an updated version of solaris on a SparcServer 2, I needed to clear out the /tmp dir sor some stupid reason. So, I did the old: "mkdir newdir ; mv * newdir"

I wasn't in /tmp. I was in /.

My next command was 'ls'. It returned: unable to find /usr/lib/libc.so.0

AAAAARGH!

I now know how to solve that under solaris. Under /usr/sbin/static there are 5 statically compiled binaries: cp, ln, mv, rcp, and tar. /newdir/usr/sbin/static/mv /newdir/* / would have fixed it.

Ever since then, my prompt has had my current directory in it. That experience certainly made me more careful.

Better (or worse) was when a stupid service rep came in to replace a bad CPU on a sun e10000. The idiot shut down the sub-system, and powered off the board correctly. He then managed to pull out the wrong board, despite the blinken lights. Of course it was the peoplesoft domain. Running year end reporting.

AAAAARGH!

Ouch (0)

Anonymous Coward | more than 10 years ago | (#7916421)

Freshly out of college I linked ls to l. But I reversed the parms to ln and linked ls to nothing. Not fun. Trying getting around Unix without ls.

tar sun4u sun4m (1)

Michael.Forman (169981) | more than 10 years ago | (#7916433)


I was a newbie sysadmin who didn't fully grasp the concept of the tar command. I untared an entire /usr/X11 directory ontop of an existing /usr/X11 directory. The painful part was that the distributions were binary incompatible -- one was compiled for sun4u processors and the other for sun4m processors.

I knew I made a mistake when exclamations, gasps, and quizzical mutterings began to fill an otherwise quiet graduate laboratory. Before I had a chance to fully grasp what I did, my three supervisors walked in the door, having seen my command scroll across their syslog terminals.

Michael. [michael-forman.com]

Rack mount chassis and power cables (1)

Drunken_Jackass (325938) | more than 10 years ago | (#7916440)

One time I pulled out a 1U rack mount chassis from our rack only to hear it power down as it got about halfway out. When we installed the system, we didn't use the cable management system in the back to snake the power cable through, so when the chassis was pulled out to install a hot-swappable device, it yanked the power cord out.

Luckily it wasn't a really important server.

Lesson learned: Use cable management systems, or give yourself enough slack so that when you need it, you'll have it. No sense in having hot-swappable components if you power down the system when you pull it out of the rack.

Compressed a live SYS1.LINKLIB on an IBM m/f (1)

Dammital (220641) | more than 10 years ago | (#7916453)

Years ago (okay, 30 damn years) as a wet-behind-the-ears systems programmer wannabe, I ran out of usable space when adding a program to a system library. Fine, I said, I'll just "compress" the library (IBM object libraries of the time used to contain holes where programs had previously been deleted; it was necessary to intermittently defragment these libraries).

Unfortunately, the library I defragmented was SYS1.LINKLIB -- out of which most of the operating system was executed as well as the defragment utility itself. Very quickly after the utility started moving programs around on the disk the operating system ground to a halt.

The real systems programmer, who had been up all night, was NOT amused. He had to come in and I helped him perform a DR. The mainframe system was down all day -- I wasn't very popular.

Somehow I didn't lose my job. In fact, I eventually came to own technical support and operations there. But 10+ years after my screwup people still liked to remind me about it. Guess they figured it kept me humble.

DEC unix != linux (1)

JBv (25001) | more than 10 years ago | (#7916473)

I had never used anything besides unix. Once a brand new alpha 500 arrived for me to play with on my first week as a PhD student.

While trying to cope with stupid licence restrictions, the fact that $HOME for root is / and that rm is non interactive, I accidently deleted (I think) the kernel of the machine. The fact is thta it wouldn't boot!!!!

Sweating like a pig I tried to explain to my supervisor and unfriendly IT guro how after 3-4 hours of unpacking the most expensive computer in the lab was dead.

Not my mistake, but funny... (1)

Will_Malverson (105796) | more than 10 years ago | (#7916481)

I was working at a company that does hardware testing in the USA (110 V electricity). I neeeded to test something with USB 2.0, and none of the computers in my little test area had it. I asked around, and somebody else had one. As I carried it back to my area, I noticed that it was a Compaq model 1234.uk (or something like that).

I plugged it in, the little green light came on, the fan spun up, and I noticed the '220V' sticker right next to the power socket. So, I promptly yanked the plug and hoped that nothing bad had happened. After a second, I shrugged, figuring that putting in half the power it was expecting probably wouldn't do anything.

I walked out and found a 110 -> 220 transformer. I plugged it in and plugged the computer into it. Again, the light came on, the fan spun up, and...

POW!

Suddenly, it was very quiet, because everybody quiets down when they hear a loud noise. It was especially quiet because all of the computers in the room were now shut off. A second later, I hear someone in the next room over ask, "Hey, did your computer just shut off?".

At this point, people are looking at me, because I was the source of the noise. I promptly (and of course, futilely) yanked the cord again.

About this time, I noticed that the power supply didn't have a 110 <-> 220 slider like most of them do. I looked more carefully, and found it. It was set to 110. I had missed it the first time because it was CONCEALED UNDER THE '220V' STICKER!

It turned out that the room I was in was almost overloaded, and that computer blowing out was enough to do it in. We rerouted some extension cords and all was well.

Beware of Undo! (1)

Asprin (545477) | more than 10 years ago | (#7916482)


You know, [CTRL]+[Z]?

In Windows Explorer, it undoes the last file operation....

...well, it undoes SOME file operations, but not others, as I found out the hard way:

I was at a client's site a few years ago moving some data files around on their NT server and archiving old things that weren't needed anymore. As a part of this, I renamed a "particularly named" folder and hit [ENTER] just as the thought occurred to me that I needed the exact spelling of the original folder name before I changed it. So, without thinking I hit [CTRL]+[Z] to change the name back figuring I could just copy the name to the clipboard and rename it again. HOWEVER, instead of un-doing the recent "folder rename" operation, it undid a much earlier "folder COPY" without telling me which folder or where it was located!

Luckly, I was able to retrace my steps and figure it out well enough to put everything right, but NO MORE HAVE I *EVER* [CTRL]+[Z]'d in Explorer again!

I ruined a phone book (2, Interesting)

seanmeister (156224) | more than 10 years ago | (#7916488)

I work for a telephone directory publisher. A few years back, we were pushing a deadline and the man was not happy with the completeness of zip (postal) code info in the book. I purchased a new zip coding utility, ran it against the listings, and told the production dept to proceed with pagination, thinking that the army of proofreaders we have would notice any errors introduced by the new software.

I mean, what, I'm supposed to proofread the entire phone book by myself?

Anyway, the software used some kind of crazy soundex routine to "fix" addresses that it wasn't able to resolve, and thousands of people ended up with completely incorrect address information. The book went to press, was distributed, and a day later the phones were ringing off the hook. We had to pick up the old books, fix the data, schedule more press time (no easy feat), re-print, and re-distribute.

Total cost to correct was around $1M, got my ass chewed royally, but managed to keep my job anyway.

Must be doing *something* right!

Ghosted the wrong drive (1)

Philosinfinity (726949) | more than 10 years ago | (#7916493)

One time I was installing a new hard drive for a customer. He wanted the data transferred from the old drive to the new one and the old drive discarded. The company I worked for had just obtained a copy of Ghost and it was our first time using it. I mixed up the two drives and copied the larger (new) drive to the smaller one and destroyed all the client's data.

Making a RAID disk "online" (1)

SpaFF (18764) | more than 10 years ago | (#7916505)

We had a drive in a RAID5 container go bad at work a few years back. This was a raid controlled by an old Mylex DAC960. A guy I worked with went to replace the drive. He powered the machine down, took out the bad drive, put in a new spare, and powered the machine back up. In the controller setup he was presented with two options: rebuild and make online. Well he chose "make online" instead of rebuild. This caused the controller to render the raid volume completely useless. He chose poorly.

Low-Level format (1)

VisorGuy (548245) | more than 10 years ago | (#7916531)

One time I accidentally low-level formatted the wrong hard drive. I wanted to do the 1st (Primary) hard drive and the BIOS started it's drive enumeration at zero. So of course without thinking I put in a 1 instead of a 0.

I think the most important thing that was on it was my collection of digital music that I had spent over 1.5 years downloading from random FTP sites (this was before Napster) via a 28.8 and later a 56k modem.

Fortunately, a friend had a recent copy of my music from our recent LAN party.
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