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Type in the exact number of machines to proceed

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Re: Type in the exact number of machines to proceed

#281

Post by andreareina »

mjevans wrote: post #273
tatersolid wrote: post #270

Earlier quoted context omitted.

For the rare but critical manual SQL mod our common safety measure is to wrap every DELETE or UPDATE in BEGIN TRAN...ROLLBACK TRAN first. Run on test systems or snapshots multiple times, checking the result inside the transaction. Finally, change ROLLBACK to COMMIT only when you are positive all is well.

IIRC (without checking the manuals) data-definition commands might not be covered by such transactions: such as altering, dropping tables and possibly truncates.

PostgreSQL is quite good about DDL being transactional. So I was surprised (tbf, I shouldn't have been) when Redshift autocommitted after a TRUNCATE. But DROP TABLE is transactional, go figure.

Re: Type in the exact number of machines to proceed

#282

Post by D-Coder »

temporallobe wrote: post #173

This is similar to a UI solution a colleague and I came up with. The action the user could kick off was unstoppable and irreversible (a large batch job), and it seemed like even a confirmation prompt was too easy to simply click through. So we had the UI present a modal dialog asking the user to type in a specific word in all caps to confirm the action. Worked like a charm.

I did a similar thing with a Star Trek program many years ago. One of the commands (22? 23?) was to detonate the warp engines in the hope of taking the enemy with you.

After hitting the wrong number once, I added a confirmation that presented a random six-digit number that you had to enter before it accepted the command.

Re: Type in the exact number of machines to proceed

#283

Post by andi999 »

waterhouse wrote: post #195
blantonl wrote: post #21

Earlier quoted context omitted.

Watch and listen to pilots as they complete checklists. They point and callout each item, switch setting, etc.

I searched Youtube for examples of this. This is a little bit staged, but it seems to be a real checklist they're going through: https://www.youtube.com/watch?v=JG7SkOQDDt0 Though they're not perfect. They said that one pilot is supposed to read the item, the other pilot say the answer, and the first pilot visually confirm it; but at 1:42, I noticed the first pilot say "emergency exit lights", hear the confirmation,…

Routine is the killer. Have a look at the fatal maglev train accident in Germany. Service car was on the track. Presence of service car in service bay (and not on track) can be seen visually by operator (driver) in the control centre when turning head. (If I remember correctly)

Re: Type in the exact number of machines to proceed

#284

Post by dasyatidprime »

jlmorton wrote: post #180
brundolf wrote: post #127

Earlier quoted context omitted.

I've only been in the job field for six years, and yet: My first boss accidentally deleted our QA database, meaning to delete a local copy A later boss accidentally deleted our production database, thinking it was the clone that he had just made (which luckily we still had) Both of them were very experienced developers in their 40s. Nobody is beyond this kind of mistake.

War story time. Long ago, I worked for an interesting company that insisted on running its entire business on Linux desktops, all the way back between 1999-2002. Imagine running StarOffice/OpenOffice, Thunderbird, Netscape Navigator, etc, for your entire business back in 2000, including your executive team, marketing teams, everyone, most of whom had never even heard of Linux before. Anyway, this being Linux, everyon…

You probably knew this already, and there's probably better solutions if you're not in the manual sysadmin world, but after I did that on a personal machine a few decades ago (I think it was?), I got in the habit of using `--one-file-system` when doing major recursive rm operations that weren't meant to cross filesystems. Or `find -xdev … -delete` for anything more selective.

Re: Type in the exact number of machines to proceed

#285

Post by gomox »

abrookewood wrote: post #209
jlmorton wrote: post #180

Earlier quoted context omitted.

War story time. Long ago, I worked for an interesting company that insisted on running its entire business on Linux desktops, all the way back between 1999-2002. Imagine running StarOffice/OpenOffice, Thunderbird, Netscape Navigator, etc, for your entire business back in 2000, including your executive team, marketing teams, everyone, most of whom had never even heard of Linux before. Anyway, this being Linux, everyon…

That sinking feeling and cold panic when you realise what you've done. God that is horrible.

My favorite version is when that UPDATE or DELETE SQL query that you expected to finish instantly takes a few seconds before giving you your cursor back.

Re: Type in the exact number of machines to proceed

#286

Post by mcintyre1994 »

AWS sometimes does something similar to this like “enter the name of the thing you’re trying to delete to confirm”. I think it makes sense because you can have such a huge difference between how much you care about certain s3 buckets or CloudFormation deploys etc. In true AWS fashion it’s inconsistent between services though.

Re: Type in the exact number of machines to proceed

#287

Post by segfaultbuserr »

dgritsko wrote: post #2

Similar idea as GitHub's "type the exact name of this repository if you want to delete it" confirmation dialog. Maybe that's really what you want to do, but in case that's not actually what you meant to do, having a few extra hoops to jump through seems like a good idea.

Some disk management software also has "type the exact label of this partition to reformat it" to prevent accidental data loss.

Re: Type in the exact number of machines to proceed

#288

Post by giantDinosaur »

myself248 wrote: post #227
csmattryder wrote: post #8

I've seen this called "pointing and calling" [1], Japan's train drivers use the technique to force themselves to perform actions and take notice of the current environment. I personally took it to heart, it's a good system for forcing a cache miss in the brain - make sure you're on "database production" or "database localhost" etc. [1] https://en.wikipedia.org/wiki/Pointing_and_calling

Ever since hearing about point-and-call, I've started using it in the kitchen when turning on the stove. I used to destroy one or two pans a year by turning on the wrong burner, but it's now been about a year and a half and I haven't screwed it up yet. The knobs are labeled with a terrible little glyph meant to indicate which is which, and I've supplemented this with plain-english Brady labels "front left", "front ri…

I'm curious how exactly you managed to destroy pans. I've never destroyed a pan in my life, and take no particular precautions - is this a common thing? Is this more common with non-stick stuff or something?

Re: Type in the exact number of machines to proceed

#289

Post by Huggernaut »

jlmorton wrote: post #180
brundolf wrote: post #127

Earlier quoted context omitted.

I've only been in the job field for six years, and yet: My first boss accidentally deleted our QA database, meaning to delete a local copy A later boss accidentally deleted our production database, thinking it was the clone that he had just made (which luckily we still had) Both of them were very experienced developers in their 40s. Nobody is beyond this kind of mistake.

War story time. Long ago, I worked for an interesting company that insisted on running its entire business on Linux desktops, all the way back between 1999-2002. Imagine running StarOffice/OpenOffice, Thunderbird, Netscape Navigator, etc, for your entire business back in 2000, including your executive team, marketing teams, everyone, most of whom had never even heard of Linux before. Anyway, this being Linux, everyon…

This reminds me of a time when a colleague and I were investigating some persistent D-State processes that were occurring when container processes were being exec-ed.

Once on the box, we wanted to create a container with utilities in the fs but didn't want to download an image tarball or look through the rootfs layer directories for one to use, so we just bind mounted host root onto another directory, beside the config file we were using.

This worked like a charm. Until we rm -rf'd the config directory and deleted host root in the process.

In our case, fortunately the consequences were minimal as all workloads were stateless. The container scheduler moved all the workloads to other hosts and the host scheduler noticed this VM wasn't responding any more and rolled a new one. The whole thing resolved itself in about 5 minutes with no interaction from us - so that was pretty neat.

Re: Type in the exact number of machines to proceed

#290

Post by rcarmo »

This reminded me that a few years back I worked at a place where (notoriously) Puppet would occasionally go over some random box and remove access to people, just because.

Or to all the machines, on one occasion.

(It was actually some sort of race condition when we massively updated per-project access permissions and asked for SSH keys to be redeployed, but it was annoying as heck, and sure to happen whenever you really needed to access that particular machine.)

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