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What Does Your Dead Man's Switch Do? 310

LqdEngineer asks: "How many of you use or have used a Dead Man's Switch designed to perform some action if you don't check in for a certain amount of time? Recently, I decided to put one together using MySQL and some cron jobs, but I wanted to see what others have their switches set up to do in the event you fail to check in. E-mails to loved ones? Send encryption keys to friends/family? Hate mail to your boss? Has anyone ever been on the receiving end of the results of such a system?"
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What Does Your Dead Man's Switch Do?

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  • by P(0)(!P(k)+P(k+1)) ( 1012109 ) <> on Wednesday January 10, 2007 @03:31AM (#17536038) Homepage Journal

    From TFS:

    I decided to put [a dead man's switch] together using MySQL and some cron jobs . . . .

    I'll counter with my own ask-ask-slashdot: why would you use MySQL? It's only one more component to fail after you've expired.

    My advice: lose the extraneous components; and get a wife, too: they come with a redundant dead man's mechanism.

  • by TodMinuit ( 1026042 ) <todminuit@gmail. c o m> on Wednesday January 10, 2007 @03:34AM (#17536052)
    Blow up the building.
  • by ForestGrump ( 644805 ) on Wednesday January 10, 2007 @03:42AM (#17536088) Homepage Journal
    When I take my foot off, it slows the car to a halt. Just kidding, cruise control gets around the situation.

  • Halo. (Score:5, Funny)

    by headkase ( 533448 ) on Wednesday January 10, 2007 @03:44AM (#17536104)
    Duh. Activate the rings and release the black hole from it's omni-magnetic retainer so it can eat Earth. No traces left.
  • by green pizza ( 159161 ) on Wednesday January 10, 2007 @03:46AM (#17536108) Homepage
    My deadman's switch is programmed to create a series of new deadmen's switches, each more complex than the last.
  • by antifoidulus ( 807088 ) on Wednesday January 10, 2007 @03:46AM (#17536110) Homepage Journal
    delete all the porn!
    • Re: (Score:3, Interesting)

      by Garridan ( 597129 )
      Why? If it's illegal, you won't get caught once you're dead. Unless, of course, you believe in heaven & hell -- and from what I hear, God already knows, so hiding it won't do you any good.
      • I take it you're not planning on getting life insurance, because when you're dead, well, then who cares about the kids?
      • by LordEd ( 840443 ) on Wednesday January 10, 2007 @11:12AM (#17539528)
        The trick to the whole heaven & hell thing is acquiring people's souls. Go to a bar and you could probably convince somebody to see you one for a beer. I always state that my terms for a small loan of whatever is their eternal soul as collateral.

        Basically, if it turns out religion is right, you now have some negotiable material to barter with should you wind up going the wrong direction. If religion turns out to be wrong and you just fade to dust, then you aren't in a position to worry about it anymore either.
    • Re: (Score:2, Funny)

      by bofkentucky ( 555107 )
      You never saw the Man Show, they had a fake ad that in tone sounded like a life insurance spot, but the premise was, as a single guy you're going to leave shit behind your family doesn't need to see. If you have their service, Adam and Jimmy would come over and replace your den of filth, porn, and booze with a clean house, bibles and pictures of Jesus on the wall. My youtube-fu is weak, but it's funny shit.
  • by monkeypoo ( 981042 ) on Wednesday January 10, 2007 @03:46AM (#17536114)
    What happens when five years from now, after the thrill of having something like this setup, you forget to check back in? Now you've got passwords and emails going around saying you've passed on? I'm sure grandma will love that email. Why not just use a system that isn't triggered until your death certificate becomes available. Set it and forget it.
    • by Bazman ( 4849 ) on Wednesday January 10, 2007 @04:11AM (#17536234) Journal
      "Why not just use a system that isn't triggered until your death certificate becomes available."

      Such as? Maybe you can leave a sealed note with whoever has your will, saying 'in the event of my death please visit this web page', then give a URL, username, and password, the visiting of which causes a server-side script to run and delete all your pr0n, hate-mail your boss, put your low-numbered slashdot account up on ebay for the benefit of your next of kin, and so on.

      Of course you'd have to make sure that URL was secured....

    • by daeg ( 828071 ) on Wednesday January 10, 2007 @04:12AM (#17536246)
      Agreed. There is a much better dead man's switch available, and it's called a living will and a lawyer who has the legal authority to open your safe deposit box in the bank once you pass on. It even has generations of legal precedent to help defend against greedy family members.

      You can even set it up with your lawyer to have him mail things out once you're dead -- including your encryption keys, letters to family, etc.

      And yes, I have been the recipient of such a letter. Many such letters, in fact. My great grandparents both wrote letters to the family describing our family history going back to roughly 1550-1600. Instead of sending them to us and us inevitably losing them, they wrote them to their estate lawyer, who held them until they both passed on. They are great reading and have been far more valuable tracing family history than the Internet or any books or libraries have gotten us.
    • by arivanov ( 12034 ) on Wednesday January 10, 2007 @09:47AM (#17538372) Homepage
      I strongly suspect that the answer is about a slightly different form of dead man switch - the "fired man switch.

      There is only one possible recommendation to be said here: "Do not".

      First, your knowledge and capability are the best "dead" man switch you can have. If you need more than that you have failed in your professional objectives. Get real, sit down and get better at what you do.

      Second, what goes around, comes around. You never know whom are you going to meet in your next job. Even if you meant it to be a real "dead man switch", you never know whom are your descendants, students or friends going to meet in their next job.

      Third, if you leave a reasonable amount of time between the last check and firing the targets are likely to change, which will make the payload of the dead man switch misfire. You would either overdo it or fail to do it fully and leave traces. Either case is not in your favour. What may have been a harmless prank can become a crime which will be traced to you.

      So the recommendations are do not, do not and do not. Your will deposited with your bank or insurance company is a good enough dead man switch and you will be surely dead when it gets invoked.
    • by green1 ( 322787 ) on Wednesday January 10, 2007 @02:36PM (#17543314)
      that was actually my first thought as well... of course it didn't take long to come up with the solution, set up the same system to email YOU before it emails anyone else, if you've simply forgotten this will remind you and let you go check-in, and if you're dead it won't get a reply and will then go on doing it's business...

      I'm still not entirely sure I would set up such a system rather than simply writing a proper will and leaving the information with a trusted individual, however it is certainly not an insurmountable problem, and there could be benefits to such a system, if nothing else, some of the paperwork that people would need to settle my estate is on my computer, and I'd rather they don't spend a bunch of time cursing me for not having easy access to it while trying to both deal with the legal obligations and grieve at the same time...
  • I expect my Dead Man Switch to come back to life singing "I Heard It Through The Grape Vine" before keeling over again.
  • Too Effective? (Score:5, Insightful)

    by pyr3 ( 678354 ) on Wednesday January 10, 2007 @03:48AM (#17536126)
    I've always thought that a Dead Man's Switch held too many problems. Unless you have people that are 'out to get you' and your switch is your leverage, then it's not much use.

    What happens if you get into a severe accident and end up in the hospital without the ability to 'check in' with it? What happens if you are stranded at an airport with a snowstorm? What if you are stranded at a ski lodge in the mountains in the middle of a snow storm? etc...

    If you were ever unable to check in with the switch, then you would probably regret hate mail to your boss or other nasties that you had planned to send to people you hate. It would also be an unwelcome surprise for friends and family to get 'letters from the dead' just to find out that you really aren't dead. It would definitely be a detriment to you if you had it setup to donate all of the money in your bank accounts to charities....

    The Dead Man's Switch has too many if's in it. It makes more sense to just put together a will and make sure you entrust someone you deeply trust to execute it.
    • Re:Too Effective? (Score:5, Interesting)

      by Technician ( 215283 ) on Wednesday January 10, 2007 @04:21AM (#17536288)
      What happens if you get into a severe accident and end up in the hospital without the ability to 'check in' with it? What happens if you are stranded at an airport with a snowstorm? What if you are stranded at a ski lodge in the mountains in the middle of a snow storm? etc...

      Mine simply locks the encrypted filesystem if the power is interupted. A raid on my premisis while I'm gone locks things up tight. Forcing the door drops power. When I'm back, I can enter the encryption key and restore normal operation.
      • Re: (Score:3, Funny)

        by caluml ( 551744 )
        Forcing the door drops power.

        What the hell are you protecting there?

      • Re: (Score:3, Informative)

        by zebs ( 105927 )

        No use in the UK though. If you don't hand over your encryption keys you can go to jail.

        Good thing too. I am now safe from Terrorism
    • I instantly thought of this prior Ask discussion []

      "I'm a widower caring for my very disabled child. I have family who check in on me often, but not reliably, and not every day. How can I rig up a 'dead-man's switch' that will alert family or emergency services should something happen to me, so that my child can be cared for? Her medical needs are significant enough that being alone for even an hour could be fatal for her. We do occasionally get out of the house, so a GPS type cellphone and a heart-rate moni

    • Re: (Score:3, Insightful)

      by munpfazy ( 694689 )
      Not to mention: What happens if there's a software or hardware goof? Even leaving aside malicious attacks and the possibility of bugs in your code, who'd want to trust life-changing information to the system clock on a single machine?

      You could imagine hardening a system against some of the more obvious dangers. Using two severs in different countries which confer with each other before sending anything and which both contain part of the encryption key for your data would go a long way toward catching the
  • by Frogbert ( 589961 ) <frogbert@gmail. c o m> on Wednesday January 10, 2007 @03:48AM (#17536128)
    It's hooked up to my personal suicide machine.
  • by monkeypoo ( 981042 ) on Wednesday January 10, 2007 @03:51AM (#17536146)
    Why not make a system that, after you've passed away, pretends to be you from beyond the grave?

    Maybe it checks your email contacts (most people will know you've passed on of course) and sends out randomly generated messages about how great heaven is?

    "You'll never believe it! The Mormons were right!!"
  • by Schraegstrichpunkt ( 931443 ) on Wednesday January 10, 2007 @03:51AM (#17536152) Homepage

    [_] No Karma Bonus [_] Post Anonymously [_] Post Humously
  • False alerts (Score:4, Informative)

    by iMaple ( 769378 ) * on Wednesday January 10, 2007 @03:52AM (#17536158)
    I havn't had any false alerts thanks to another semi dead man's safety, which sends me an email 15 days before my actual switch turns on.

    I basically have 7 emails to ppl really close to me. One of my password go in one of those emails and that has access to all my email/personal passwords. I havnt put any banking data since I dont think thats going to be too difficult to get, if I am legally dead.

    My deadmans switch is a simple cron job and I need to reset it once every 3 months.
  • by Barny ( 103770 ) <> on Wednesday January 10, 2007 @03:56AM (#17536168) Journal
    1. Teleport without error to my own pocket dimension
    2. dispell all negative effects on me
    3. teleport a friendly cleric in to rez

    On a little more realistic scale, how about you make a will?

    IN THE EVENT OF DEATH EACH PERSON NAMED WILL RECEIVE THE ENCLOSED USB DRIVE WITH THEIR NAME ON IT... not overly difficult, and there are real legal comebacks if it is processed and you are not in fact deceased, instead of just looking like a tool.
  • by dbIII ( 701233 ) on Wednesday January 10, 2007 @03:59AM (#17536182)
    Usually the entire point is to run stuff so you can get hit by the proverbial bus and someone else can take over - or so that you can theoretically take an extended holiday at some point. A dead man's switch sounds extremely unprofessional and probably should get you fired no matter how unethical the rest of the workplace looks (unless it is emailing documentation of actual criminal activity to the relevant authorities - but you should be doing that in person anyway).

    I helped out for a few months in a place where the sysadmins and most of management had to be marched out the door by security for various expensive reasons. The place seemed full of dead man's switches but it reality was probably just a finicky cobbled together collection of systems that required intervention when cron jobs/scheduled tasks could have done it (and later did).

    Currently the stuff that is being trialed would stop and someone would have to look at the tape schedule - but I thought the whole idea of working as a sysadmin was to set stuff up so everything else goes smoothly while you are sorting out the problem of the day, trying out new stuff, or reading slashdot.

    • Re: (Score:3, Funny)

      The place seemed full of dead man's switches but it reality was probably just a finicky cobbled together collection of systems that required intervention when cron jobs/scheduled tasks could have done it (and later did).

      This leads to this observation: Any sufficiently finicky cobbled together collection of systems that requires intervention is indistinguishable from a Dead Man's Switch.

  • by pyrrhonist ( 701154 ) on Wednesday January 10, 2007 @04:01AM (#17536190)
    I wanted to see what others have their switches set up to do in the event you fail to check in.

    My switch nukes everything from orbit.

    It's the only way to be sure.

  • by LunchSpecial ( 1030924 ) on Wednesday January 10, 2007 @04:12AM (#17536242) Homepage
    If I don't check in with my Jewish mother every few days she'll go crazy and call everyone I might have once talked to.
    I didn't set this up, it was genetics.
  • The only cases I used one was to debug stuff that potentially locks the computer up. I.e. kill a process or reboot the computer after a certain time if nothing happens. Don't know if that counts....
    • by ebbe11 ( 121118 )
      That's commonly called a "watchdog" and is used quite a lot in embedded systems. I've even implemented one on a PC. It interfaces with a bit of custom hardware that can reset the PC in case the watchdog software also goes astray.
  • It send the contents of a folder to friends, family, media, governments, corporations, etc. (all defined in a list, or course)

    The contents of said folder include the most incriminating of information and encryption keys.

    Also, said folder may contain up-to-date security footage and audio taps.

    This tends to discourage the trigger-happy-brain-dead-mob types from doing anything painful.

    Now, in order to be most effective, this system is actually activated on servers across the world and distributes links and enc
    • This tends to discourage the trigger-happy-brain-dead-mob types from doing anything painful.

      OR, they could just grab you and take you to a secluded location (abandoned warehouse/cabin in woods/whatever), torture the information of your DMS out of you, use said info to disable your DMS, and then kill you.

      Now, you could get someone you trust to help with part of the setup work so that not all the information can be tortured out of you, but then you're endangering the life of that person as well, whose n

  • I actually thought about starting an online service to do just that, but I decided my security skills weren't up to par with the level of attack that *might* come about. I mean, the business plan is to collect a pittance a month from a few thousand tin-foil-hatters, but the reality is that if a service is designed well enough to attract the tin foils, then one day it'll probably actually attract someone with a real and determined enemy.

    Ignoring for the moment any issues of inability to push the button, how
  • What if... (Score:5, Funny)

    by jones_supa ( 887896 ) on Wednesday January 10, 2007 @04:34AM (#17536360)
    What if after your death your relatives just walk in and happily unplug your Linux boxes (having no idea how they even work) before your cool scripts even get a chance to run. :S
  • Snow Crash (Score:4, Funny)

    by locokamil ( 850008 ) on Wednesday January 10, 2007 @05:05AM (#17536518) Homepage
    Took my cue from Snow Crash and got my dead man's switch wired to a W80 warhead.
  • Internet dating (Score:5, Interesting)

    by Anonymous Coward on Wednesday January 10, 2007 @05:20AM (#17536586)
    Ok it sounds paranoid but on several occasions I've met up with someone from the internet.

    I usually have a few details about them but given I'm into the alternative scene (and I don't mean music) you don't usually just pass these details to a friend.

    Never the less, meeting up with someone like this for these kind of activities is down right dangerous, taking a few precautions is always sensible.

    I usually put together a zip file filled with every piece of contact information I have for this person and use a cron job to email this in 48 hours if I dont stop it.

    I also send a text message to myself prior to entering anyones house that I am meeting like this - the uk mobile phone companies will store location information for up to 3 years.

    Ok its paranoid but I know several people (though usually women) that have been raped meeting like this - worse things could possibly happen as you are taking your life in your hands doing though. I'll admit that being a guy I am probably less vulnrable - but its better to be on the safe side and atleast give yourself some backup.

    Its never gone off before... but its nice to know its set up - just in case.
  • Resurrects the person who uses it.
  • I've got one. (Score:5, Insightful)

    by munpfazy ( 694689 ) on Wednesday January 10, 2007 @06:20AM (#17536932)
    I often take part in political protests, and have on occasion been arrested and held for days.

    So, I put together a quick routine using perl and chron that dispatches email to my workplace, the local legal rep contact, and some friends. The later includes directions to a hidden key and asks them to feed my cat until they hear from me. I only enable the system when I'm expecting a significant risk of arrest. Once it's started, if I don't either log into the machine or send myself an email containing a specific string once every 24 hours, the alarm goes off.

    Turns out it's never actually been used (except when testing.) I did get caught up in a surprise arrest not too long ago, but since my girlfriend was going to be at home and able to take care of any problems I didn't turn on the system.

    But, if you ask me, trusting life-changing information to a php script is a really, really scary idea. Even my trivial "please feed my cat" letters included disclaimers explaining that they may have been falsely triggered.

    Now, on the other hand, the possibility of spoofing dead man's letters from other people *does* sound promising.
  • by linvir ( 970218 ) * on Wednesday January 10, 2007 @07:15AM (#17537214)

    Good day for this story. somethingawful [] has a great article about this today. Quoth the website:

    Section Two: Arranging my Funeral
    When my body is prepared to my satisfaction, gather my people around it to weep and mourn and say their farewells. In the unlikely event that by the time of my death I have not become the leader of a people, please find those who love me best.

    Go and read it.

  • This seems a little foolish to me. If you're anything like me you'll forget to check in one day, maybe when you go on holiday. What kind of failsafes have you built in? Does it attempt to contact you in a variety of ways before assuming you're dead? Leaving it to an overly logical machine seems dangerous - there are several things which could well happen:

    1) It fails to recognise your bucket-kicking and doesn't send out any of the vitally important information, so none of your friends get the passwords (or
  • At work we have processes so that if I fall under a bus or whatever, people can get hold of the passwords etc. The processes are all properly documented so the only hassle they'll have is a bit of short term cover whilst they recruit a replacement.
    As for family & friends, I guess they'll find out the same way people always have and as for special messages, if it's that important they already know and if it's not, why hassle them when they've got more important things to do like get me boxed and shipped
  • by David Horn ( 772985 ) <> on Wednesday January 10, 2007 @09:27AM (#17538120) Homepage
    Might I suggest a button that you have to push once every 108 minutes? You could even link it to a computer and enter a sequence of numbers in to reset the timer...
  • This is true... (Score:5, Interesting)

    by Anonymous Coward on Wednesday January 10, 2007 @09:51AM (#17538434)
    About six years ago I had the misfortune of working for a company where our lead developer was a complete fruitcake. He wore all black every day, put his cigarettes out on his keyboard, you name it. He was one of those die-hard, born-in-the-soup hackers who started out configuring the household appliances to kill his family.

    A genuine genius, and impossible to work with.

    Well, one week he had happened to catch some variant on the face-melting death. I'm talking about the kind of influenza which turns your various facial orifices into creeping faucets of mucus. His wife assured me of a fever which would kill a lesser being. Sweat sheeted off his face like a rainstorm on a greenhouse roof. Needless to say he took some time off.

    I get a call on Friday afternoon and it's him. The sounds coming from his end of the call were like the elephant throwing up and trying to talk into the little voice scrambling doohickey from the movie Scream. "You have to come get me," he says. "Why?" I reply. "Because I'm in no shape to drive, and I need to login to my computer there." Empathetically, I told him to stay there if he was sick. "You don't understand," he barfed, "If I don't login once a week..."

    Yes. He had a DMS on our key development machines. One which he explained would lock up everything tighter than [gratuitous image deleted].

    I was unthrilled to say the least, and refrained from chewing him out as he brought his barely clothed mass of plague into my beautiful car, coughed plumes of virii and bacteria into our office, made my boss practically bust a vein in his forehead as I led his nearly-blind ass to his computer-- all because he refused to share his password with us to access and protect company property --then finally have the nerve to croak a child-like plea for McDonald's from my back seat on the way home.

    Once he was fully recovered we had the intervention and asked the usual questions, Why do you think this is necessary? What are you hiding from us? How screwed would we actually be if he actually died? Etc. In his paranoid, seen-the-Matrix-too-many-times universe, there was nothing wrong with installing some 'basic security'.

    I did mention this guy was a genius, right?

    The boss caved completely, and to be honest, we all knew there was no way in heck we could find whatever weird little bombs he'd hidden in our own system let alone the machine he'd practically joined to at the spine 12 hours a day. I quit the company that June, Mr. Maniac is still writing all their code and the company is quite successful.

    So, yeah, DMS... Why send email to the unworthy after you're claimed in the Lord's rapture, when you can just grab your entire company by the nuts and twist?

    (Posted as AC because I'm at work.)
  • by guruevi ( 827432 ) <`moc.stiucricve' `ta' `ive'> on Wednesday January 10, 2007 @01:09PM (#17541638) Homepage
    Whenever I'm close to computers and electronics, everything works smoothly. If I leave for more than a few days, the whole environment starts coming down, and it's not something I programmed, just something that happens.

    My first job, I got fired, the next week the whole AD environment went down for hours on end
    My second job, I quit, the next week, all firewalls went into some type of crash, the network was overloaded by a broadcast-zombie and there was some type of virus
    I left home, went living somewhere else, the computer of my dad smoked, he had to buy a new one
    Another job, I was a freelancer, I left, next week I got bunches of nagios alerts
    Another job, I was a sysadmin, I got laid off, next week, nobody could receive e-mail and some type of update made it that networking got in trouble
    Last job, I was a sysadmin, I got fired, yesterday somebody told me that the whole network was down (>30000 nodes)
  • My DMS (Score:3, Funny)

    by Kazymyr ( 190114 ) on Wednesday January 10, 2007 @02:04PM (#17542784) Journal
    ...will encrypt all my personal data with quadruple-ROT13. That'll show'em!
  • by rdmiller3 ( 29465 ) on Wednesday January 10, 2007 @03:41PM (#17544512) Journal

    I hadn't really thought about this until the question came up, but it sounded like a fun mental challenge so I came up with a few ideas for improving the concept:

    Multiple Activation Stages
    The first thing that came to my mind was a DMS to warn you that your main DMS will be triggered soon if you don't "check in". A second stage would send a similar warning to a few other people, encouraging them to find you and to personally warn you about the DMS themselves. You might want to disguise that one as a "request for critical maintenance" from a system which sounds important.
    Secure Check-In Protocol
    Have your DMS send you a unique check-in ID which you must use in your response. Or if a first-stage DMS has already been triggered, require a special password for deactivation of the continuing DMS sequence.
    Multiple Triggers
    More than one trigger input, in combination and/or in sequence, to more robustly define the conditions for activation. For example, if you haven't checked in recently AND several check-in reminder messages have bounced.

    Ultimately though, if it's something important then I think a human being should be part of the process. A person would be a good sanity check. Nobody writes bug-free software, and I'm guessing that it could be pretty difficult to test a complicated DMS.

As of next Tuesday, C will be flushed in favor of COBOL. Please update your programs.