back to article Feline firewall woke developer to declaw DDoS disaster

A developer named Danny Guo has shared a story of the time his cat alerted him to a DDoS attack. In a post on his personal site, Guo revealed that he once worked at a startup that was yet to develop a formal on-call rotation. He also revealed that his cat would occasionally groom his hair. "She did it occasionally, and I …

  1. John Robson Silver badge

    But pager duty has great tones

    "The server's on fire...."

    "It's your fault, it's your fault, are you gonna fix it, are you gonna fix it...."

    1. jmch Silver badge
      Trollface

      Re: But pager duty has great tones

      Or...

      "The server, the server, the server's on fire..... The server, the server, the server's on fire..... I'm not on call duty, let the m..f..r burn!!"

  2. Inventor of the Marmite Laser Silver badge

    I felt a disturbance in the Force, as if thousands of souls cried out in terror.

  3. Martin Summers

    It was obviously feline a disturbance in the force.

    1. Korev Silver badge
      Coat

      Fur sure...

      1. The Oncoming Scorn Silver badge
        Coat

        Was there a out of hours claws in his contract of employment?

  4. John Miles
    Joke

    Cat's mind

    Magic box that slave seems to think of even above me has made a noise, probably set to remind him to feed me and he's missed it - try waking him gently so he remembers to feed me.

    Alternative - drat magic box woke him from my mind control experiments, though I'm losing faith there is a mind to control.

  5. Bebu Silver badge
    Windows

    Vardøgr

    《"You might guess that the AWS alert caused my phone to vibrate or make a sound, waking my cat up first," he wrote.

    If that's your guess, you're wrong. Guo keeps his phone in do not disturb mode during the night.》

    Years ago when used to have a FM radio/wireless on my desk and cell phone next to it, I noticed that a good 10 to 15 seconds before the phone actually rang (same for sms/text) the radio would experience a distinct sort of background static or interference (even if it was on silent or vibrate.) Same static could be heard on the POTS landline if I was using it at the time.

    I never could work out what was actually happening there. Was pre 4G so possiblly 3G or GSM/2G and I also subsequently upgraded to a DAB+ digital radio which never exhibited this effect.

    More than once I have had some bemused users in my office when I have reached for the phone well before it rang. :)

    A BOFH with apparent omniscience inspires best behaviour all round. :)

    So I wonder if the cat heard this vardøgr signal from some high (audio) frequency from the phone or from a nearby clock radio etc. I also notice the screen normally activates even when on silent. Of course moggies are evil buggers on their own account at the best of times...

    1. heyrick Silver badge

      Re: Vardøgr

      "when I have reached for the phone well before it rang. :)"

      That's the old GSM/GPRS signal interfering with things. Like "duuuh duh-duh duh-duh duh-duh duuuuh", yes?

      I've done the same thing, by hearing that and knowing somebody was in the process of trying to call me.

      I think you were hearing this on older phones because 2G uses amplitude modulation for low bandwidth data, like text messages and "are you there?" requests, and that coupled with the frequencies in use would induce interference in unshielded cabling (like to speakers); but this is a dim and distant memory so take with a heft of salt.

      1. Arthur the cat Silver badge

        Re: Vardøgr

        "when I have reached for the phone well before it rang. :)"

        That's the old GSM/GPRS signal interfering with things. Like "duuuh duh-duh duh-duh duh-duh duuuuh", yes?

        BT,DT. I also used to use a Psion 3 as an alarm clock, and that would make the radio sound like an arcade game laser firing as the Psion woke up for the alarm.

        1. My other car WAS an IAV Stryker

          Re: Vardøgr

          That noise... from the conference room Polycom phones circa 2005-2007 during teleconferences (especially when calling into WebEx) when I first started my "career" job back at Styker/Abrams HQ. Everyone was told to turn their cell phones OFF -- not just "silent" -- for meetings. (As cell phones evolved and old models were retired, it got better. The older Polycoms were eventually replaced also.)

      2. John Brown (no body) Silver badge

        Re: Vardøgr

        "I've done the same thing, by hearing that and knowing somebody was in the process of trying to call me."

        My old Nokia used to do that if I had the radio on in the car. Whether the change is in the car audio system or the phone, it doesn't do it now with a much newer car and totally different 5G smart phone. On the other hand, KDEConnect pops up a notification of SMS/Teams/Outlook/Incoming call on my laptop screen a few seconds before the phone deigns to inform me by beeping or ringing

    2. I could be a dog really Bronze badge

      Re: Vardøgr

      Yes, when digital mobile came along, the signals caused a lot of interference on inadequately screened electronics - like pretty well anything not built to "if you have to ask, you can't afford it" standards.

      You could hear this as an occasional chirp as the phone and network would check in to keep the connection up to date. But as described, once a call is being made, there's an exchange of information between network and phone before the phone alerts the user to the call - and this mass of data causes the described interference.

    3. John Miles

      Re: Vardøgr

      What you were hearing from FM radio was the pulses of signal the phone uses for talking to the tower, these will be picked up by the audio circuits and amplified - giving the noise you expect. Phone signal strength has reduced as technology improves and new radios are better designed to reject the noise

      Cat's hear frequencies well above humans - it is likely when screen switches on it will make noise the cat hears we don't or may just be the light flashing

      1. Spazturtle Silver badge

        Re: Vardøgr

        If you put your phone next to a microphone and then run something demanding on it the microphone will pick up the high pitched noise the CPU makes at higher clock speeds. Cat might have heard the noise from the phone clocking up when it received the push notification.

      2. Doctor Syntax Silver badge

        Re: Vardøgr

        Yes. It also seems to have a natter with the base station(s) when moving from one to another. With an older phone it would break through on the car radio. Presumably before receiving an SMS it's confirming that it's still on and listening.

    4. GlenP Silver badge

      Re: Vardøgr

      In my occasional forays into managing presentations and talks there was always one absolute rule - turn phones off in the vicinity of audio equipment, especially if they're Nokias! I don't now if Nokia were worse than others or were just fairly ubiquitous at the time but the sound was distinctive. I can well believe a feline would pick up signals from a mobile even in DnD mode.

      On the other hand I once woke up because a monitoring email did not come through! There are a couple of system email overnight from processing systems and on one occasion the batch process failed so the email wasn't sent. I woke up at around 2am and was able to sort the problem before anyone noticed.

    5. katrinab Silver badge
      Windows

      Re: Vardøgr

      I had that with my speakers back in the 2G era. That was with a phone that had 3 AA batteries and made phone calls.

  6. Blackjack Silver badge

    [If that's your guess, you're wrong. Guo keeps his phone in do not disturb mode during the night]

    Unless he actually went and specifically blocked whatever App handles messages and phone calls, it may have made noise anyway, source, that's what happens to me in Android. Is amazing how many Apps just bypass do not disturb mode.

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