What's up with IT, Doc? Rabbit hole reveals cause of outage
- Reference: 1676017927
- News link: https://www.theregister.co.uk/2023/02/10/on_call/
- Source link:
This week's love letter to being on-call comes from a reader we'll [1]again Regomize as "Andrew" whose phone rang unreasonably early: 06:00 in the blessed AM – on a Sunday no less.
"A client called in a panic as he had no power to his home office equipment. The switch in the distribution box would not reset, so could I come and see what was causing this issue."
[2]
Andrew agreed to come out and have a look.
[3]
[4]
"Nobody but me is daft enough to go out on call at silly o'clock on a Sunday morning," he admitted.
But go out he did. With his box full of tools that he believes can fix any IT issue.
[5]
Andrew started with the most potent diagnostic technique of them all: turning it off and turning it on again.
Doing so a few times showed that the client's fridge was the cause of the outage.
So Andrew tugged and lugged the machine until he could see its power cord … which showed the unmistakable signs of having been nibbled, bitten, chewed, and otherwise damaged by dentition.
[6]No, you cannot safely run a network operations center from a corridor
[7]User was told three times 'Do Not Reboot This PC' – then unplugged it anyway
[8]This can’t be a real bomb threat: You've called a modem, not a phone
[9]Don't lock the datacenter door, said the boss. The builders need access and what could possibly go wrong?
IT isn't Andrew’s only skill: he also has an electrician's ticket, so he rewired the fridge.
As he did so, he wondered why the severed cord – which carried 240V when whole – was not accompanied by a corpse given the likely conductivity of whatever beast had unleashed its chompers.
[10]
Andrew mused about this out loud, within earshot of his client. The client "became pale and looked upset, then quickly called his wife and asked if she had seen their pet rabbit."
She had not.
A swift search of the client's home ensued, thankfully producing a non-tragic ending.
"Said bunny was located in its box, with burnt off whiskers and a sore nose, but otherwise unharmed," Andrew recalled. The loving bond between human and rabbit was unbroken – if singed.
If something furry has chewed your tech, [11]click here to email your tale to On-Call and you might be our pet story in a future edition of this column. ®
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[1] https://www.theregister.com/2021/04/09/on_call/
[2] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_onprem/front&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=2&c=2Y@Yj0-glO2SXLhuhI@cVsAAAAE0&t=ct%3Dns%26unitnum%3D2%26raptor%3Dcondor%26pos%3Dtop%26test%3D0
[3] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_onprem/front&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44Y@Yj0-glO2SXLhuhI@cVsAAAAE0&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[4] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_onprem/front&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=3&c=33Y@Yj0-glO2SXLhuhI@cVsAAAAE0&t=ct%3Dns%26unitnum%3D3%26raptor%3Deagle%26pos%3Dmid%26test%3D0
[5] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_onprem/front&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44Y@Yj0-glO2SXLhuhI@cVsAAAAE0&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[6] https://www.theregister.com/2023/02/03/on_call/
[7] https://www.theregister.com/2023/01/27/on_call/
[8] https://www.theregister.com/2023/01/13/on_call/
[9] https://www.theregister.com/2022/12/23/on_call/
[10] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_onprem/front&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=3&c=33Y@Yj0-glO2SXLhuhI@cVsAAAAE0&t=ct%3Dns%26unitnum%3D3%26raptor%3Deagle%26pos%3Dmid%26test%3D0
[11] mailto:oncall@theregiste.rcom
[12] https://whitepapers.theregister.com/
Re: Ouch
Yup. That's one lucky bunny.
Name wouldn't be Roger, by any chance ?
Re: Ouch
cue FX of rabbit getting shocked, showing skellington inside etc etc etc.
Re: Ouch
I bet it was pretty amped afterwards...
Re: Ouch
Seen a pet rabbit take out EVERY cable behind a PC and survive.
Was called out to a "not working PC" in a house where someone was house sitting. They had let the pet rabbit run around the front room. Only later did they realise all the cables were shot. Monitor, printer, power, internet... This one was lucky as it had not quite gone through the mains lead yet.
Re: Ouch
Being shot by 220 V right in the teeth is certainly anything I'd wish inflected onto anyone
Certainly not to a rabbit. Honestly though, I can think of one or two people to whom I would not wish this happening but if it did, I wouldn't feel terribly bad or sorry.
Re: Ouch
Despite their best efforts to prevent repeat nibblings, I think a former neighbour's rabbit made it to 4 or 5 nibblings with current flow before it expired.
Re: Ouch
Ouch, I mean, that stings quite a bit on the old fingers already....
We have one of the local cats visiting our garden quite frequently. It is an extremely friendly cat. We have plastic chairs there, which unfortunately means nasty electrostatic charges accumulate as you sit. Said very friendly cat came to say hi, smell the hand, cuddle a bit. She came to step two, and got a shock right on the nose. Poor little thing! (she got over it).
Re: Ouch
This actually happened to me, my housemate's rabbit chewed through the iron's cable the day before I had a job interview. I can't remember if it was live or not at the time (the wire, not the rabbit)
How happy I was -->
Alice, is that you?
So glad I did not have to go through that rabbit hole...
Depending on the type of cable coupled with how poor bunny nibbled at it, it's possible he just nicked the earth (ground for our leftpondians) and nearly through the line.
That would give enough leakage to trip an RCD/RCBO.
Squirrels and rats tend to be the reason I end up crawling under decking. I don't find as many fried bodies as you would imagine.
I think it's one campus at Alabama State University that's nick named Squirrel U due to the amount of incidents.
Learned that from 'The Internet Tour Bus" back 25 years or so ago!
I had some 240V Christmas lights in the garden one year. A fox chewed on the cable and, oddly, the RCD did not trip but the 3A fuse did blow and there was a reasonable amount of burning of the plastic around the bite zone.
So I guess it got lucky and crushed the conductors together without touching them directly, maybe? Although presumably the spark/flash in its mouth would have been startling.
On the other hand, I don't actually know what "tripping an RCD by touching the live wire" would feel like as I've never had that happen. Does anyone know?
(For the record, I do know what "touching a live wire before the days of RCDs" feels like! Oddly, I would say that it was not as bad as the "dishwasher motor capacitor discharge via the mains plug" shock I once got before that got banned! )
Does anyone know?
It's slightly unpleasant. In one case in my distant youth it left me oddly confused and took about ten minutes to fully recover (maybe I also hit my head as a result of the shock, which may have contributed). The RCDs did their job though: I'm still fully alive after tripping such breakers trice with my own body parts.
I'd say it's more than slightly unpleasant.
Definitely not on the old "Let's do that again!" listie ...
The capacitor is going to dump anything it's got in one go.
The RCD/RCBO is going to bang out immediately. BS7671 says a maximum of 40ms to trip. In the real world from testing I'd guess median is around 20ms. The longest I've found without me failing it is around 30ms. Fault current maximum is 30 mA.
I've only gone through a live cable once and the damage to my cutters was quite spectacular. Normal reason for tripping is producing a L-E fault/short when cutting a dead cable..
My late* father tried to fit a hook to a wall and in the process managed to drill into a 3 phase 380V 25A cable once, with the drill progressing fast enough to connect the steel mantle he'd just penetrated to all 3 phases at once. And this was in the time before RCDs.
As it was inside a wall he was saved from the resulting instant vapourisation of about 1cm of the drill tip but the flash and bang were considerable before the main circuit breakers decided nobody could possible want that much power in our house :).
I had to chisel open the freshly tiled wall and make a hole large enough to repair the cable and waterproof it, and then we had to redo that wall.
Thankfully we had enough spare tiles, and a spare drill..
* No, he still managed to simply pass away of old age - he bought a metal detector soon after this adventure :)
Chewed wires?
Try this one: [1]https://www.pestend.co.uk/2019/05/07/squirrels-can-cause-serious-risk/
Now that really is a serious case of the munchies! No word of anything actually getting flambéed though.
[1] https://www.pestend.co.uk/2019/05/07/squirrels-can-cause-serious-risk/
I got a call from my ex-wife one night panisking because all her power had gone off. I drove over and started troubleshooting. About an hour's testing, unplugging appliances and resetting the circuit breaker suggested that the problem was in the kitchen. It turned out that one of her cats (un-neutered male) had a habit of sleeping on top of the fridge. This time he had decided to spray his corner and the urine ran down the wall and seeped into the socket the fridge was plugged in to! I had to remove the socket, rinse it out and dry it carefully before reinstalling it. I also sealed the edges of the socket with silicone. I also arranged an appontment for the cat at the vet's - the unkindest cut of all!
Why did you arrange an appointment for your ex-wife's cat? An enquiring mind needs to know.
Upvote for sealing the socket!
Absolutely!
Top man for thinking of that.
Re: un-neutered male
Once a tom cat has learnt to spray things he'll generally never stop even after surgery. It's best to get 'em young.
Re: un-neutered male
"It's best to get 'em young" or else there's still this [1]solution . Trust me, your guests will not notice the difference.
[1] https://www.theenglishkitchen.co/2009/07/rabbit-pie.html
So a disconnected fridge becomes a disconnected cat.
Now we know ..
.. how they came up with the Energiser Bunny..
D*mned Wabbit
Happened to me quite a while ago
Mid game on a ZX spectrum on the family TV (with the speccy on the floor in front)
Sisters pet rabbit lopes past, sniffs the (low voltage) cable near the back of the computer, and then snips through it and buggers off.
It looked like some reflex to do with clearing roots - it tried to toss the wire away before leaving.
I did get to add an on-off switch at the cut -something which the ZX range was missing.
I remember chatting to some retired GCHQ types, who had found it hilarious that a US listening post in the UK (presumably Menwith Hill) had had massive problems with disconnections.
Apparently they'd not heeded their British colleagues warnings about protecting the cables from the British bunnies who were happily chewing through the unprotected cables.
I once did a consulting job at a government department which shall remain unnamed but whose staff were not exactly fast (that ought to leave it vague enough :) ) - frankly, the lack of activity was driving me nuts. I don't mind not being rushed off my feet, but these people would have been outrun by a snail on a salt lick.
To alleviate boredom, I started counting rabbits at the end of the day when walking from the main building to the gate, and I generally managed to get to 40 or so. They all were grey-ish - a bit like the people working in the building, but moving faster (you may sense a theme here - it was frustrating).
A few months in (I think it was spring heading for summer with quite a lot of nice sunny days), a colourful rabbit showed up amongst them - white with brown patches, demonstrating that the fence was not exactly a barrier for them. And rabbits being rabbits, the population soon expanded with the cause clearly visible as more non-grey rabbits started appearing.
When I left, my last walk-to-the-gate count was over 60 :)
Two four you
Had to investigate the in-laws fridge a few years sinceupon. It was in an enclosed rear porch and had suddenly ceased working.
Nothing untoward with supply, plugs, fuses and cables so I went deeper.
Top off and small PCB exposed with the remains of a fried slug across trackwork, holes in copper and PCB.
It was beyond rebuilding and doo obsolete for spares unfortunately so a replacement secondhand fridge sourced.
I look a month holiday to visit family, flying out of Heathrow. Rather than paying for parking I parked at a relative's close to the airport and went in by local cab.
A week or two after getting back the car got poorly so cue a trip to the garage and left the car there.
The problem was actually a failed rear ABS sensor (Passats do that sometimes) but I did get a call asking if I had a mouse problem.
It appears that in our months absence the little blighters had climbed under the bonnet and built a sizeable nest under the plastic engine cover, making a chewed mess of some wiring.
Little sodlets
Ouch
""Said bunny was located in its box, with burnt off whiskers and a sore nose, but otherwise unharmed,""
Wow, just WOW ! I bet said rabbit had never ever since approached any type of wire by less than 10 m ever since !!!
Being shot by 220 V right in the teeth is certainly anything I'd wish inflected onto anyone ! Gaah.