Sysadmin cured a medical mystery by shifting a single cable
- Reference: 1755243014
- News link: https://www.theregister.co.uk/2025/08/15/on_call/
- Source link:
This week, meet a reader we’ll Regomize as “Jake” who told us of the time he worked as the sole sysadmin for an entire hospital.
Jake’s job focused on classic information technology, but in the story that he sent to On Call medicos summoned him to investigate a malfunctioning CT scanner. Such machines connect to large and powerful workstations on which clinical staff view images captured by the scanners.
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He poked about on the workstation and was surprised to find it crawled along, scarcely able to display images within a reasonable time.
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“I am not in any way trained on medical machinery,” Jake told on Call, so he started by applying his IT eye and found a CAT-5 cable snaking away from the scanner and into a wall connector, from which a similar cable connected to the large and powerful workstation.
Jake knew those cables were not of the type used elsewhere on the hospital network, so he surmised the scanner and workstation connected over a dedicated network, and that something about it was the reason for the problem.
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As such, he started tracing the cable and found it led to the hospital basement, and from there into a cable gutter that ran to the one patch room in the ten story building. The cable from the CT scanner slotted into a port on a patch panel, which used a patching cord to reach another patch panel. Next came another very long cable from the patching room, to the basement, all the way back to the room housing the CT scanner, and then into the workstation.
“I realized the CT scanner and the workstation were three meters apart but connected over 250 meters of cable that bounced through four connectors,” Jake told On Call.
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He therefore unplugged the cables that linked the scanner and workstation to the wall socket and connected them directly instead.
Doing so reduced the length of cable connecting the two machines by approximately 245 meters, after which the workstation “problem” disappeared.
Jake didn’t tell anyone about his fix. He just basked as hospital staff “applauded me as a real wizard.”
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Have you fixed a silly network config? If so, connect with On Call to share your story by [10]clicking here to send us an email . We’d love to link you with your fellow readers on a future Friday. ®
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[5] https://www.theregister.com/2025/08/08/on_call/
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So it was a Cat-5 scanner
++?????++ Out of Cheese CAT Error. Redo From Start.
More than once
Network switches running on config in memory that had never been saved or even backed up, the first power outage and the whole network was broken with ports inundated by broadcast storm traffic, DMZ switches were directly connected to production network and so was the open internet.
A network at a cult (yes, a real live Christian fundamentalist cult which, I have been told, still practices gay conversion therapy despite it being illegal) which had almost as many switches as PCs in a sprawling Victorian building in Cumbria where all the cabling ran through the suspiciously well secured cellars (big, strong and obviously regularly used metal doors with conspicuously heavy duty padlocks) to which I was refused entry.
The dairy where they'd lost connection to the warehouse from the server/Comms room because they'd demolished a building in the yard, said building had contained some of their fibre patch panels.and yes, the fibre from the warehouse passed through it.
The hospital which still had live 16MbpS token ring bridged to ethernet and back again because management had authorised the expense and refused to accept "the lost investment" nearly 20 years later...
And there are so many more, like the architects who took wire cutters to the WiFi antennas on their broadband router because they were scared of being hacked and losing the contents of their two PCs to "competition"
“applauded me as a real wizard.”
Which he obviously was.
Jake has spoiled the ability of whoever is in the basement to packet sniff and spy on all that sexy CT imaging.
Network plans
>Jake didn’t tell anyone about his fix.<
I wonder if the problems with the CT scanner started when someone got rid of a tripping hazard and decided to replace the direct cable connection across the room by properly connecting the CT scanner and the workstation to the existing wall connectors without telling anyone.