Linux admin asked savvy scientist for IT help and the boffin blew it
- Reference: 1729495446
- News link: https://www.theregister.co.uk/2024/10/21/who_me/
- Source link:
This week's main character we'll Regomize as "Igor" because he used to work in a lab back in the day. The lab was full of networked computers, but none of the boffins – for Igor was a boffin – knew much of how the software side of it all worked.
What Igor did know how to do was put together the custom cables and RJ45 connectors that linked it all up. Thus it came to be that when one of the network admins needed a hand adding some new Linux boxes to the network, Igor was recruited to handle the physical stuff while the admin worked magic at the keyboard.
[1]
Mostly this involved removing cases, inserting network cards, restoring cases and then attaching all the appropriate cables into the right ports on the machines. However, this was in the days before network cards automagically configured and diagnosed themselves, so the network guy asked Igor to rig up a loopback cable for that purpose.
[2]
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Such cables connect to the transmitting and receiving ports on the card and ensures that it can, at least, talk to itself. It's a little more complicated than that but this is Who, Me? - not a networking tutorial.
When Igor's loopback cable was plugged in to a working card the little green activity light would spring to life, providing reassuring warm fuzzies all round. Such a handy thing to have.
[4]
Before very long, the new machines were all networked and the lab was screaming along at ten spectacular megabits per second, which was considered quite speedy in those days.
[5]Compression? What's that? And why is the network congested and the PCs frozen?
[6]After we fix that, how about we also accidentally break something important?
[7]Personalized pop-up was funny for about a second, until it felt like stalking
[8]Did you hear the one about the help desk chap who abused privileges to prank his mate?
The next day Igor returned to the lab and his usual boffinry duties, but found the network not nearly so speedy as he would have liked. Indeed no-one in the lab was able to boffin as quickly as they would have liked, and the network admin's demeanor had turned sour as he muttered strange phrases like "packet loss" and "failed pings" and "collisions".
When Igor went to join them at the hardware cabinet, he was shocked at what he saw: orange and red lights had almost completely replaced the lovely green he saw the previous day.
Just them he had a thought. "Could this have anything to do with my loopback cable," he asked?
"What do you mean?"
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"Well," he said, "I found it so handy yesterday that I didn't want to lose it, and I thought one of the unused ports in here would be as good a place as any to keep it …"
With that he reached in and unplugged the cable, at which point all the red and orange lights immediately turned green and joyous sounds were heard throughout the lab.
Well, almost throughout the lab. The admin had some choice words for Igor about not plugging anything into the network cabinet if you don't know what you're doing. And Igor learned that what can be a powerful tool when you know what you're doing can be very dangerous when you don't.
Have you ever discovered that you know just enough about something to do some damage? [10]Tell us about it in an email to Who, Me? and we might share your knowledge with other readers and brighten some future Monday. ®
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Configuring network cards was painful in those days, one mistake and you could interrupt the entire network...
And as we all know, networking mistakes cost a packet...
Regomiser
Wouldn't Jack be a better name for someone involved in old-school networking?
Or even cabling in general...
Token ring was a shining example of how not to make cabling user friendly. I'd ask what was the alternatives of the day were, though ethernet pre-dates token ring by several years.
And the IBM cards weren't exactly cheap.
The problem with Token Ring was if you unplugged the wrong cable at the wrong time, the token fell on the floor and was almost impossible to find. A replacement token from IBM was very expensive.
I have fond memories of our BOFH sending new PFYs to hunt for the token to teach them life isn't fair.
That's why it's best to use a Tolkien ring.
Well there was cheapernet (10BASE2) which involved the horrors of coaxial network cabling where because it was all in one line, with the required terminators on each end, interruption anywhere tended to take out the entire network. For larger networks there was the further horror, and vast expense, of aggregator boxes which combined multiple such lines. Naturally the maximum speed was 10mb, and that was on a good day when nobody else was using the network.
A bad connection on 10base2 could result in a reflection and signal loss in the middle of an otherwise working run which could drift backwards and forwards by one machine over a day! First time I saw that it did my head in - how could a single cable that worked at both ends not work for 20feet in the middle? TDR=£1squillion so finding the bad connection meant literally checking every T-piece and connector on the line beyond the fault. Part thick/part thin ethernet feeding three floors and running through crawl spaces and ducts inside and out so it was bound to be damp ingress somewhere ... or the joiner someone put under a secretary's desk because they had cut the coax too short ...
In a previous role I'd been moved on from being IS Manager to working on a global ERP implementation, leaving local systems in the charge of my operator (who was ex-finance and had only a few years IT knowledge*).
A while later they decided to replace the thinnet (10base2) networking with Cat-5, an easy enough job except that this was in the days before autosensing on router ports (for the youngsters, you had to use a crossover cable when connecting routers and switches together - the cable pouch in my laptop bag still has one). The installers hadn't explained this, and had left a mix of unlabelled patch cables behind so when my former assistant did some repatching most of the network went down and she couldn't work out the solution or even undo her changes.
I was asked for help and quickly sorted it, then explained the problem and got the cable tester out to label all the patch cables. A couple of days later senior management told me, in no uncertain terms, that I shouldn't have got involved, it wasn't by role, etc. I did ask whether I should have ignored the problem and left most of the business unable to work but didn't get a response! I already knew my days were numbered and was only hanging on for the redundancy payout which came a few weeks later - as I expected the whole place was largely closed within a couple of years.
*One of the senior managers once instructed me to, "Make sure xxxx knows everything you know!" My suggestion that she would have to go to University then gain at least 10 years experience first didn't go down well.
Rollover
(for the youngsters, you had to use a crossover cable when connecting routers and switches together - the cable pouch in my laptop bag still has one)
earlier this year, while diagnosing an issue, i was asked if a rj45-rj45 roll over cable was needed. I didn't think the guy asking was old enough to know what one of those was!!
A while later they decided to replace the thinnet (10base2) networking with Cat-5, an easy enough job
An easy enough job in one room, or perhaps one small floor of a building. But an entire building, replacing a single cable run with an individual one to each device could be a major undertaking involving diamond drills, cable ducts, auxiliary cabinets, switch banks and patch panels in racks, cable trays and more.
But an entire building,
I worked in a ~ 50s or 60s built 10 floor building with a stairwell with a window alcove running the full height to let in some daylight. Then when they recabled at one point (maybe about 15 years ago?) they repurposed the whole ground to top window alcove as a giant cable run. No more natural light for us when climbing stairs! (but, it has to be said, a better network speed & capacity).
Re: But an entire building,
Surely a better, faster network always has to be more important than access to natural light?
the whole place was largely closed within a couple of years
Yup. That's what happens when you have morons at the top who think their title is more important than your expertise.
They know nothing about what you do or why, but damn can they order you around.
Yeth marthter!
Igor + loop-back instantly reminded me of the motto:
"What goeth around, cometh around"
Doffs hat to the late, great sir Terry Pratchett
I'll get me coat. The one with "Carpe Jugulum" in the pocket.