back to article CompSci teacher sets lab task: Accidentally breaking the university

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  1. tip pc Silver badge
    Big Brother

    walked to the lab to disconnet the switch?

    why didn't the techies just remotely disconnect the uplink port from the router?

    Surely the switches management interfaces where on a different vlan?

    Surely the university used ip helpers on the vlans configs?

    Surely the techies didn't use dhcp for the switch IP's

    surely the techies could have setup a static IP on their machines if they also fell foul of the malicious dhcp server.

    i guess these where in the times when these things where not well understood or implemented.

    Still impressive the techies knew exactly what room the malicious system was in and could go directly to it.

    Maybe the disconnect was a show of annoyance after they rectified the issue remotely.

    1. Pete 2 Silver badge

      Re: walked to the lab to disconnet the switch?

      > why didn't the techies just remotely disconnect the uplink port from the router?

      Maybe every previous year they did that. But this time there was a different techie (a techy techie?) who had had enough and finally wanted to make a point

    2. An_Old_Dog Silver badge
      Windows

      Re: walked to the lab to disconnet the switch?

      Maybe the switch was old enough -- TFA didn't give any dates -- that it didn't have the necessary features to practically allow remote administration.

      Back in the late 1990s I saw at my workplace removed-from-service 3Com switches whose "remote" admin connection was an RS-232C port on the back. The cable-length limits of RS-232C wouldn't allow a remote admin box at the other end of our building, let alone across campus!

      1. jake Silver badge

        Re: walked to the lab to disconnet the switch?

        It's called out of band signaling. Good for security, when connected properly.

        We used 'em with A-J dial-back modems.

        1. An_Old_Dog Silver badge

          Modem DoS

          Also in the late 1990s, I supported a database server running Intersystems Caché - an implementation of MUMPS. The departmental director had a single, analog phone line, which she shared between her desk phone and her modem-equipped PC, running PCAnywhere. This allowed her to dial in from her home PC, or from her laptop, and access her desktop PC, and hence, the DB server.

          Sometimes, she would forget to switch this off, so that when I called her during business hours, the modem would answer, and I'd get an earful of modem handshake tones instead of her, or her answering machine.

          One day this happened, and in frustration I used my voice to send fake (inaccurate) modem tones and nonsense syllables through my phone mouthpiece to her modem. It went silent. "Hmmm." On a hunch, I hung up and redialled ("Touch-Tone™"-ed) her number. The modem, in some sort of locked-up state, did not answer, and I got through to her answering machine. Hooray! A useful tactic, which I used from then on.

          She once commented that she sometimes found her setup locked up, and had to phone her secretary and have him power-cycle her modem.

          I don't know how this tactic would have worked, or not, with a answerback modem.

      2. collinsl Silver badge

        Re: walked to the lab to disconnet the switch?

        You can just plug them into a console switch - and then plug that into a physically separate management network. You can get 16/32 port ones which allow you to control a lot of devices in your network remotely which don't have their own remote management capabilities.

        1. tip pc Silver badge

          Re: walked to the lab to disconnet the switch?

          yep, systems like this have been about since it least the turn of the century and definitely before given that users used serial connections to conenct to mainframes with green screen terminals since the 70's

          https://www.raritan.com/products/kvm-serial/serial-console-servers

          https://www.lantronix.com/products/eds5000-series/

          not everyone had them but.......

      3. Peter Gathercole Silver badge

        Re: walked to the lab to disconnet the switch?

        Maybe the switch was new enough to report the MAC address of the systems plugged into it. They could have found the IP address of his 'rogue' DHCP server from any system that had obtained it's IP address from that server, and they then could have got the MAC address of that system, and queried the switch MAC address tables to work out which switch it was attached to.

        It is also possible that they could get information from the spanning-tree info for the network to work out which switch it was attached to.

        Or maybe they were diligent enough to have a map of all MAC addresses attached to the campus network, although that may have been a stretch.

        Personally, I probably would have set the DHCP server to white-list the MACs of systems you wanted it to control, and drop requests from any other systems.

    3. Anonymous Coward
      Anonymous Coward

      Re: walked to the lab to disconnet the switch?

      Why wasn't the demo DHCP server set up as a NAT router?

      1. Yes Me Silver badge

        Re: walked to the lab to disconnet the switch?

        > Why wasn't the demo DHCP server set up as a NAT router?

        Because that was planned for the following week's tutorial?

        Because the tutor was only one page ahead of the students?

    4. Anonymous Coward
      Anonymous Coward

      Re: walked to the lab to disconnet the switch?

      When Windows computers are not able to work as expected (I didn't say "work properly"), and you know you have Linux users somewhere on the network, you immediately know that it is because of nefarious activities by the aforementioned Linux users...

      So better to let them know how you are feeling by going to their location to do something that may have been done remotely.

      I am however surprised that no hammer was involved.

    5. chivo243 Silver badge

      Re: walked to the lab to disconnet the switch?

      Ha, this could have been me... And I did find just this situation happening back around 2000. And being a school, isn't teaching and learning what it's all about. I taught a lesson, and hopefully the teacher learned it. I even had a similar situation where a student had brought their own network cable from home, and unplugged a cable for the APs... and tried to use that. Bells and whistles that time! That surely required a visit! That's a paddlin!

    6. Randy Hudson

      Re: walked to the lab to disconnet the switch?

      "setup" is a noun. "set up" is a (prepositional) verb

    7. kmorwath

      Re: walked to the lab to disconnet the switch?

      The whole Uni in the same broadcast domain? It has to be a long time ago... I hope.

    8. Benegesserict Cumbersomberbatch Silver badge

      Re: walked to the lab to disconnet the switch?

      And don't call me Shirley.

    9. Steve Channell
      Pint

      Re: walked to the lab to disconnet the switch?

      the report "Don had inadvertently made his server the machine most likely to respond first. But as it was built to keep traffic in the lab" is a little too generous. DHCP uses (udp) broadcast messages, so there is no "most likely to respond". "was built to keep traffic in the lab" is also too generous - if there was a firewall policy to keep traffic in the lab Don's server wouldn't be a problem. What (likely) happened, was that campus PC's received a lab IP address complete with a lab gateway address that wasn't reachable.

      The route cause is likely that Don, kept UDP open to retain access to network printers.

      1. KarMann
        Headmaster

        Re: walked to the lab to disconnet the switch?

        The route cause....
        Pun intended? Or not?

      2. F Seiler

        Re: walked to the lab to disconnet the switch?

        i think most likely to respond should be read as, responded more quickly than the probably slowish uni servers.

  2. WhoAmI?
    FAIL

    I crashed one of two graphics domains

    When a mere spotty undergraduate in 1991, I was working on my final year project. The official title of the project was "The parallel computation of iterative fractals", but what it really was was "calculate the Mandelbrot set on Transputers". The Transputers were on a Meiko Computing Surface (MCS), and was the most powerful system the university owned.

    The MCS sat in a little room next to the main machine room, and its processors were split into several domains of various processor counts, and two of them contained a graphics board. We didn't always have direct access to it (researchers sometimes wanted to use it) so we had to use text or X terminals dotted around campus. These didn't have the means to output graphics from the MCS so I implemented a text output option which still ran on the graphical domain for the odd occasion I wanted to test.

    We were generally displaying graphical results in a 1280x1024 resolution, but this wasn't suitable for text so I normally lowered it to something like 50x50 when at a terminal. Note the word "normally" as this is important. One time, whilst sat at a DEC Station, I connected to the domain, wired up the processors, loaded my code, and hit "RUN". I should have taken the other meaning of "RUN" into consideration as a survival technique. I'd forgot to lower the resolution and was trying to output quite a lot of data to a terminal session which, oddly enough, did not have a terminal capable of displaying 1280 characters on a line. This also wasn't a gigabit network so it was going to take some time. I experienced a classic "Oh F***" second, hastily did the CTRL-C so beloved of failures, and hoped for the best.

    The program running didn't quit, but the link to the MCS did. I tried to re-connect to the domain but it thought it already had an active connection (which it did - mine - but was now dead). Unfortunately, the process on the graphics domain carried on churning out text data to a session no longer connected, and then sat there waiting to find out what I wanted to do. A quick chat with one of the MCS admins confirmed my fears - the domain was locked to my session and could not be stopped without rebooting the whole MCS. A reboot wasn't scheduled for a couple of days. I'd locked one of two graphics domains on the most powerful system the university owned through a simple absence of a comment marker.

    I got on with my project diary and kept my head down for a week.

    1. Sam not the Viking Silver badge

      Re: I crashed one of two graphics domains

      Inspired by James Gleick's 'Chaos', I wrote a little programme to draw the classic Mandelbrot Set. It ran on my home, pre-Windows, Amstrad. I had to let it run overnight to get a grainy picture plotted on the screen which I was then reluctant to stop and lose the image. Wanting a better, more detailed picture, I knew our work computers had more memory......

      Our server had a big (40 Mb!!) HDD which we used simply as file storage. In those days it was heavily under-utilised. I set the program to send its output to be stored there. Everything else on the system ground to a halt which although not uncommon, was unexpected and only I knew the probable culprit.....

      It was good friend Peter Norton who brought his Toolbox to resolve the chaos I caused. How we laughed......

      1. Michael H.F. Wilkinson Silver badge

        Re: I crashed one of two graphics domains

        Reminds me of the tiny little postscript file that could keep a laser-jet printer occupied for hours, and then output one beautiful, A4, 300 DPI, colour Mandelbrot image. This made use of the fact that postscript is Turing complete, so of course you can write a Mandelbrot program in it. And sure enough, someone did. To the delight of some, and chagrin of other, I might add. In part this was motivated by the fact that the printer had more memory and a faster processor (RISC, as I recall) than even a power PC back in the day. In part it was motivated by the "let's try it" attitude that has lead to many great things, many more wasted hours, and occasionally assorted disasters.

        There is also a postscript ray tracer, which has a similar effect.

    2. ben kendim

      Re: I crashed one of two graphics domains

      Lucky you, you had a terminal with a CRT...

      As an undergraduate in the 70's I decided I wanted to do image processing. The hardware available consisted of a Univac 1106, card punch machines, a line printer the size of a Volkswagen beetle (but significantly louder than that beetle sans muffler.) The software development environment was paper pads and marker pens (to draw diagonal lines across the top of card decks.)

      I chose 100 x 100 resolution (line printer was 132 characters wide) at 32 gray levels. As it was rather hard to find image data (where was Lenna when you needed her?) I wrote code to generate patterns including stripes and gradients to begin testing. (I remember one of them was based on the diamond shaped Renault emblem, easy to generate.)

      To output grey levels on the paper I used the FORTRAN-IV '1H+' Hollerinth at the beginning of each line, This caused a carriage return without linefeed. Then I sent multiple overlaid lines to the printer. At each character position a 0 level would be a blank, a 1 would be a period, and so on... I think level 31 was something like overlaid {M, W, E, 3, O, S, Z, \, /, [, ], +} or some such dark sequence. This meant each line was printed 12 times using that '1H+', before a line feed occurred.

      I submitted the deck of cards, and went away to lunch. When I came back, there was a note for me where the output printouts were placed. it said to immediately see the Professor in charge of the computer center. I had shredded a spool of their expensive ink ribbon and put the line printer out of action for the rest of the day - pending a service call from Univac.

      What no one had told me was that the line printer had a full width ink ribbon, and that it advanced only with a line feed. So it was getting banged on 12 times in quick succession and this was happening 100 times for each image printed.

      And that's how you cut an ink ribbon on a line printer...

      1. John Brown (no body) Silver badge

        Re: I crashed one of two graphics domains

        My worst was nowhere near as bad! I found the wide carriage daisy-wheel printer had program selectable character and line advance in fractions of an inch (1/72"??) and had a brilliant wheeze of using it as a plotter using only the full stop (period) character. I got a beautiful quality printout from a BBC Micro CAD package, far better than the cheap dot matrix printer could do. At least most of the way down the A3 page. The rest looked a bit sad as that was when I realised the daisy-wheel printer had a more expensive single strike carbon film ribbon[*] which had run out after printing many, many thousands of full stops instead the more usual few pages of A4.

        * For those younger readers or just unaware of printing history, unlike a cloth soaked in ink ribbon that was an endless loop you kept using until it was unreadable, carbon film single strike made a beautiful impression of each character strike but was more of an audio cassette or reel to reel tape which stopped moving when you reached the end. It also had security implications because if you unwound the reel you could read everting it had been used to print as the ribbon advanced a character space for each one printed.

    3. Uncle Slacky Silver badge
      Boffin

      Re: I crashed one of two graphics domains

      Not UKC by any chance? I remember watching fractals being generated in real time on the MCS there circa 1990.

    4. I could be a dog really Silver badge

      Re: I crashed one of two graphics domains

      the domain was locked to my session and could not be stopped without rebooting the whole MCS

      So the problem was actually that the system had a poor design, and so it was the user's fault. Hmm, sounds like Apple and the "you're holding it wrong" attitude to poor iPhone design.

      In an alternate reality, the admins would have said "well done for finding that design fault - we'll berate the vendor for a fix".

  3. Anonymous Coward
    Anonymous Coward

    Been there, done that

    In a previous life a colleague and I were doing some scheduled maintenance in our main server room AKA tidying up the cabling mess that had manifested itself over the years.

    The network featured many VLANs including at least 2 for voice.

    Our main PBX servers were in this room and plugged into ports which had the correct voice VLAN configured. At the end of the maintenance we decided on a whim ("while we're here") to move the PBX servers to different ports in the rack because it resulted in a shorter, neater cable path. I configured the ports by untagging the appropriate voice VLAN, we moved the connections and went on our way.

    Not long after, we started getting calls that PCs were not working properly. It took us some time to work out what had happened, but we eventually discovered:

    The old ports were correctly configured with the untagged VLAN and nothing else.

    The new ports had the correct untagged VLAN but all the other VLANs were tagged - (in my defence this was the default for a switch interconnect port)

    Our PBX ran its own DHCP server

    The PBX DCHP server didn't understand VLAN tags and was responding to ALL DHCP requests, not just the handsets.

    The consequence was that some (but not all) DHCP requests on a tagged network was being responded to by the PBX, breaking connectivity to the client that received it.

    I think we managed to convince management it was something else but it took way longer than it should have to work out what was going on...

  4. Pete 2 Silver badge

    Been there

    > Don doesn’t know how the uni tech team figured out he was the culprit

    Maybe the university's network bod was a graduate of "Don's" class and recalled this particular exercise.

  5. Anonymous Coward
    Anonymous Coward

    I was asked to set up some Citrix testing many, many moons ago on a test network. I was a little surprised when someone ran up to my desk and told me I'd taken down a large part of the Production Citrix estate. Turns out the network I was told was isolated really wasn't. Luckily for me I was able to point to an email where I'd been given the work, confirmed the network was (allegedly) isolated and would not cause issues.

    Fun times all round that day!

  6. Bebu sa Ware
    Windows

    dhcping

    Given demonstrator Don is now a Professor this could have happen 30 years ago or longer if he meant Unix rather than Linux. In any case campus networks pre 2000 were pretty rough and ready. Pay way too low to attract or retain networking experience or talent - it was the .com boom so just knowing the difference between 10Base2 and 10BaseT made you an expert.

    This disaster movie was pretty common once consumer wifi routers were petty cash purchases.

    Students would bring in their old routers to connect their phone or notebook to the local LAN for internet access or figured, logically I suppose, that the RJ45 LAN ports were as good as switch as any for offices chronically under provisioned with Ethernet ports.

    These renegade DHCP servers were a nuisance interfering with departmental servers but given those two redundant servers were a lot faster than the consumer grade rubbish, clients normally got or renewed a legitimate lease (every 6 hours.) The departmental LAN was strictly firewalled from the campus network so little risk of a visitation from the glaring tech.

    Usually running dhcping to flush out these blighters and arpwatch to detect new devices on the network. Being able to track the MAC address to the switch port and thence to the physical location lent one an air of omniscience which encouraged good behaviour.

    Needless to say when it came to connecting unauthorised equipment to the network the staff were the worst offenders having lost their innate fear of heights and open windows.

    The last rogue DHCP server I encountered a few years ago was an i-phone bridged through a desktop onto the local wired network. I never knew the details as it was quickly located by others, using the MAC address I provided, who never revealed the who, what and where.

  7. jake Silver badge

    In late 1977 ...

    ... I managed to take down all the PDP10 kit at Stanford and Berkeley with a kernel upgrade ("It's just a couple of lines of code. It'll be fine. Ship it!"). Effectively split the West coast DARPANet in half for a couple hours. Not fun having bigwigs from Moffett and NASA Ames screaming because they couldn't talk to JPL and Lockheed without going through MIT ... At least the network managed to handle the damage and route around it.

    1. that one in the corner Silver badge

      Re: In late 1977 ...

      > At least the network managed to handle the damage and route around it.

      > Not fun having bigwigs from Moffett and NASA Ames screaming

      "Respectfully, Sir, we will resume normal operations just as soon as our resilience tests of the DARPA National Infrastructure has been completed. No, Sir, that is within the parameters for 'an unscheduled spot test' as per SOP. Good day, Sir."

      {Click}

      {Typing noises as a Notice of SOP suddenly appears and gets backdated a week, with annoyed note about ensuring the mimeograph is working}

    2. rcxb Silver badge

      Re: In late 1977 ...

      At least the network managed to handle the damage and route around it.

      The damage was me...

      *I* was the damage...

    3. IvyKing Bronze badge

      Re: In late 1977 ...

      I was at Cal in 1977 and don't recall hearing about any PDP10's on campus, though don't know about LBL. I was aware of two PDP-11s on campus at that time, one in Evans Hall (bought in part to replace the CDC-6400 B machine) and one in Corey Hall. The latter was where I had my first exposure to writing programs on a CRT terminal (Hazeltine).

  8. Autonomous Mallard

    The ISP I have the misfortune of dealing with at work fouls up their config management about twice a year and both enables DHCP and disables our static IP bloxk. Every time, I have to spend at least an hour escalating to a tech that understands what a static address *is*.

  9. goblinski

    Why am I the only one thinking an ipconfig would have found the dhcp server's IP address, and a subsequent nslookup would have found its host name, and that the minimum any IT should know is the existence of ipconfig (I've heard about it), ping (I even know one single switch for it), nslookup (I had to google it), and WHERE EVERY #$@$#@ COMPUTER IS PHYSICALLY LOCATED :-D

    How is the finding of the culprit the mystery here ?

    1. Anonymous Coward
      Anonymous Coward

      > Why am I the only one thinking an ipconfig would have found the dhcp server's IP address, and a subsequent nslookup would have found its host name

      I didn't downvote but will give you an answer, which is simply that a DHCP server is not a DNS server. It can hand out addresses but it doesn't add them to DNS nor create the necessary reverse DNS record needed to find a name from an IP address.

      Most likely the BOFH sent out a DHCP request packet, saw where the response came back from and knew which switch handled that bit of the network.

      1. goblinski

        Vast thanks :)

        I am an absolute network muggle, and I guess what I described above wouldn't have worked the way I guessed it.

        However, my point was that "Don" was not a nefarious operator, and I wouldn't expect him to have obfuscated/hidden his newly crafted DHCP server in any way, or cloned mac addresses or anything such.

        If anything - it would have been nicely labeled. Hence my puzzlement.

  10. Giles C Silver badge

    Had it happen to me

    This is back in the okd thin client days so early 2000a which used a bit of wyse software to configure them.

    Someone rigged up a “server “ and loaded the software on to image a load of clients. This was all dropped into one of prod vlans for the office.

    The server had a dhcp module configured and so when the machines restarted the next morning they got an up from that instead of the main dhcp server for the site. Took me about 20minutes to figure that one out and locate the server - once I had found the MAC address then traced the cable to the machine etc.

    Was not impressed.

    Gone back to the article thecc cv entire network must have flat otherwise the blast radios should have been contained to a single vlan or segment?

    1. Giles C Silver badge

      Re: Had it happen to me

      Knew I shouldn’t have written that whilst walking on a cold day. It should, have read….

      This is back in the okd thin client days so early 2000s which used a bit of wyse software to configure them.

      Someone rigged up a “server“ and loaded the software on to image a load of clients. This was all dropped into one of prod vlans for the office.

      The server had a dhcp module configured and so when the machines restarted the next morning they got an IP address from that instead of the main dhcp server for the site. Took me about 20 minutes to figure that one out and locate the server - once I had found the MAC address then traced the cable to the machine etc.

      Was not impressed.

      Gone back to the article their entire network must have flat otherwise the blast radios should have been contained to a single VLan or segment?

  11. Anonymous Coward
    Anonymous Coward

    Got the T-shirt

    When I was teaching myself about IPv4, I coded some ARP and RARP servers on my PC to get a better understanding of low-level packets. That ultimately screwed the entire company at a level more fundamental than DHCP.

    It was perhaps the fastest power cycling re-boot I ever performed, with everyone else then having to follow suit.

    "Must have been a Windows glitch" saved my bacon.

  12. DoContra
    Pint

    I was at both sides of that desk once :)

    This happened at my work (University adjacent). About 12 years ago at work, dunno what was the issue the punter had but I solved it by setting up a shared connection in Ubuntu (with NetworkManager), and having them connect to the internet via Wi-Fi. ~1 month later, I had an intermittent issue with a rogue DHCP server on the network that I couldn't make heads or tails of. One day in anger I traced the suspect switchport[a] and disabled it via software. Within a week I had the main suspect on my office complaining about not being able to use the port; I enabled it and went to their desk to find the shared connection was coming up by default. After admonishing them (while taking my fair share of the fault), I disabled autoconnect on the shared connection and showed them how to check if they were using the correct connection. Within the year I configured every switch I could get my grubby hands on the admin console with the allowlist of ports that may send DHCPREPLY packets.

    [a]: Luckily it was on one of the switches I could admin back then,but that's a different story.

  13. Vincent Manis

    Violating Computing Centre rules

    Back around 1980, our University Computer Centre decided that it existed for the purpose of solving differential equations, not word processing. So the Centre's newsletter ran an article entitled “The Computer Centre Is Not A Print Shop”, explaining that using the central computer for word processing was a misuse. I was teaching an introductory CS course at the time; the first assignment was typically some version of “Hello, world!”. My first assignment was for the students to write a paragraph explaining their reason for taking CS, and use the (then quite wonderful) Michigan Terminal System to format it. I fully expected to receive a blast from Centre management (with whom I was on friendly terms), but there was nary a query or comment when a hundred or so of these jobs rolled off the university's IBM 3800 laser printer.

    Being a born rebel, I was disappointed.

  14. Anonymous IV
    WTF?

    Staggered...

    So what happened to the maxim the network problem is always DNS??

  15. jimbo60

    Not even our fault...

    Similar result, but different cause: years ago, installed a VM from some vendor because that was how they delivered their product. The VM came up with a live DHCP server exposed to the company network, resulting in the expected chaos.

    That mistake was never repeated.

    1. Andrew Scott Bronze badge

      Re: Not even our fault...

      Someone once connected a apple wireless router to a port in an office on campus, caused everyone in range to come up with a private unroutable ip address. called it in to ITS when people started complaining that they had lost their internet access. Most computers were on ethernet at the time very few using wifi except macs. Didn't have a campus wide wifi network yet. so in trying to add wifi to his office killed all the ethernet connected computers in range.

  16. Harry WWC

    it happens with student machines too

    had a similar issue happen in a Tech College (TAFE) here in australia a while back.

    One of the classes (not one I taught - this time) was to install a windows server VM and a windows client VM and have the client pickup the dhcp address (and other dhcp settings) from the server.

    except (of course) one student reconfigured their VM network and went into 'bridged' mode.

    of course, after a while - after the class was finished and the students had left - the local IT support guy comes in not happy about a rogue dhcp server from "that room". of course, we couldn't log on as the student, and many had just locked the machine and left their session (and VMs) running.

    so, mad panic "what do we do???"

    I just started walking around, press and hold the power button until each machine had shut down - "there, fixed". and then suggested the teacher have a good hard talk with the class about rogue dhcp servers. did anyone lose work? maybe. don't care. needs must.

    1. Ishura

      Re: it happens with student machines too

      I may or may not have done something similar at my work. I'd set up a VM and had configured a DHCP server on it, and then started hearing "is your network working?" from various people in the office. I was confused, because my VM was definitely _not_ set to bridged mode... but software isn't bug-free so I reached around the back of the machine and yanked the Ethernet cable anyway.

      I honestly don't remember whether that immediately fixed connectivity again or not, but every time I booted up that VM over the next couple of days I was sure to disconnect the cable first, just in case!

  17. Bernard Peek

    Oooops!

    A friend started learning computing at Hatfield Polytechnic as it was then. He wrote his first BASIC program and submitted it to their PDP10. He was learning about loops. They hadn't yet come to the part of the syllabus about terminating infinite loops.

  18. RosslynDad
    Thumb Up

    Momentary Lapse of Reason

    Loved the Pink Floyd references, Simon.

    1. Roland6 Silver badge

      Re: Momentary Lapse of Reason

      Also “ Hey! Teacher! Leave our network alone!”

  19. DownUndaRob
    WTF?

    100% CPU in WinFrame.

    Picture a lab running diskless workstations, on a WinFrame based environment

    Imagine a lecturer teaching student programming, in BASIC

    Teaching about loops.

    10 GOTO 10

    and run...

    CPU Load goes 100% and stays there, everything slows to a crawl, even ctrl-alt-delete wont work.

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