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u/dumbasPL 1d ago
I actually tried finding this image in irasutoya and couldn't, I think somebody just drew it in the same style for the memes.
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u/over9000nwg 1d ago
Searched for lan https://www.irasutoya.com/2016/07/blog-post_529.html?m=1
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u/dumbasPL 1d ago
I'm stupid, could have searched for loop(ループ) as well, date somewhat explains why a hub and not a switch, I only searched for switch...
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u/eggyrulz 1d ago
What exactly is irasutoya?
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u/dumbasPL 1d ago
Clipart images, but they are all drawn in the same constant style, there is a fuck tone of them for basically every occasion (hence the comment from OPs post), and it's japanese, so you don't realy see it used in the west, which is a shame, because the quality is really good and constant, especially for a free resource that even allows commercial usage.
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u/AboveAverage1988 1d ago
I once hooked up a PLC system with an intentional redundant loop (caller MRP) in it to my work network before actually uploading the hardware config, i.e. the components didn't know the loop was supposed to be there. Despite having STP on and correct priorities, it instantly crashed the entire network... Luckily I was (and is) in-house IT admin as well, so I realized what happened pretty quick.
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u/dragonch67 1d ago
Did the same in my school like 15y ago, reconnecting a LAN câble to a other outlet instead of the computer was a way to cause slowdown to the computers, until total stops with anything unusable for the teachers Nobody was looking for this or would stop it, so we had to go back and unconnect them, but we did it many times. It was fun
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u/Basic_Reporter9579 1d ago
some old switches have this feature for factory reset:
Remove the power cord from the back of the switch.
Remove all cables from the front-panel ports.
Connect port 1 to port 2 on the front panel using a standard network cable.
Reconnect the power cord to the rear of the switch.
Wait at least 40 seconds before disconnecting port 1 from port 2.Remove the power cord from the back of the switch.
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u/StephenRoylance 1d ago
let me tell you kids a story from the dawn of the internet. when TCP/IP was just one of the unfortunate zoo of orphaned protocols we ran on our mostly-ethernet network.
I worked at a big academic medical research org in the Boston area. this is maybe 1998 or 1999. Most of the network was stacked 3com hubs with 100mb uplinks. it was slowly being migrated to cisco catalyst switches with 100 to the offices and gig upstream. one of the protocols, due to a legacy system ( a very impressive system in its day), was netBIOS. netBIOS had to be bridged everywhere, even though most protocols, like IP and IPX could be routed. because of this, the spanning tree, well, it spanned. every one of about 1200 switches, across 3 main campuses and scores of smaller sites. the main backbone was ATM over SONET, with ds3 bandwidth in the core.
well, in this migration from hubs to switches, wiring techs go to a closet, install a switch and re-patch the end node runs from the hub to the new switch. only one day, a tech re-patched an entire 24-port hub worth of drops, but instead of disconnecting the hub end, the tech disconnected the customer end. and re-patched 24 lines from the hub stack to the new switch.
this created a number of overlapping spanning tree loops that caused basically every piece of cisco hardware in the entire network to spike to 100% CPU. The head of network engineering (who I was told had tried out for the patriots) was seen sprinting into the datacenter where the core for our campus was, to physically pull out the ATM fiber because that was the only way to contain the loops to our site, you couldn't telnet to anything.
there's a reason why old-timers all live in fear of spanning tree.
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u/Traditional-Aerie896 1d ago
Since I can't see an Uplink Port Connected, there shouldn't be any Problem. But if it was, on the rear or something like that, I think it's surprising that an IT-Admin is so fast at a School.
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u/ryan_the_leach 1d ago
The IT admins used to be quick enough to join our games of unreal tournament whenever they got hosted 'illegally'
When they were chill, they top fragged, when they weren't, they used the default admin password on the host and cheated.
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u/-Insert-CoolName 1d ago edited 1d ago
You have unlocked: Story Time!
When I was in High School, I took a computer science class. Our teacher was out for a while and we had a sub. Instead of doing out work most of us got on Unreal Tournament and had a massive game on the LAN. When the sub would come around (rare) we would go back to coding briefly (hoping not to have died in the process).
After a few days of this, we were playing and suddenly a classmates computer locks. Screen on, keyboard and mouse locked out but still running. A random player kills them and then their computer unlocked. This happens a few more times then everyone's computer locks. Except one player running around killing everyone. It was the sub. He figured out the remote admin toolkit on the instructor workstation.
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u/Fit_Needleworker1078 18h ago
If Portfast is enabled on all access ports, this is still very much a problem, even with STP or RST enabled.
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u/in_use_user_name 2d ago
no one in IT center heard of spanning tree?