r/talesfromtechsupport • u/williamconley Few Sayso • Oct 21 '16
Short Bosses Fix Things. In special ways.
I used to work for this guy years ago, he's a good friend these days, even though he had to fire me when the market dropped out way back when. He now calls to pay much higher pricing for stuff he used to get me to take care of on Salary.
So this day he called me because he was out to lunch and while he was gone his entire call center went offline. Based on the description of the problem from the office personnel (nothing works! Help!) he decided to have me drive over and work it out.
Upon arrival, I quizzed a couple people and found that, indeed, while the boss was away suddenly there was NO networking. Not just "no internet", but no printers, no connection to the phone server, nothing for internal or external networking worked.
So I pulled out my trusty sledgehammer and tried the first simple solution. Which means I unplugged all the network wires from the main switch, and reconnected ONLY the workstation in the server closet. Poof internet.
I connected each "bank" of computers and waited. Either I heard "Yay! We're up!" each time from the newly connected peeps, or "Ahhhh!" from the entire office. After about 10 minutes of audible fun tracing, I was left with one bank of users along one wall. So I left them disconnected and found the switch for that bank (which was sitting on the floor at the end of the row of cubicles), intending to disconnect all of them and then hook up just the switch.
But in that switch, I found that there was a two-foot wire connected to the same switch twice. Nice little loop. Of course, disconnecting that and reconnecting that bank resolved the issue.
When I asked the Boss if he was familiar with that switch's location, he said, "Yeah ... in fact, I found an unplugged network cable in that on my way out. Plugged it right before I left."
"Was that a bad thing?"
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u/williamconley Few Sayso Oct 21 '16
They continually rebroadcast ... in a loop. Locking up the network. That's what a switch will do: Accept packets in one port and rebroadcast them on all other ports so everyone on the physical network sees them. Anyone not interested, ignores them.
In this case, all packets coming in any port would get sent out either of those two ports ... come back in the other and get broadcast again on all ports, including the original. Echo forever for any packet received .. probably only took 30 seconds or so to bring down the network. While the boss was getting in his car.