Work network problem

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Xarpolis

Life's a Dream
14,053
15,565
Hey guys, I have a problem that I can't figure out. Maybe one of you have run across something similar in the past.

On Wednesday morning, when we came in to work, or network was grinding to a halt. Less than dial up speeds. We were online, but almost everything internet based was timing out.

We called our provider and they verified everything was running great I their end. If we connect a single computer into the modem, it flies. Yet the moment we connect the wireless router, everything grinds to a hault. We figured that meant the router was faulty, so we bought a brand new one. Same problem.

As it stands, we have 7 computers, a credit card machine and security cameras connected into the router via a switch.

What could be causing the problem?

Thanks in advance.
 

Crone

Bronze Baronet of the Realm
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3,201
Check for a physical loop. Something coming out of the switch and back into it via another port.
 
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Frenzied Wombat

Potato del Grande
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31,802
Assuming you plugged a laptop directly into the router to test, I would say a duplex mismatch between the modem and router. If you're testing farther downstream, it could be a number of things, including the broadcast storm mentioned above.

If you aren't testing directly from a port on the router, do so. If speed is fine, then it's your downstream switch-- either a duplex mismatch between the router/switch, or a network loop causing a broadcast storm. If it's the latter, you don't even need to test-- all ports on your switch will be lit up like a christmas tree.
 

Sequeli

Silver Knight of the Realm
268
30
Sounds like a broadcast storm from a malfunctioning NIC or spanning tree loop on the switch. Connecting a computer up to the switch while it's at dial-up speeds then running a Wireshark capture may help yield some information as to the culprit.
 

Frenzied Wombat

Potato del Grande
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31,802
Sounds like a broadcast storm from a malfunctioning NIC or spanning tree loop on the switch. Connecting a computer up to the switch while it's at dial-up speeds then running a Wireshark capture may help yield some information as to the culprit.

Wireshark is obviously beyond his skillset if he's here asking for help on this type of problem. Plus, a spanning tree loop/broadcast storm won't require wireshark-- your entire network stack will look like a christmas tree. IMHO this really sounds like a duplex mismatch-- seen it more times than I can count, though it's typically between a workstation and a switch.
 
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a_skeleton_03

<Banned>
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So do this methodically.

Plug in the router and log into it and disable the wifi. Plug the same computer into it that you did straight to the modem. Check speeds.

If slow, reset router to default factory and also upgrade the firmware if there is one out and check again. Still slow? Buy a new one.

If it wasn't slow with the single PC start adding in items on at a time starting with wired. When you get to being slow again unplug what you just plugged in. Double check you are back to full speed then plug it back in. Slow again? Look at that device for malware, viruses, or firmware issues.

Then reenable wireless and change the wifi password. Start adding in clients one at a time with the new password. Same process as wired.

You should be able to pinpoint the issue doing this, I would also change the admin password on the router just in case.
 
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Xarpolis

Life's a Dream
14,053
15,565
Ok, we have 3 network items in play.
Cable modem
Wireless Router
Switch

Modem is connected directly to the router.
Router has 3 connections. The switch, the credit card machine and 1 person's pc.

The switch has 6 pc's, & the security cameras.

That's the entire system. No physical loops. It's just dragging. Typically the router only has 1 connection and everything is plugged into the switch, but we've been moving shit around because it doesn't work.
 

Frenzied Wombat

Potato del Grande
14,730
31,802
Alright, so I assume the "1 person's pc" that is plugged into the router is crawling as well? What is the duplex/speed of the router port attached to the modem. Is the router a consumer model or a Cisco/Juniper?
 

Xarpolis

Life's a Dream
14,053
15,565
It's called "The Bathroom Store". They sell higher end toilets, faucets and all that good stuff. Primarily the brand Toto. And the Linksys was purchased yesterday with the start of the problem. Before I made that post.

We "kindof" fixed it. Turns out the security cameras were causing all the problems. We disconnected them and it's flying once more. Still need to figure out why they're fucked up, but it'll happen soon.
PS - Thanks a_skeleton_03, your advice is how we figured out it was the cameras.
 

chaos

Buzzfeed Editor
17,324
4,839
It's called "The Bathroom Store". They sell higher end toilets, faucets and all that good stuff. Primarily the brand Toto. And the Linksys was purchased yesterday with the start of the problem. Before I made that post.

We "kindof" fixed it. Turns out the security cameras were causing all the problems. We disconnected them and it's flying once more. Still need to figure out why they're fucked up, but it'll happen soon.
PS - Thanks a_skeleton_03, your advice is how we figured out it was the cameras.
A lot of different cameras being compromised and becoming part of botnets lately. Could be the case here, should look into it, or at least segment off your cameras/IoT shit.
 
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a_skeleton_03

<Banned>
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Yeah not sure that Xarpolis Xarpolis has a switch that can do a VLAN. If you do let us know the brand so we can help you type in what to do.

The basics of it is that a VLAN will keep the cameras separate from the rest of the network and not allow them outside to the internet if that's what you desire.
 

Mist

Eeyore Enthusiast
<Gold Donor>
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Almost certainly those cameras are compromised, would explain everything.