Network nerd help needed

[Ascender]

I know, but its been years since I let my technical qualifications lapse, so I’m not even pretending any more...

We have a gig Ethernet switch in the loft with most devices in the house on wired connections. There’s no strange devices, I guess the Hikvision IP cams may be the only thing that’s constant, but they’re wired back to the NVR.

The broadband router is downstairs and only has two Ethernet connections going in to it - one from the Ethernet switch and one for the BT WholeHome wireless discs. Wireless is disabled on the router.

When the switch is connected, it looks like “something” is impacting our broadband connection. So when I disconnect the Ethernet switch from the router, slowness disappears and speedtest results go up significantly.

I’ve tried disconnecting everything from the switch while its connected to the router and re-connecting things one at a time while running speedtests - results were inconclusive.

I ran a packet capture app but nothing stood out as being the likely culprit.

Any idea what I could do to narrow the issue down?

[scotta]

easiest way would be to reconnect the switch and systematically disconnect devices then run a speed test. The other option is running wireshark to see where the majority of the traffic on the network is coming from.


ETA - Start with the ip camera.

[Ascender]

It was Wireshark I was using. I’m also still not convinced that its as clear-cut as that.... Its so sporadic I’m wondering if its my broadband connection and I’m now trying to find an issue internally which explains the shit speed I’m seeing.

[scotta]

It was Wireshark I was using. I’m also still not convinced that its as clear-cut as that.... Its so sporadic I’m wondering if its my broadband connection and I’m now trying to find an issue internally which explains the shit speed I’m seeing.

Broadband has been all over the place recently so there's a very good chance that is the issue. Massive upsurge on traffic with the lockdown.

[Ascender]

It was Wireshark I was using. I’m also still not convinced that its as clear-cut as that.... Its so sporadic I’m wondering if its my broadband connection and I’m now trying to find an issue internally which explains the shit speed I’m seeing.

Broadband has been all over the place recently so there's a very good chance that is the issue. Massive upsurge on traffic with the lockdown.

Its been sporadically awful since before lockdown, but does seem to be shit more often than now now. Was wondering if its contention issues at the exchange.

Max I should get is 35MBps, typical is 25MBps. Today at times its been down to 1-3Mbps with only a couple of devices connected.

[Orange Cola]

What’s the time periods for the change in speeds? Do you need to leave things disconnected for 12/24/36 hours for example?

[mr_jon]

Something running at 10MB?

[Beany]

I'm gonna put a shiny penny on the main uplink cable to the switch being FUBAR - broken pair or something.

Check the error connection stats on the switch side (if it's managed and will let you do that) and see if it shows anything in there.

[Ascender]

No joy so far...

I’m starting to think the switch is a red herring and it’s the broadband which is knackered. Hmmm, or maybe something on the separate wireless network...

[Ascender]

I’m just working tethered to my phone today which is much quicker, will then strip everything back later and add one device at a time. Fun times.

[Ascender]

I’ve put the original EE router back-in, have enabled WiFi on it and disconnected the BT WholeHome discs from it.

I’m just adding devices one at a time to the WiFi hosted from the EE router.

Ethernet switch is connected - so I can run speedtests from the iMac.

At the moment, its been stable for a couple of hours with no speed drops.... Which is encouraging, but is making me wonder if there’s a rogue wireless device or its the WholeHome discs - maybe a faulty disc or something?

[drcarlos]

My virgin broadband has been up and down speed wise, from the 100mb we’re supposed to get right down to about 20mb at times (all measured off a cable at the router). None of the links are sized to deal with everyone being at home all the times so we’re back at the turn of the century when we had contention. Not saying there’s nothing else wrong but it doesn’t help when you are fighting on two potential fronts at the same time and intermittently to boot.
I’ve had a network adapter go funny on my daughters Laptop during this (not connecting on 802.11n) and had to swap that out for an older slower 802.11abg card so it connects reliably and doesn’t run like a pig, but at least it was only 1 endpoint device that was a real problem and not something in the middle.

[DeskJockey]

Virgin run quite high contention IIRC.

[Beany]

Virgin are fucking shit.

Fixed that for you.

[DeskJockey]

I'm trying to troubleshoot my own WiFi issues, so installed PRTG on an old laptop yesterday to see if I can get some decent data to help me figure out what the root cause it.