AT&T Fiber not playing nice with VPN?

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1

Hi All,

Been trying to diagnose an issue for a few months now and AT&T offers very little insight.

I currently have a 2gigabit fiber plan. I am using their provided gateway (Wi-Fi off) into my own router in AP mode. That router then provides wireless signal to the home, and feeds into a switch that gives Ethernet to each room.

I am dealing with constant disconnects. However they only occur when another resident of the home is using her work computer via hardwired/WiFi (when hardwired, it is running from a second switch to provide Ethernet to multiple devices in the office). Meaning an entire weekend of no work we will have zero disconnects. And once she starts working we can expect 2-3 per day during working hours. Her company has an AT&T VPN application, which I’m assuming is the culprit.

Does anyone have experience with a single device with VPN being able to bring down an entire home network?

AT&T is claiming it’s likely a bad port on their modem but I’m struggling to believe this given the pattern. I have also tried this with two devices as access points.

To reiterate the flow to her device:
ATT gateway → Nighthawk router → large Ethernet switch → smaller Ethernet switch → laptop.

2

You’ve got a Netgear device in the mix. I’d try replacing that and see if the problem persists.

3

Seems hard to imagine how a laptop running a VPN application could cause disconnections on other devices. An IP address/subnet conflict, perhaps?

Can you characterize the disconnects? Are devices losing their DHCP leases? Can you ping a site on the Internet? How about the AT&T gateway?

4

I am confused so asking for clarification.

  1. Is the ATT device purely a modem (or ONT for fiber) or a modem/router/AP combo? Is it routing traffic or in IP pass-through or bridge mode?
  2. Is the nighthawk router being used as just an AP or are router functions still enabled?

This really just sounds like a misconfiguration somewhere between the ATT device and the Nighthawk.

I have ATT fiber with the lame BGW-320 in front on my pfsense router. The Att box just passes my public IP to my router and nothing else. I then have that pfsense router plugged into a switch that connects to all sorts of AP’s, switches and other devices.

I use VPN’s on multiple devices and have no issues. Granted they are not “work ATT vpn’s”.

5

Is the vpn using the same ip address scheme as your network?

6

Ah so the nighthawk router acting as a access point and feeding into the switch is causing the issue?

Edit: I wonder if I go from the modem directly into the switch and use the nighthawk router solely for wireless.

7

What generally happens is all devices lose their connection. Then occasionally ill get connected to an ATT website mentioning I have no connection. I will look into the leases question as I am not sure how to check this.

8

So I think you’re correct. I the ATT was a modem/router for fiber (if I understand correctly the ONT is the device on the wall feeding this). From there is was plugged into my nighthawk router (in AP mode) then the nighthawk router fed into my entire hardwired system.

I have gone ahead and now gone directly from the modem/router into the network switch to feed the home Ethernet in all rooms. And the nighthawk router acts as an AP being plugged directly off another port of the modem.

I believe my mistake was having the modem/router feed into my AP, then using an AP port to into the switch.