LMDE 5 - Browser Can't Load Any Website - VPN Mess-up

[Z_L]

Hello Everyone,

Running LMDE 5 on a Lenovo laptop. I have installed and tested RiseupVPN first. It worked for a day or two, but since I did not donate, on the third day it already started misbehaving, like automatically disconnecting etc. so I disconnected it and stopped using it.

Next I have paid for AtlasVPN and installed their app via the terminal. It has no graphical interface, and can be used only from the terminal. It did work well yesterday, but I did not disconnect the VPN before shutting the laptop down (not sure if I should have done that or not).

Today when booted the laptop, I was unable to load any website using any browser on it any more. Then I have attempted to disconnect atlasvpn in the terminal, and it reported that it was not connected to any VPN server. Then I signed out of atlasvpn, but that did not fix the issue. Next, I have uninstalled riseupvpn (even though it was not running) to make sure there is no conflict with the atlasvpn app. Still no luck. After that I have uninstalled atlasvpn app, restarted the laptop, but it still does not load any website.

Next, I have logged the network communication with Wireshark and attempted to access a website from the browser. There is network communication, and request was sent to the site, but the browser could not load anything (no response from that IP). I have then connected my other Acer laptop to the modem, and this works well, so there is no problem with my internet connection.

Apparently, the atlasvpn app has messed up my LMDE 5 system. What can I do to restore the internet communication with the browser?

By the way, after I purchased the AtlasVPN subscription, attempted to install their app, but it did not work. Then I contacted their customer service, they updated their install package, and then I was able to install and run it. So apparently this app is still in a kind of beta phase, at least the version for Debian. I have contacted the customer service again, but they are very slow with the response. If we can at least restore the browser function without the VPN that would be great, because I might need to repeat this fixing even later, if their app is so buggy.
Thanks.

Zoltan

[Z_L]

AtlasVPN also offers a free limited version of their VPN, and the app can be downloaded from here:
https://atlasvpn.com/vpn-for-linux

The app is the same for both free and paid access, so I think it can be used for testing.

[Z_L]

Here is the system report:

System: Kernel: 5.10.0-12-amd64 x86_64 bits: 64 compiler: gcc v: 10.2.1 Desktop: Cinnamon 5.2.7
tk: GTK 3.24.24 wm: muffin dm: LightDM Distro: LMDE 5 Elsie base: Debian 11.2 bullseye
Machine: Type: Laptop System: LENOVO product: 80TG v: Lenovo V110-15IAP serial: <filter>
Chassis: type: 10 v: Lenovo V110-15IAP serial: <filter>
Mobo: LENOVO model: LNVNB161216 v: NO DPK serial: <filter> UEFI: LENOVO v: 1MCN42WW
date: 10/26/2017
Battery: ID-1: BAT0 charge: 23.0 Wh condition: 24.0/24.0 Wh (100%) volts: 12.1/10.8
model: LGC L15L3A02 serial: <filter> status: Unknown
CPU: Info: Dual Core model: Intel Celeron N3350 bits: 64 type: MCP arch: Goldmont rev: 9
L2 cache: 1024 KiB
flags: lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 4377
Speed: 2285 MHz min/max: 800/2400 MHz Core speeds (MHz): 1: 2285 2: 2348
Graphics: Device-1: Intel HD Graphics 500 vendor: Lenovo driver: i915 v: kernel bus ID: 00:02.0
chip ID: 8086:5a85
Display: x11 server: X.Org 1.20.11 driver: loaded: modesetting unloaded: fbdev,vesa
resolution: 1280x1024~60Hz s-dpi: 96
OpenGL: renderer: Mesa Intel HD Graphics 500 (APL 2) v: 4.6 Mesa 20.3.5
direct render: Yes
Audio: Device-1: Intel Celeron N3350/Pentium N4200/Atom E3900 Series Audio Cluster
vendor: Lenovo driver: snd_hda_intel v: kernel bus ID: 00:0e.0 chip ID: 8086:5a98
Sound Server: ALSA v: k5.10.0-12-amd64
Network: Device-1: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet vendor: Lenovo
driver: r8169 v: kernel port: 2000 bus ID: 01:00.0 chip ID: 10ec:8168
IF: enp1s0 state: down mac: <filter>
Device-2: Realtek RTL8821AE 802.11ac PCIe Wireless Network Adapter vendor: Lenovo
driver: rtl8821ae v: kernel port: 1000 bus ID: 02:00.0 chip ID: 10ec:8821
IF: wlp2s0 state: down mac: <filter>
Bluetooth: Device-1: Realtek RTL8821A Bluetooth type: USB driver: btusb v: 0.8 bus ID: 1-6:2

[MiZoG]

Take this advice with a pinch of salt.
VPN providers differ from one another.

I had a similar but not exactly the same problem with ProtonVPN and not on LMDE but on main Mint.
Some sites (not all of em) became inaccessible when I started using ProtonVPN even when VPN was turned off.

I solved it by flushing DNS cache. See here.

What else you can do? Perhaps go through your network settings and toggle on 'n' off, "reset" settings.

[Z_L]

Take this advice with a pinch of salt.
VPN providers differ from one another.

I had a similar but not exactly the same problem with ProtonVPN and not on LMDE but on main Mint.
Some sites (not all of em) became inaccessible when I started using ProtonVPN even when VPN was turned off.

I solved it by flushing DNS cache. See here.

What else you can do? Perhaps go through your network settings and toggle on 'n' off, "reset" settings.

Thanks for the tip, I have flushed the DNS now, restarted, but it still does not work. I will wait a day or two for response from customer service and see if they can solve the issue, but there is a good chance I will have to reinstall the system

But even then, I will still have to try running their VPN app again, which will probably whack the system again, so before installing the app, I will back up a restore point, and in case of crash, I will simply revert back to that earlier still working point (hopefully that would work). So far, there never was a need for me to create backups.

[Z_L]

To update the progress: the customer service replied that they don't actually offer the service for Debian, but only for Ubuntu. Therefore, I had no other choice than to remove LMDE 5, and install LM Cinnamon. The VPN works on the Ubuntu version for now.

I suppose that this thread can be closed now, because there was really no simple solution for a case when a software spoils the system.