L2tp stoped working

1

Hey. I was using l2tp VPN for last 2 years on NixOS with no problem. but after a week holiday I am not able to connect to it anymore. I didn’t update my system, I didn’t change configuration. I tried multiple different networks and the issue did not resolved so I pretty sure it’s not just my ISP decided to block me from using that VPN

here is the relevant part of my config:

  networking.networkmanager.enableStrongSwan = true;
  services.xl2tpd.enable = true;
  services.strongswan = {
    enable = true;
    secrets = [
      "ipsec.d/ipsec.nm-l2tp.secrets"
    ];
  };

here is the error message I get:

❯ nmcli c up TradeTech\ UK
Error: Connection activation failed: Unknown reason
Hint: use 'journalctl -xe NM_CONNECTION=49249247-9833-4554-b348-7e1fee65aa3b + NM_DEVICE=wlp3s0' to get more details.

and this is what I see in logs. I see one of those lines after each attempt to connect to the VPN (not all of them at once)

Jul 30 17:32:25 mars NetworkManager[1006]: <warn>  [1722349945.0812] vpn[0xfb22c0,49249247-9833-4554-b348-7e1fee65aa3b,"TradeTech UK"]: dbus: failure: connect-failed (1)
Jul 29 13:11:55 mars NetworkManager[1051]: <warn>  [1722247915.0042] vpn[0x1b08880,49249247-9833-4554-b348-7e1fee65aa3b,"TradeTech UK"]: failed to connect: 'Timeout was reached'
Jul 29 11:23:58 mars NetworkManager[1051]: <warn>  [1722241438.8186] vpn[0x1abbd50,49249247-9833-4554-b348-7e1fee65aa3b,"TradeTech UK"]: failed to connect: 'couldn't look up L2TP VPN gateway IP address '

what could be the problem ? how can I debug it ? I tried rebooting my system

2

Could it be out of storage?

3

I have 80Gb available and the rest of the system works just fine

4

what fixed the problem:

  1. recreating VPN connection from scratch (tweaking the original one didn’t helped)
  2. disabling Use Point-to-Point-Ecryption
  3. giving new connection a new name. when I was trying to give it the original name it would instantly break (even tho I would rename the original connection to something else)

I have no idea what caused it to break

1 Like