I updated my RUT240 to the latest firmware RUT2_R_00.07.01.4.
I believe the earlier firmware was RUT2_R_00.07.01.1. After this update RUT240 will no longer connect to my OpenVPN server.
Unfortunately I don't have physical access to the RUT240 right now.
When I use the SMS Utilities, I can confirm that RUT240 has data connection over mobile LTE network.
The OpenVPN client name on RUT240 is "HA18".
The SMS response to "vpnstatus" is "HA18 - Disconnected"
I have tried to send SMS "vpnon HA18", but that doesn't change the connection state.
In the OpenVPN servers log file there is no trace of RUT240 trying to establish the tunnel.
I can download /etc/config/openvpn and it looks normal. The file has "openvpn.HA18.enable=1".
The answer here
routing-issues-rut240-when-used-conjunction-openvpn-cloud
suggests, that the latest release breaks some setting "UDP traceroute??".
I therefore downloaded /etc/config/firewall, but I don't see anything wrong there. What exactly was meant by "UDP traceroute" in that post?