[strongSwan] Can not start L2TP/IPsec connection from NetworkManager

[Sergei Naumov]

Hi!
I am trying to set up an IPsec connection through L2TP from NetworkManager:

ct  3 08:05:09 yarilo NetworkManager[623]: <info>  Starting VPN service 'l2tp'...
Oct  3 08:05:09 yarilo NetworkManager[623]: <info>  VPN service 'l2tp' started (org.freedesktop.NetworkManager.l2tp), PID 2211
Oct  3 08:05:09 yarilo NetworkManager[623]: <info>  VPN service 'l2tp' appeared; activating connections
Oct  3 08:05:09 yarilo NetworkManager[623]: <info>  VPN plugin state changed: starting (3)
Oct  3 08:05:09 yarilo NetworkManager[623]: <info>  VPN connection 'Safianovo' (Connect) reply received.
Oct  3 08:05:09 yarilo NetworkManager[623]: <warn>  VPN connection 'Safianovo' failed to connect: 'Cannot save /etc/ipsec.secrets'.
Oct  3 08:05:09 yarilo NetworkManager[623]: <warn>  error disconnecting VPN: Could not process the request because no VPN connection was active.
Oct  3 08:05:30 yarilo NetworkManager[623]: <info>  VPN service 'l2tp' disappeared

Is there any requirement for a specific permissions I have to have to run it or there is something more fundamental? I am using a NetworkManager's strongswan 0.9.3.6 and strongswan 5.3.3.

-- Sergei