Restarting the VPN network does not work after vpnc-disconnect

[feg2hi]

This behaviour may be ok, but for me it was surprising, because the very first start of the VPN tunnel does work after reboot of the system.

If there is an active terminal session connected to the client (LAN) via the main network and in parallel establised an VPN connection (via WLAN logged into guest network) the VPN will not get up again after it was disconneted on the terminal (LAN) by

vpnc-disconnect

and reports at the end:

   NAT-T mode, adding non-esp marker
   Received duplicated packet, dropping it!
   Received duplicated packet, dropping it!
vpnc: no response from target
Error: argument "via" is wrong: use nexthop syntax to specify multiple via

Troubleshooting Steps / Proof

Observed with vpnc version 0.5.3+git20220927-1

1. Exit all open terminal sessions.
2. Issue start (vpnc) and stop (vpnc-disconnect) by cron job. E.g. Within OMV you can use System/Scheduled Tasks, Certain date