DynDNS with OpenVPN Interface Problem

[sepei]

Hello,

is there a bug with dyndns in combination with openvpn? I got the problem if I bind an interface of an openvpn connection (Maybe also other interfaces?) to dyndns it dont let me reconnect to the openvpn servers. When I set it up it works correctly but on the moment when I reconnect to the openvpn server while the ddns is activated something is blocking the connections. The connection ends here and then timeouts:

Nov 30 14:22:44   openvpn[75950]: /usr/local/sbin/ovpn-linkup ovpnc9 HIDDEN_VPNDATA init
Nov 30 14:22:44   openvpn[75950]: /sbin/ifconfig ovpnc9 HIDDEN_VPNDATA up

If I delete the DDNS-Rule I can reconnect as before and everything is working.

[sepei]

I just found out if the openvpn tunnel gives me the same IP then before then it lets me connect. So if the cached-ip on the DDNS-Page is same to the IP that I get from the vpn connection (Virtual Addr) then it works. The cached-ip is also red until the connection with the old IP is entablished. So does the DDNS somehow block the openvpn connection if I dont get the same virtual address anymore?

[sepei]

Hm anyone an idea? Or is opnsense with DynDns in combination with openvpn broken?