I'm glad to see that the openvpn plugin made it back in OMV 1.0 release (I stayed on OMV 0.4 for quite some time because of that). Many thanks to the developpers for their work.
Default configuration works like a charm but I think there is some room for improvement:
On routing aspects, by default the script sets for the client to route everything via the VPN (push "redirect-gateway def1 bypass-dhcp"). It would be great to be able to change this behaviour to only route the private subnet toward the VPN (push "route 192.168.x.0 255.255.255.0") while the rest is still routed to the initial default gateway of the client. A flag 'Default route to VPN' in the VPN network section of the OpenVPN plugin webgui which can be enabled/disabled would do the trick.
When somenone is connected, there is no status tab in the webgui showing connected clients. It would be nice to have an OpenVPN tab in Diagnostics > Services displaying a cat /etc/openvpn/openvpn-status.log to show connected users.
I've also noticed that the OpenVPN daemon's privileges is set to root. Is there a reason for not using the following options to reduce the OpenVPN daemon's privileges after initialization?
Regarding logging, the date format seems to be different than other logs, therefore, when reading OpenVPN logs from Diagnostics > System Logs webgui, the date wrongly shows UNIX EPOC date (01 Jan 1970). I don't know if this is something that can be fixed directly on OpenVPN level or if a workaround can be implemented on OMV to be able to display different kind of date format.