OMV is great and working well for me.
I know that a NAS is never supposed to be exposed on the Internet, but still I want to expose a few ports so I can control a few things remotely.
My ISP gives me a public IP address so I set up DDNS and fort forwarding rules on my router. For some reason remote access is not working, here's some TCPdump info on the OMV machine:
Visiting OMV using DDNS address on a device in the same LAN: you can see the incoming and outgoing packets
Visiting OMV using DDNS address on the same device but from Internet: you can see the incoming packets but no outgoing ones, it seems that my OMV machines receives the request but never responds.
I'm confused by this, appreciate all your help.