I configured remote access VPN to access Oracle DB server (I have two group ADMIN and CLIENT, this access for Client group only).A client application has be installed on VPN client's laptop and I have allowed port 1521 (sqlnet) on the firewall. But though users were able to connect VPN they cant access this oracle form and DB in it.
However when I open all the ports on the same server (IP level) it was able to access the applicaiton.
Here is please find attached configuraiton.
Are there any other ports to be open other than sqlnet (port 1521)?.