How to configure the firewall for VPN PPP connections?

[Paul Smith]

On Wed, Feb 18, 2015 at 10:05 PM, Gordon Messmer
<gordon.messmer at gmail.com> wrote:
>>
>> How should one configure the firewall in order to be able to connect
>> from my machine (Fedora 21) to another machine (MS Windows) via VPN
>> PPP? Perhaps, after some updates, the possibility of establishing such
>> a VPN PPP has become blocked by the firewall.
>
> What type of VPN?  Both PPTP and IPSec/L2TP use ppp.  Neither should be
> affected by stock firewall rules if the Fedora machine is initiating the
> connection.
>
> You should check /var/log/audit/audit.log (and/or "setenforce permissive"
> and test again) for SELinux related errors.  Otherwise, probably
> /var/log/messages and /var/log/secure will have useful data.

Thanks, Gordon, for your reply.

The type of VPN is PPTP. With the firewall disabled, I can establish a
VPN connection, but if the firewall is enabled, no VPN connection is
possible.

Paul