Hello together,
at home I use a MikroTik-Router to route and switch my LAN and my VPNs.
As you can see, I have a AVM Fritz!Box-Router to use as a first Router and PBX.
I can’t use this Box as Modem because there is no PPPoE-passthrough functionality.
So I use the private 172.16.1.x/30 subnet between the Fritz!Box and the MikroTik Router with static IPs.
From the MT-Router I terminate a PPtP-Tunnel to a Hamnet-Router (Hamnet is an IP-based Network for Radioamateurs, exclusive using the 44.0.0.0/8 IP-Adress-Range).
Also I have a little Webserver installed at my DMZ (10.0.10.0/24), which is reachable from the Internet.
The Fritz!Box gives all requests from the Internet to the MikroTik-Router (MT is Exposed Host).
Additional the MT-Router is a OpenVPN-Server to give my external Clients Access to my Home-Network an to give them a secure Internet-Access.
Now the following Functions are given:
Access from every LAN-Client PC to the Internet
Access from the Internet to my Webserver
ICMP from every LAN-Client to the Hamnet (incl. DNS)
Acces from an OpenVPN-Client to the Hamnet
ICMP from every OpenVPN-Client to the Internet
The following Functions are not given:
Access from LAN-Client-PCs to the Hamnet
Access from an OpenVPN-Client to the Internet
Can anyone tell me about the Problem?
I can’t understand why I can PING and trace route to the Hamnet/Internet but why I can’t browse on any Homepage using a different Client.
Thank you for helping me, Michael
P.S.: I’m a MT Newbee, please consider that 
Edit: Please consider, that I used a external DSL-Modem before I used the Fritz!Box. The MT-terminated the PPPoE-Conn. to the Internet.
Every Function I described was given.
