OpenVPN and port forwarding

Question

openvpn

Good day! The following problem needs to be solved:
Available:
network #1 - 192.168.21.0/29
network #2 - 192.168.20.0/16 (!)
server (debian 7)
ETH0 192.168.20.55/16
ETH1 192.168.21.132/29
TUN0 10.8.0.1 ( Openvpn server)
Client #1
ETH0 192.168.20.33/16
TUN0 10.8.0.2 (OpenVPN client)
Openvpn client connects to the server at 192.168.20.55. It is necessary to make sure that connections to 10.8.0.1 (TUN0 on the server) on port 564 are forwarded to 192.168.21.130/29 (ETH1 on the server) on the same port.
The basic iptables recipes don't work.

Answer 1

Everything should work.

# echo 1 > /proc/sys/net/ipv4/ip_forward
# iptables -A INPUT -i tun0 -p tcp --dport 564 -j ACCEPT
# iptables -t nat -A PREROUTING -p tcp -i tun0 --dport 564 -j DNAT --to-destination 192.168.21.130:564