O gateway está errado. Ele deve residir na mesma sub-rede do seu IP. otherwhise não vai funcionar.
IP: 9.8.7.200
Netmask: 255.255.255.248 (/29)
Network: 9.8.7.200
Broadcast: 9.8.7.207
First IP: 9.8.7.201
Last IP: 9.8.7.206
Eu configurei minha ponte da seguinte maneira:
allow-hotplug eth0
iface eth0 inet static
address 1.2.3.4
netmask 255.255.255.0
network 1.2.3.0
broadcast 1.2.3.255
gateway 1.2.3.1
#(as is work with openvpn interfaces)
auto tap0
iface tap0 inet manual
pre-up openvpn --mktun --dev tap0
post-down openvpn --rmtun --dev tap0
auto tap1
iface tap1 inet manual
pre-up openvpn --mktun --dev tap1
post-down openvpn --rmtun --dev tap1
auto br0
iface br0 inet static
bridge_ports tap0 tap1
address 10.20.30.40
netmask 255.255.255.0
up route add -net 192.168.1.0 netmask 255.255.255.0 gw 10.20.30.101
up route add -net 172.16.25.0 netmask 255.255.255.0 gw 10.20.30.100
down route del -net 192.168.1.0 netmask 255.255.255.0 gw 10.20.30.101
down route del -net 172.16.25.0 netmask 255.255.255.0 gw 10.20.30.100
Todas as Redes do Cliente OpenVPN são roteadas e podem se conectar à Internet se usarem o IP do servres OpenVPN como gateway. (opção de gateway de redirecionamento)