на сервере
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         192.168.0.1     0.0.0.0         UG    0      0        0 eth0
10.8.0.0        0.0.0.0         255.255.255.248 U     0      0        0 tun0
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0

на роутере (DDWRT)
Destination 	Subnet Mask 	Gateway 	Flags 	Metric 	Interface
0.0.0.0	    	0.0.0.0		123.123.123.xxx	UG	0	WAN
10.8.0.0	255.255.255.0	192.168.0.10	UG	0	LAN & WLAN
123.123.123.123	255.255.255.224	0.0.0.0		U	0	WAN
169.254.0.0	255.255.0.0	0.0.0.0		U	0	LAN & WLAN
192.168.0.0	255.255.255.0	0.0.0.0		U	0	LAN & WLAN

на клиенте
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.8.0.1        0.0.0.0         UG    1024   0        0 tun0
10.8.0.0        0.0.0.0         255.255.255.248 U     0      0        0 tun0
192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 wlan0

с клиента
traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 60 byte packets
 1  10.8.0.1 (10.8.0.1)  3.538 ms  11.484 ms  11.816 ms
 2  DD-WRT (192.168.0.1)  11.834 ms  12.277 ms  13.727 ms
 3  * * *
 4  * * *
и так далее 30 раз.