SSH connection protocol does not work well between VPN clients

Routers
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AR300M run the vpn client connect to vpn server(10.55.114.48)
you can config ssh login to 10.55.114.48, through the wan interface. as follow:

  1. ssh AR300M, add on route:
    ip route add 10.55.114.48 via 192.168.18.1 dev eth0.2

you can modify, the AR300M, wan interface"eth0.2", and the wan interface gateway is 192.168.18.1

  1. allow the forward, lan to wan, as:
    iptables -I FORWARD -i br-lan -o eth0.2 -j ACCEPT

or sample to test:
iptables -I FORWARD -j ACCEPT

now, ssh login through the wan interface.