Old openwrt wan config:

Old openwrt wan config:
config 'switch_vlan' 'eth0_1'
        option 'device' 'eth0'
        option 'vlan' '1'
        option 'ports' '0 5'

config 'interface' 'wan'
        option 'ifname' 'eth0.1'
        option '_orig_ifname' 'eth0.1'
        option '_orig_bridge' 'false'
        option 'proto' 'static'
        option 'ipaddr' '192.168.0.3'
        option 'netmask' '255.255.255.0'
        option 'gateway' '192.168.0.1'