Linksys EA8300 eth1 wan not working

Installing and Using OpenWrt Network and Wireless Configuration
6

I believe it is a known issue with IPQ40 devices.

For reference
https://forum.openwrt.org/t/ipq40xx-switch-config-strangeness/32542

See also
https://forum.openwrt.org/t/optimized-build-for-ipq40xx-devices/44125