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Well .... I reset my ISP router, reconfigured it in bridge mode, connect it to 1043DN ... it's working .... OpenWRT get my public IP ...I don't understand ...
That is normal as your ISP router acts like a simple switch in this case and your OpenWRT gets the public IP. I guess the internet connection is also plugged into your internet router's switch port (not the WAN port) just like the OpenWRt router.
If you want to have your OpenWrt router behind the internet router I think either you need to configure static IP/default route on it, or you need to configure DHCP on the internet router and set your Openwrt router WAN port to be a DHCP client.
(Last edited by zaksza on 28 Feb 2017, 19:14)