I woke up this morning and my router, a Linksys WRT1200AC with the firmware version "OpenWrt 19.07.1 r10911-c155900f66 / LuCI openwrt-19.07 branch git-20.029.45734-adbbd5c" didn't have a internet connection anymore. This happened before, back then I'm not sure what I did but I reset it a couple of times and restored the backup and suddenly it started working again so I didn't want to touch it until it breaks down again.
My setup is that I get Internet into the house via fiber and then I connect that cable to the yellow "Internet" socket with a ethernet cable. When I connect my laptop to it the laptop just gets a public IP address via DHCP and I can surf, but the router doesn't.
When I use ping in Diagnostics I get the error "ping: bad address 'openwrt.org'"
Traceroute from the command line gives me:
traceroute to 22.214.171.124 (126.96.36.199), 30 hops max, 38 byte packets 1traceroute: sendto: Network unreachable
The WAN Interface (connected to br-wan6) doesn't get any IP address and RX shows RX: 328 B (1 Pkts.)