I have TP-Link Archer C7v5 running OpenWRT 18.06.02. Most of the settings are the default ones, except the password and WiFi network settings where I had to activate the wireless interfaces and configure SSIDs, passwords, etc. There is DHCP server enabled by default I get connection details over it for both Wifi and wired connection.
On either WiFi networks(2.4 and 5GHz) I have internet, but if I connect to one of the LAN ports, I don't have connectivity - no ping nothing. I get IP, gateway etc, from the DHCP server. I can also reach the LUCI interface.
Also under "Active DHCP leases" in Status/Overview, I see the host name of my machine when it's connected over WiFi. But when I connect it over the wired LAN, the host name is shown as "?". However, the rest settings are ok - it has IP, MAC and lease time.
I'm sure it's something related to the configuration and it's really easy to setup, but I couldn't find the setting.
Ok, after finding out that the issue is in my laptop instead of the router, I deleted the Ethernet Connection profile(I'm running Linux Mint) and I have internet over wired connection now. I also flushed the DNS with '$ sudo /etc/init.d/dns-clean start' .