Wireguard client not working

[meinereiner]

Hi all,

I'm struggling with getting traffic though wireguard running. I want to use the OpenWrt router as a Wireguard Client to connect to a Fritzbox.

I have set up the wireguard client, added peers and the tunnel seem to exist. But I cannot ping the other side. Both sides indicate that the connection is established.
From my network behind the OpenWrt router I can also establish the connection via a Ubuntu machine.

Any idea on how I can debug the issue.
Here the status:

Protocol: WireGuard VPN
Uptime: 0h 25m 40s
RX: 432 B (6 Pkts.)
TX: 1.17 KB (22 Pkts.)

[psherman]

This seems to suggest that you are getting a handshake. But let's look deeper.

1. Is your FB running OpenWrt or the vendor firmware?
2. Let's see your OpenWrt config.

Please connect to your OpenWrt device using ssh and copy the output of the following commands and post it here using the "Preformatted text </> " button:

Remember to redact passwords, MAC addresses and any public IP addresses you may have:

ubus call system board
cat /etc/config/network
cat /etc/config/firewall
wg show

[meinereiner]

I think I found something: It seems that the Fritzbox was routing the response to a wrong interface (other VPN connection that was inactive).
Once I cleaned up the other connections I got it working.
I will check it out the next days and get back once I find out it is not working properly.