[Solved] Ping stops on WAN when WireGuard client is connected

It's not really clear what you mean by this.

  • Do you mean you cannot ping the WAN IP from a client?
  • Do you mean you cannot ping your ISP's gateway from a client?
  • The ping diagnostic tool in the LuCI web GUI doesn't work?

I think you mean: "I cannot remotely ping my WAN IP from the Internet once I enable the Wireguad interface."

Then in that case, any rules also apply to output on WAN too. Your ICMP Echo-Reply packets might be responding via the tunnel. You can use PBR (or add IP Routes and IP Rules without the PBR app) to only configure e.g. you LAN of 192.168.255.0/25:

config route
        option target '0.0.0.0'
        option netmask '0.0.0.0'
        option table '1' #<---number used, or add name to a file, see Wiki
        option interface 'vpn'

config rule
        option src '192.168.255.0/25'
        option dest '0.0.0.0/0'
        option priority '1' #<---IP Rule No - not same as table
        option lookup '1'#<--- table No

Since your WAN IP != 192.168.255.0/25, the ICMP Echo Reply should exit WAN as normal.

Additionally, you would then change:

option route_allowed_ips '0'