I have a router (R), a Windows 10 PC with routing enabled. R has two interfaces; one connected to a Wifi Link (192.168.0.203/24) which is a DLink Wifi AP (Wifi AP) and another connected to the openvpn (10.13.13.213/24).

The Wifi AP has static routes installed for the openvpn subnet 10.13.13.0/24 gateway 192.168.0.203, whereby all Wifi AP clients should reach the openvn subnet. Also, the Wifi AP has the IP address 192.168.0.13/24.

I have made this configuration numerous times at my workplace and elsewhere, but for some reason, my DLink Router seems not to work just right. The problem is, while I can ping the hosts on the Wifi Link to the Router with both the IP addresses of the router, pinging the hosts on the wifi link from the router with the openvpn address just does not work:

Pinging Hosts on wifi link from router with 192.168.0.203 works.

ping -S 192.168.0.203 192.168.0.113
Pinging 192.168.0.113 from 192.168.0.203 with 32 bytes of data:
Reply from 192.168.0.113: bytes=32 time=149ms TTL=64
Reply from 192.168.0.113: bytes=32 time=168ms TTL=64
Reply from 192.168.0.113: bytes=32 time=170ms TTL=64
Reply from 192.168.0.113: bytes=32 time=173ms TTL=64

Ping statistics for 192.168.0.113:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 149ms, Maximum = 173ms, Average = 165ms```

Pinging Hosts on wifi link from router with 10.13.13.213 does not work:

ping -S 10.13.13.213 192.168.0.113

Pinging 192.168.0.113 from 10.13.13.213 with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.

Ping statistics for 192.168.0.113:
    Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

Weirdly, ping to 192.168.0.13 (the Wifi AP gateway) works alright with 10.13.13.213 of the router:

ping -S 10.13.13.213 192.168.0.13

Pinging 192.168.0.13 from 10.13.13.213 with 32 bytes of data:
Reply from 192.168.0.13: bytes=32 time=1ms TTL=63
Reply from 192.168.0.13: bytes=32 time=1ms TTL=63 ...

That said, if static routes are installed on wifi hosts for openvpn subnet, ping work just fine. This suggests that my wifi AP which is an ultra-cheap device is the culprit. Can you guys here confirm for me if these devices are indeed like it or have some special configuration to be done, or my only options are to install static routes on every host?