Windows – custom route not working on windows

My windows laptop is directly connected to 192.168.1.0/24 (wireless lan). I access 10.21.0.0/16 though a router that is connected to both networks. The routing works fine with this configuration.

I have a VPN, that connects to 10.0.0.0/8. The VPN network doesn't actually use any IPs in the 10.21.0.0/16 range. So I should be able to configure my routing table to route all the 10.21.0.0/16 IPs through the wireless lan, and all other 10.0.0.0/8 through the VPN.

My understanding is that I can do this if the metric for the 10.21.0.0 is lower than that of the 10.0.0.0. The VPN (10.0.0.0) is automatically assigned metric 20. I have manually assigned the WLAN a metric of 1. I manually add an entry to the routing table with this command:

route add 10.21.0.0 mask 255.255.0.0 192.168.1.201 metric 1

The route is then assigned a metric of 2 (which is expected).

The problem is that it doesn't work. I can't ping any machine on the 10.21.0.0 network. But I can access other stuff on the 10.0.0.0. I can also access stuff on the 192.168.1.0.

To debug this i've done the following.

1. Run tcpdump on the router (192.168.1.201). I can verify that no packets for 10.21.0.0 arrive on that interface.
2. Disable iptables on the router. Disable the windows firewall.
3. Run wireshark on my laptop, to try and see which interface the ping requests go to. But I can't see them go anywhere!!
4. The ping command doesn't receive any 'destination unreachable' messages.

Here is the relevant section of the routing table.

IPv4 Route Table
===========================================================================
Active Routes:
Network Destination        Netmask          Gateway       Interface  Metric
          0.0.0.0          0.0.0.0    192.168.1.201     192.168.1.18      2
         10.0.0.0        255.0.0.0         On-link      10.55.44.203     20
        10.21.0.0      255.255.0.0    192.168.1.201     192.168.1.18      2

Update

As requested, here is the output of route print 10.21.0.1

C:\>route print 10.21.0.1
===========================================================================
Interface List
 17...02 50 f2 00 00 05 ......AGN Virtual Network Adapter
 16...a0 88 b4 e1 8f 20 ......Intel(R) Centrino(R) Advanced-N 6205
  1...........................Software Loopback Interface 1
 10...00 00 00 00 00 00 00 e0 Microsoft Teredo Tunneling Adapter
 11...00 00 00 00 00 00 00 e0 Microsoft 6to4 Adapter
 18...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter
 47...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter #2
===========================================================================

IPv4 Route Table
===========================================================================
Active Routes:
  None
Persistent Routes:
  None

IPv6 Route Table
===========================================================================
Active Routes:
  None
Persistent Routes:
  None

C:\>

Good catch, here is probably where the problem is. But alas, even adding a route for one specific host that I know is up, doesn't work.

C:\>route print 10.*
===========================================================================
Interface List
 17...02 50 f2 00 00 05 ......AGN Virtual Network Adapter
 16...a0 88 b4 e1 8f 20 ......Intel(R) Centrino(R) Advanced-N 6205
  1...........................Software Loopback Interface 1
 10...00 00 00 00 00 00 00 e0 Microsoft Teredo Tunneling Adapter
 11...00 00 00 00 00 00 00 e0 Microsoft 6to4 Adapter
 18...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter
 47...00 00 00 00 00 00 00 e0 Microsoft ISATAP Adapter #2
===========================================================================

IPv4 Route Table
===========================================================================
Active Routes:
Network Destination        Netmask          Gateway       Interface  Metric
         10.0.0.0        255.0.0.0         On-link       10.76.206.8     20
        10.21.0.0      255.255.0.0    192.168.1.201     192.168.1.18      2
       10.21.61.1  255.255.255.255    192.168.1.201     192.168.1.18      2
      10.76.206.0    255.255.255.0         On-link       10.76.206.8    276
      10.76.206.8  255.255.255.255         On-link       10.76.206.8    276
    10.76.206.255  255.255.255.255         On-link       10.76.206.8    276
   10.255.255.255  255.255.255.255         On-link       10.76.206.8    276
===========================================================================
Persistent Routes:
  None


C:\>ping 10.21.61.1

Pinging 10.21.61.1 with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.

Ping statistics for 10.21.61.1:
    Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

If I connect to the router (192.168.1.201) and run tcpdump, I don't see any packets to 10.21.0.0/16 on the interface that the laptop is connected to.