[c-nsp] trunk over isp's private vlan

[Dan]

Hello,

I need to create a trunk between two of my 3550 switches which are 
interconnected over my isp's network.  I can establish the trunk but I 
cannot get any ip information across the trunk.  I have many other 
trunks setup but this is the only one I have across someone else's 
network.  Here is my config, its the same for both sides:

interface Vlan509
 ip address 10.9.9.24 255.255.255.0
 ip ospf cost 50
end

interface FastEthernet0/8
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 509
 switchport trunk allowed vlan 509
 switchport mode trunk
 no cdp enable
 spanning-tree portfast
end

sh interfaces trunk shows the vlan in spanning tree forwarding state

This is a redundant link that I have setup that is why the ospf cost is 50

What could be wrong?

Thanks,
Dan.