[nsp] GRE tunnel not passibg traffic problem

[Krzysztof Adamski]

Hi All,

I have two sites connected through a flaky ATM link (telco is trying to
fix it, but it's very intermittent). Both location are also connected to
the Internet. I have setup a GRE tunnel using the outside IPs of the
routers. The tunnel is up and I even managed to get OSPF running through
it. The problem is passing traffic, once when I disabled CEF it started to
work, but after a while it stopped. Right now only the first packet of a
new flow will get through the tunnel.
On one end I have a 3640 running 12.1(19) and on the other end 7204
running 12.2(12f)

The GRE interface on 3640 is

interface Tunnel0
 ip address 10.222.1.1 255.255.255.0
 no ip redirects
 ip mtu 1476
 ip ospf authentication-key 7 1040B4E47
 ip ospf network point-to-point
 ip ospf priority 3
 no ip mroute-cache
 tunnel source Hssi3/0
 tunnel destination 166.159.89.46
!

The GRE interface on 7204 is

interface Tunnel0
 ip address 10.222.1.2 255.255.255.0
 no ip redirects
 ip mtu 1476
 ip ospf authentication-key 7 1040B4E47
 ip ospf network point-to-point
 ip ospf priority 3
 no ip mroute-cache
 tunnel source FastEthernet2/0.993
 tunnel destination 216.86.11.186
!

I'm guessing it has something to do with route-cache, I have put
"no ip route-cache" on both tunnel interfaces without any help.

What is the magic incantation to get this to work, or is there a better
way to interconnect both sites when the ATM link fails?

K