Hi folks
I'm trying to understand a problem I have with a GRE setup and I've reached the end of my own ideas. I need som help.
It's a router to router setup using Cisco 1921 connected using a 4G aggergation device. On the link created by the aggregator I'm running a GRE tunnel between the routers and then OSPF in the tunnel to set up the routing between the routers.
The tunnel is up and OSPF is FULL so that's all good. The 4G aggregation has an MTU of 1440 and unless I set the ip tcp adjust-mss value to something near MTU 1350 on the client side of one of the routers, no traffic is sent to the clients. That's an oddity in it self but what I cannot understand is why I get a 3mbit/s download to the clients and 10 mbit/s upload. It's almost like there is something in my setup causing problems with the download.
Here's some of my config if that shares any light
Client side router
interface FastEthernet0.999
desc Interface_connecting_to_4G
encapsulation dot1Q 999
ip address 192.168.40.1 255.255.255.0
ip nat inside
ip virtual-reassembly
ip tcp adjust-mss 1300
ip ospf 1 area 2
no snmp trap link-status
end
interface Tunnel3
desc Tunnel_to_HQ
bandwidth 10000
bandwidth inherit
ip unnumbered Loopback1
ip ospf network point-to-point
ip ospf cost 1
ip ospf hello-interval 3
ip ospf dead-interval 8
ip ospf 1 area 0
tunnel source FastEthernet0.810
tunnel destination 194.112.9.204
tunnel path-mtu-discovery
end
HQ side router
interface Tunnel6
description Tunnel_to_remote_site
bandwidth 10000
ip unnumbered Loopback1
ip ospf network point-to-point
ip ospf dead-interval 8
ip ospf hello-interval 3
ip ospf 1 area 0
ip ospf cost 1
tunnel source 194.112.9.204
tunnel destination 172.16.10.5
tunnel path-mtu-discovery
Any ideas, and I'm happy to fill in any details as needed?
/Fredrik
