Hi We have a customer who has 8 branches. 6 branches gre over ipsec tunnel is established with their headoffice without having any problem. Only problem is happening at 2 branches. recently we have implemented MPLS in our network and that customer all the branches are connected through MPLS vrf. 6 branches are connected through VLAN point to point ip with us and those branches are coming through layer2 switches upto PE router. rest 2 branches is connected through L2TPV3 router in between then through VLAN upto PE. the scenerio is
branch office ---->L2TPV3 Router fa0/1 xconnect------>L2TPV3 router Fa0/0 pseduowire-----> PE Router 1 VLAN----> PE Router2 VRF with same VLAN L2TPV3 router pseudowire-class ethernet encapsulation l2tpv3 ip local interface Loopback0 ip pmtu nterface FastEthernet0/1 no ip address ip route-cache flow duplex auto speed auto no cdp enable xconnect 10.10.10.254 110 pw-class ethernet ========================================== Customer branch router interface Tunnel1 description "headoffice" bandwidth 1024 ip address 111.2.1.6 255.255.255.252 ip mtu 1452 no ip route-cache cef no ip route-cache ip tcp adjust-mss 1360 no ip mroute-cache tunnel source GigabitEthernet0/0 tunnel destination 10.9.9.1 tunnel path-mtu-discovery customer headoffice interface Tunnel21 description "HO-BGRA-ALAP" ip address 111.2.1.5 255.255.255.252 ip mtu 1452 ip tcp adjust-mss 1360 ip ospf cost 10 tunnel source 10.9.9.1 tunnel destination 10.9.9.17 tunnel path-mtu-discovery problem is ospf neighbour is not getting up automatically if the router gets down. after clearing the ospf process tunnel is getting up. sometimes tunnel is getting down by giving the ospf too many retransmission error. before applying the MTU size we saw the debug ip ospf adjacency which was showing *Mar 14 17:03:00.493 BDT: OSPF: Send DBD to 172.24.24.1 on Tunnel1 seq 0x1605 opt 0x52 flag 0x3 len 1452 *Mar 14 17:03:00.493 BDT: OSPF: Retransmitting DBD to 172.24.24.1 on Tunnel1 [25] *Mar 14 17:03:05.502 BDT: OSPF: Killing nbr 172.24.24.1 on Tunnel1 due to excessive (25) retransmissions *Mar 14 17:03:05.502 BDT: OSPF: 172.24.24.1 address 172.21.1.9 on Tunnel1 is dead, state DOWN *Mar 14 17:03:05.502 BDT: %OSPF-5-ADJCHG: Process 100, Nbr 172.24.24.1 on Tunnel1 from EXCHANGE to DOWN, Neighbor Down: Too many retransmissions *Mar 14 17:04:13.666 BDT: OSPF: Rcv DBD from 172.24.24.1 on Tunnel1 seq 0x1EA0 opt 0x52 flag 0x7 len 32 mtu 1476 state EXSTART *Mar 14 17:04:13.670 BDT: OSPF: First DBD and we are not SLAVE *Mar 14 17:04:13.698 BDT: OSPF: Rcv DBD from 172.24.24.1 on Tunnel1 seq 0xF5D opt 0x52 flag 0x2 len 1452 mtu 1476 state EXSTART so we set ip MTU 1452 at branch office and headoffice tunnel. can someone help us what would be the MTU setting which will help to gets the ospf neighbour and tunnel up and running _________________________________________________________________ The New Busy is not the old busy. Search, chat and e-mail from your inbox. http://www.windowslive.com/campaign/thenewbusy?ocid=PID27925::T:WLMTAGL:ON:WL:en-US:WM_HMP:032010_3 _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
