Quick questions about OSPF retransmissions. I am hitting the books on OSPF right now but wondering if anyone knew off hand if a high number of retransmits are normal? Asking because yesterday all of the sudden OSPF became unstable across the network causing neighbors to bounce for hours with no real root cause found. We clean up some config last night and upgraded to the latest 6.49.13 code just to make things more consistent and up to par. Most of the routers are CCR1009 or CCR 1036s.
One thing I am going to be looking at is the MTU on the links
Typical OSPF Config
/routing ospf instance
set [ find default=yes ] distribute-default=always-as-type-1 redistribute-connected=as-type-1 redistribute-static=as-type-1 router-id=208.40.222.254
/routing ospf interface
add interface="ether5 Apps Backhaul" network-type=point-to-point
add cost=100 interface="ether8- NewLenox Backhaul" network-type=point-to-point
add cost=100 interface="ether3 - Speedway Backhaul" network-type=point-to-point
add interface=ether4-cr2.lockport.il network-type=broadcast
add interface=Loopback0
/routing ospf network
add area=backbone comment=tr1.NewLenox network=208.40.222.192/30
add area=backbone comment=CR2.Lockport network=208.40.222.132/30
add area=backbone comment=Speedway network=208.40.222.240/30
add area=backbone comment=CR2.OrlandPark network=208.40.222.164/30
add area=backbone comment=loopback network=208.40.222.254/32
Log Message
13:49:50 route,ospf,debug Originate AS-External LSA
13:49:50 route,ospf,debug prefix=192.168.0.0/24
13:49:50 route,ospf,debug Installing an LSA
13:49:50 route,ospf,debug lsa=AS-External LSA id=192.168.0.0 originator=208.40.222.254 seqnum=0x80000017
13:49:50 route,ospf,debug old=AS-External LSA id=192.168.0.0 originator=208.40.222.254 seqnum=0x80000016
13:49:50 route,ospf,debug Adding to neighbor’s retransmit list
13:49:50 route,ospf,debug lsa=AS-External LSA id=192.168.0.0 originator=208.40.222.254 seqnum=0x80000017
13:49:50 route,ospf,debug neighbor=208.40.222.4
13:49:50 route,ospf,debug number of retransmits=178
13:49:50 route,ospf,debug Adding to neighbor’s retransmit list
13:49:50 route,ospf,debug lsa=AS-External LSA id=192.168.0.0 originator=208.40.222.254 seqnum=0x80000017
13:49:50 route,ospf,debug neighbor=208.40.222.16
13:49:50 route,ospf,debug number of retransmits=178
13:49:50 route,ospf,debug Adding to neighbor’s retransmit list
13:49:50 route,ospf,debug lsa=AS-External LSA id=192.168.0.0 originator=208.40.222.254 seqnum=0x80000017
13:49:50 route,ospf,debug neighbor=208.40.222.21
13:49:50 route,ospf,debug number of retransmits=178
13:49:50 route,ospf,debug Adding to neighbor’s retransmit list
13:49:50 route,ospf,debug lsa=AS-External LSA id=192.168.0.0 originator=208.40.222.254 seqnum=0x80000017
13:49:50 route,ospf,debug neighbor=208.40.222.2
13:49:50 route,ospf,debug number of retransmits=178
13:49:50 route,ospf,debug Deleting an LSA
13:49:50 route,ospf,debug lsa=AS-External LSA id=192.168.0.0 originator=208.40.222.254 seqnum=0x80000016