Hi Need some help debugging some OSPF issue. I have some flapping on the data center network Bascially I have a backbone with 1 asa5520 4 CCR1036 4 RouterOS VM's I am using OSPF to get the routing done. After the issue in the morning I turn on ospf,debug,!raw to my syslog server. To see if I can find out what the issue was This seems to be unusual behaviour (I think), doesn't normally happen, seem to be re inserting known routes but with a different seqnum ? Aug 10 17:47:23 gsrtr1 route,ospf,debug gsrtr1: LSA Update received: Installing and flooding it Aug 10 17:47:23 gsrtr1 route,ospf,debug gsrtr1: header=AS-External LSA id=206.190.96.0 originator=10.43.255.2 seqnum=0x80001814 Aug 10 17:47:23 gsrtr1 route,ospf,debug gsrtr1: Installing an LSA Aug 10 17:47:23 gsrtr1 route,ospf,debug gsrtr1: lsa=AS-External LSA id=206.190.96.0 originator=10.43.255.2 seqnum=0x80001814 Aug 10 17:47:23 gsrtr1 route,ospf,debug gsrtr1: old=AS-External LSA id=206.190.96.0 originator=10.43.255.2 seqnum=0x80001813 Aug 10 17:47:23 gsrtr1 route,ospf,debug gsrtr1: Adding to neighbor's retransmit list Aug 10 17:47:23 gsrtr1 route,ospf,debug gsrtr1: lsa=AS-External LSA id=206.190.96.0 originator=10.43.255.2 seqnum=0x80001814 Aug 10 17:47:23 gsrtr1 route,ospf,debug gsrtr1: neighbor=10.32.255.13 Aug 10 17:47:23 gsrtr1 route,ospf,debug gsrtr1: number of retransmits=1 .... Aug 10 17:47:24 gsrtr1 route,ospf,info gsrtr1: Invalid sequence number Aug 10 17:47:24 gsrtr1 route,ospf,info gsrtr1: mine=587629 Aug 10 17:47:24 gsrtr1 route,ospf,info gsrtr1: received=587628 Aug 10 17:47:24 gsrtr1 route,ospf,info gsrtr1: Discarding packet: MD5 authentication failed Aug 10 17:47:24 gsrtr1 route,ospf,info gsrtr1: source=10.31.19.4 Aug 10 17:47:24 gsrtr1 route,ospf,info gsrtr1: Invalid sequence number Aug 10 17:47:24 gsrtr1 route,ospf,info gsrtr1: mine=581231 Aug 10 17:47:24 gsrtr1 route,ospf,info gsrtr1: received=581230 Aug 10 17:47:24 gsrtr1 route,ospf,info gsrtr1: Discarding packet: MD5 authentication failed Aug 10 17:47:24 gsrtr1 route,ospf,info gsrtr1: source=10.31.17.3 I'm not sure how they get out of sequence. The network is not being overly used ... If somebody can tell me if this is normal behaviour ... "install and flooding". Or its normal for when seq numbers get out.. What might be things that might through a seq out ? Also the network is very static.. so ... I have actually gone in and add static routes with metric 250 for 90% of the routes.. A