GRE is configured over IPSec, the IPSec VPN is hub and spoke mode. The GRE interface is running OSPF. keepalive was disabled on GRE interface,
At the issue time, GRE interface on spoke can't receive ospf hello packets, but GRE interface on Hub can receive ospf hellow packet.
We need to "clear crypto ipsec sa" to recovery the ospf neighbor.
(7005-2) *[mynode] #show ip ospf interface tunnel 1
Tunnel 1 is up, line protocol is up
Internet Address 172.17.100.134, Mask 255.255.255.252, Area 0.0.0.0
Router ID 172.17.100.4, Network Type POINT_TO_POINT, Cost: 10
Transmit Delay is 1 sec, State PTPST, Priority 1
Timer intervals configured, Hello 10, Dead 40, Retransmit 5
Neighbor Count is 0
Tx Stat: Hellos
5160 DbDescr 2 LsReq 1 LsUpdate 163 LsAck 113 Pkts 5439
Tx Err: BufNull 0 BufCorrupt 0 NoMem 0 SendFail 0
Rx Stat: Hellos
4228 DbDescr 3 LsReq 1 LsUpdate 262 LsAck 13 Pkts 4507
LoopSend 0 RxVirtualLink 0
Rx Err: DisCd 0 BadVer 0 BadNet 0 BadArea 0 BadDstAdr 0 BadAuType 0
BadAuth 0 BadNeigh 0 BadPckType 0 BadVirtLink 0
IntfDown 0 MySource 0 Legal 0
(7005-2) *[mynode] #show ip ospf interface tunnel 1
Tunnel 1 is up, line protocol is up
Internet Address 172.17.100.134, Mask 255.255.255.252, Area 0.0.0.0
Router ID 172.17.100.4, Network Type POINT_TO_POINT, Cost: 10
Transmit Delay is 1 sec, State PTPST, Priority 1
Timer intervals configured, Hello 10, Dead 40, Retransmit 5
Neighbor Count is 0
Tx Stat: Hellos
5161 DbDescr 2 LsReq 1 LsUpdate 163 LsAck 113 Pkts 5440
Tx Err: BufNull 0 BufCorrupt 0 NoMem 0 SendFail 0
Rx Stat: Hellos
4228 DbDescr 3 LsReq 1 LsUpdate 262 LsAck 13 Pkts 4507
LoopSend 0 RxVirtualLink 0
Rx Err: DisCd 0 BadVer 0 BadNet 0 BadArea 0 BadDstAdr 0 BadAuType 0
BadAuth 0 BadNeigh 0 BadPckType 0 BadVirtLink 0
IntfDown 0 MySource 0 Legal 0
Hub GRE interface:
(HQ-1) [mynode] #show interface tunnel 1
Tunnel 1 is up line protocol is up
Description: Site-1-Primary
Internet address is 172.17.100.129 255.255.255.252
Source 172.17.100.1
Destination 172.17.100.3
Tunnel mtu is set to 1100
Tunnel is an IP GRE TUNNEL
Tunnel is Trusted
Inter Tunnel Flooding is enabled
OSPF is enabled on this interface
Tunnel keepalive is disabled
Keepalive type is Default
Tunnel keepalive interval is 10 seconds, retries 3
ICMP keepalive is disabled
Tunnel is down 0 times
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wei zhang
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