（1）在MSR36上查看SR88邻居状态如下：
===============display
ospf peer===============
OSPF Process 1 with Router ID XX.4.250.130
Neighbor Brief Information
Area:
0.0.0.11
Router
ID
Address Pri Dead-Time
State
Interface
XX.230.255.XX
XX.4.250.133 1
40 Init/ -
GE0/1
//这里显示故障（主）SR88的接口地址是XX.4.250.133
XX.4.255.177
XX.4.248.129 1
31 Full/
- Vlan30
在SR88上查看MSR36状态如下：
XX.4.250.130
XX.4.250.130 1
33 ExStart/ -
GE7/0/3.2071
//这里显示故障（主）SR88的出接口是GE7/0/3.2071，地址是XX.4.250.129，与上面的地址不符。
Interface: XX.4.250.129
(GigabitEthernet7/0/3.2071) --> XX.4.250.130
Cost:
1 State: P-2-P
Type: PTP MTU: 1500
Timers:
Hello XX, Dead 40, Poll 40, Retransmit 5, Transmit Delay 1
FRR backup:
Enabled
Enabled by
network configuration
interface
GigabitEthernet7/0/3.2071
description To_****
ip address XX.4.250.129
255.255.255.252
ospf network-type
p2p
vlan-type dot1q
vid 2071
而这个XX.4.250.133是故障88上的一个地址，这个地址与另一个网点的迈普设备能正常建立ospf邻居。
且现场将MSR36的G0/1口人为shutdown，再undo
shutdown，后，在MSR上查看邻居peer，发现故障88的接口地址又变为XX.4.250.121：
（2）检查两端的ospf配置，没有什么异常，两端ospf的hello、dead时间都是默认值，一致。
（3）MSR36的日志里面提示ospf状态变为down：
Line 147XX:
%@14677%Jan 19 02:06:30:386 2023 OSPF/6/OSPF_LAST_NBR_DOWN: OSPF 1 Last neighbor
down event: Router ID: XX.230.255.XX Local address: XX.4.250.130 Remote
address: XX.4.250.133 Reason: Ospf_ifachange.
Line 147XX:
%@14677%Jan 19 02:06:30:386 2023 OSPF/6/OSPF_LAST_NBR_DOWN:
OSPF 1 Last neighbor down event: Router ID: XX.230.255.XX Local address: XX.4.250.130
Remote address: XX.4.250.133 Reason: Ospf_ifachange.
Line 14711:
%@14678%Jan 19 02:06:30:389 2023 OSPF/5/OSPF_NBR_CHG:
OSPF 1 Neighbor XX.4.250.133(GigabitEthernet0/1) changed from INIT to DOWN.
Line 14711:
%@14678%Jan 19 02:06:30:389 2023 OSPF/5/OSPF_NBR_CHG:
OSPF 1 Neighbor XX.4.250.133(GigabitEthernet0/1) changed from INIT to DOWN.
SR88的日志里面提示：
Line 27553: %Jan
19 XX:07:09:268 2023 QHRC-A-NT-WAN-WRT01 OSPF/6/OSPF_LAST_NBR_DOWN: OSPF XX0
Last neighbor down event: Router ID: XX.4.250.130 Local address: XX.4.250.129
Remote address: XX.4.250.130 Reason: DeadInterval
timer expired.
Line 27554: %Jan
19 XX:07:09:269 2023 QHRC-A-NT-WAN-WRT01 OSPF/5/OSPF_NBR_CHG: OSPF XX0 Neighbor
XX.4.250.130(GigabitEthernet7/0/3.2071) changed from EXSTART to DOWN.
查看两个设备有路由，且在MSR36上pingSR88，是通的，且不丢包：
Line 3096: %Jan
18 08:16:26:063 2023 SHELL/6/SHELL_CMD:
-Line=vty0-IPAddr=XX.4.250.129-User=admin; Command is ping -s 1800 -a XX.4.250.130 XX.4.250.129
Line 3097: %Jan
18 08:16:27:084 2023 PING/6/PING_STATISTICS:
Ping statistics for XX.4.250.129: 5 packets transmitted, 5 packets received,
0.0% packet loss, round-trip min/avg/max/std-dev = 31.964/37.473/48.604/6.475
ms.
（4）在MSR36这一端收集debug
ospf event，显示如下：
怀疑是对端88的地址有问题
*Mar 19
02:11:02:305 2023 OSPF/7/DEBUG:
OSPF: Recv
packet from unknown non-shamlink/vlink nbr XX.4.250.129.
*Mar 19
02:11:02:426 2023 OSPF/7/DEBUG:
OSPF: Recv
packet from unknown non-shamlink/vlink nbr XX.4.254.XX9.
*Mar 19
02:11:02:427 2023 OSPF/7/DEBUG:
OSPF: Recv
packet from unknown non-shamlink/vlink nbr XX.4.254.113.
*Mar 19
02:11:02:427 2023 OSPF/7/DEBUG:
OSPF: Recv
packet from unknown non-shamlink/vlink nbr XX.4.254.237.
*Mar 19
02:11:02:428 2023 OSPF/7/DEBUG:
OSPF: Recv
packet from unknown non-shamlink/vlink nbr XX.4.250.121.
*Mar 19
02:11:02:429 2023 OSPF/7/DEBUG:
OSPF: Recv
packet from unknown non-shamlink/vlink nbr XX.4.250.125.
