Based on the analysis of the preceding possible causes, it can be concluded:
1.
The configurations of the devices are normal.
2.
The LSA whose FA field meets the condition of route calculation.
<RouterA>
ping 10.1.3.1
PING 10.1.3.1: 56 data bytes, press CTRL_C to break
Reply from 10.1.3.1: bytes=56 Sequence=1 ttl=255 time=1 ms
Reply from 10.1.3.1: bytes=56 Sequence=2 ttl=255 time=1 ms
Reply from 10.1.3.1: bytes=56 Sequence=3 ttl=255 time=1 ms
Reply from 10.1.3.1: bytes=56 Sequence=4 ttl=255 time=1 ms
Reply from 10.1.3.1: bytes=56 Sequence=5 ttl=255 time=1 ms
--- 10.1.3.1 ping statistics ---
5 packet(s) transmitted
5 packet(s) received
0.00% packet loss
round-trip min/avg/max = 1/1/1 ms
<RouterA>
display ip routing-table 10.1.3.1
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Routing Table : Public
Summary Count : 2
Destination/Mask Proto Pre Cost Flags NextHop Interface
10.1.3.1/32 O_ASE 150 1 D 10.1.2.45
GigabitEthernet1/0/0
O_ASE 150 1 D 10.1.2.49
GigabitEthernet2/0/0
<RouterA>
ping 10.1.2.26
Reply from 10.1.2.26: bytes=56 Sequence=1 ttl=254 time=1 ms
Reply from 10.1.2.26: bytes=56 Sequence=2 ttl=254 time=1 ms
0.00% packet loss
round-trip min/avg/max = 1/1/1 ms
<RouterA>
display ip routing-table 10.1.2.26
10.1.2.24/30 OSPF 10 101 D 10.1.2.45
GigabitEthernet1/0/0
OSPF 10 101 D 10.1.2.49 GigabitEthernet2/0/0
3.
On this network, the costs of LSAs are 1. Compare the cost of the route to the ASBR and
the cost of the route to the FA.
For Type 2 ASE LSAs, OSPF equal-cost routes can be generated when the following
conditions are met:
a.
The costs of LSAs are the same.
b.
The cost of the route to the ASBR is the same as the cost of the route to the FA.
On the network, the cost of the route to the FA is 101.
l
For the LSA with the FA field 0.0.0.0, the cost of the route to ASBR at 10.1.3.1 is 1.
l
For the LSA with an FA field other than 0.0.0.0, the cost of the route to the FA at
10.1.2.26 is 101.
The LSA with the FA field being set is not calculated because the priority of the LSA is
lower. As a result, equal-cost routes cannot be formed.
Procedure
Step 1
To form equal-cost routes on the network, do as follows:
Huawei AR2200-S Series Enterprise Routers
Troubleshooting
7 IP Forwarding and Routing
Issue 01 (2012-01-06)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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