Protocols/BGP_OSPF_MPLS_VPN
[MPLS] OSPF Super Backbone Area (2)
양된백성
2021. 6. 23. 17:24
<목적>
1. Super Backbone Area와 동시에 Area 0는 없애기. (Area0는 2개 이상은 Area가 있는 경우 반드시 있어야 함)
2. Area 0가 없는데 OSPF 정상작동 가능한가?
<조건>
R1 - R4 는 Area 1, R2 - R5 는 Area 2, R3 - R6 은 Area 3
R1, R2, R3은 Super Backbone Area에 속한 라우터
<R4>
R4는 Area 1에 속해 있으며, 1.1.5.5와 1.1.6.6으로 Ping 가능
R4는 1.1.5.5, 1.1.6.6 모두 LSA type 3으로 광고받고 있음
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
|
R4#show ip ospf database
OSPF Router with ID (1.1.4.4) (Process ID 1)
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
1.1.1.1 1.1.1.1 553 0x80000001 0x00DC1D 1
1.1.4.4 1.1.4.4 552 0x80000003 0x00C40A 2
Net Link States (Area 1)
Link ID ADV Router Age Seq# Checksum
1.1.14.4 1.1.4.4 552 0x80000001 0x000C02
Summary Net Link States (Area 1)
Link ID ADV Router Age Seq# Checksum
1.1.5.5 1.1.1.1 520 0x80000001 0x00CFD1
1.1.6.6 1.1.1.1 491 0x80000001 0x00BAE4
1.1.25.0 1.1.1.1 553 0x80000001 0x00C0DB
1.1.36.0 1.1.1.1 553 0x80000001 0x00474A
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
4.4.4.4 1.1.4.4 1026 0x8000000C 0x00D3A7 0
R4#
R4#ping 1.1.5.5
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.5.5, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/2 ms
R4#ping 1.1.6.6
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.6.6, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/2 ms
R4#
|
cs |
각 라우터 모두 Area1, 2, 3에 속해있다.
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
|
R1#show run | b router ospf
router ospf 1 vrf company1
router-id 1.1.1.1
redistribute bgp 1 subnets
network 1.1.14.1 0.0.0.0 area 1
R2#show run | b router ospf
router ospf 1 vrf company1
router-id 1.1.2.2
redistribute bgp 1 subnets
network 1.1.25.2 0.0.0.0 area 2
R3#show run | b router ospf
router ospf 1 vrf company1
router-id 1.1.3.3
redistribute bgp 1 subnets
network 1.1.36.3 0.0.0.0 area 3
R4#show run | b router ospf
router ospf 1
router-id 1.1.4.4
redistribute connected subnets
network 1.1.4.4 0.0.0.0 area 1
network 1.1.14.4 0.0.0.0 area 1
R5#show run | b router ospf
router ospf 1
router-id 1.1.5.5
network 1.1.5.5 0.0.0.0 area 2
network 1.1.25.5 0.0.0.0 area 2
R6#show run | b router ospf
router ospf 1
router-id 1.1.6.6
network 1.1.6.6 0.0.0.0 area 3
network 1.1.36.6 0.0.0.0 area 3
|
cs |
결론,
Area 0가 없는데 OSPF 정상작동 가능한가? Super Backbone Area를 사용할 경우 Area 0가 없어도 Super Backbone Area가 Backbone Area를 대체하여 정상작동 가능하다.