一、stub 末节区域
注意事项：四种特殊区域都需要所有端口配置相应属性
ABR自动产生一条三类LSA，宣告默认路由。
这里Area100为stub 末节区域
配置：
R1
interface Ethernet0/0
ip address 10.1.1.1 255.255.255.0
half-duplex
!
router ospf 10
log-adjacency-changes
area 100 stub
network 10.1.1.1 0.0.0.0 area 100
R2
interface Ethernet0/0
ip address 10.1.1.2 255.255.255.0
half-duplex
!
interface Ethernet0/1
ip address 20.1.1.2 255.255.255.0
half-duplex
!
router ospf 10
log-adjacency-changes
area 100 stub
network 10.1.1.2 0.0.0.0 area 100
network 20.1.1.2 0.0.0.0 area 0
R3
interface Ethernet0/1
ip address 20.1.1.3 255.255.255.0
half-duplex
!
router ospf 10
log-adjacency-changes
network 20.1.1.3 0.0.0.0 area 0
验证：
r1#p 20.1.1.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 20.1.1.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 260/334/388 ms
r1#sh ip route os
20.0.0.0/24 is subnetted, 1 subnets
O IA 20.1.1.0 [110/20] via 10.1.1.2, 00:26:09, Ethernet0/0
O*IA 0.0.0.0/0 [110/11] via 10.1.1.2, 00:26:09, Ethernet0/0
r1#sh ip os da
OSPF Router with ID (10.1.1.1) (Process ID 10)
Router Link States (Area 100)
Link ID ADV Router Age Seq# Checksum Link count
10.1.1.1 10.1.1.1 1684 0×80000002 0x008E68 1
10.1.1.2 10.1.1.2 1548 0×80000003 0x008D64 1
Net Link States (Area 100)
Link ID ADV Router Age Seq# Checksum
10.1.1.1 10.1.1.1 1683 0×80000001 0x00AF57
Summary Net Link States (Area 100)
Link ID ADV Router Age Seq# Checksum
0.0.0.0 10.1.1.2 1548 0×80000001 0x003CF3
20.1.1.0 10.1.1.2 1543 0×80000001 0x007A96
二、totally stub 完全末节区域
这里Area100为 totally stub ，也会自动发布一条（仅此一条）三类LSA
配置：
R1
interface Ethernet0/0
ip address 10.1.1.1 255.255.255.0
half-duplex
!
router ospf 10
log-adjacency-changes
area 100 stub no-summary
network 10.1.1.1 0.0.0.0 area 100
R2
interface Ethernet0/0
ip address 10.1.1.2 255.255.255.0
half-duplex
!
interface Ethernet0/1
ip address 20.1.1.2 255.255.255.0
half-duplex
!
router ospf 10
log-adjacency-changes
area 100 stub no-summary
network 10.1.1.2 0.0.0.0 area 100
network 20.1.1.2 0.0.0.0 area 0
验证：
r1#p 20.1.1.3
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 20.1.1.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 440/512/628 ms
r1#sh ip route os
O*IA 0.0.0.0/0 [110/11] via 10.1.1.2, 00:02:09, Ethernet0/0
这里和下面都可以看到，其他三类LSA没有了
r1#sh ip os da
OSPF Router with ID (10.1.1.1) (Process ID 10)
Router Link States (Area 100)
Link ID ADV Router Age Seq# Checksum Link count
10.1.1.1 10.1.1.1 381 0×80000003 0x008C69 1
10.1.1.2 10.1.1.2 279 0×80000004 0x008B65 1
Net Link States (Area 100)
Link ID ADV Router Age Seq# Checksum
10.1.1.1 10.1.1.1 381 0×80000002 0x00AD58
Summary Net Link States (Area 100)
Link ID ADV Router Age Seq# Checksum
0.0.0.0 10.1.1.2 173 0×80000003 0x0038F5
三、NSSA 次末节区域
配置完之后，我们发现没有到骨干区域0的默认路由，。其路由可以通过三类LSA学到
配置：
R1
interface Loopback0
ip address 192.168.1.1 255.255.255.255
!
interface Ethernet0/0
ip address 10.1.1.1 255.255.255.0
half-duplex
!
router ospf 20
log-adjacency-changes
area 100 nssa
redistribute rip subnets
network 10.1.1.1 0.0.0.0 area 100
!
router rip
version 2
network 192.168.1.0
R2
interface Ethernet0/0
ip address 10.1.1.2 255.255.255.0
half-duplex
!
interface Ethernet0/1
ip address 20.1.1.2 255.255.255.0
half-duplex
!
router ospf 20
log-adjacency-changes
area 100 nssa
network 10.1.1.2 0.0.0.0 area 100
network 20.1.1.2 0.0.0.0 area 0
R3
interface Loopback0
ip address 30.1.1.3 255.255.255.255
!
interface Ethernet0/1
ip address 20.1.1.3 255.255.255.0
half-duplex
!
router ospf 20
log-adjacency-changes
network 20.1.1.3 0.0.0.0 area 0
network 30.1.1.3 0.0.0.0 area 0
验证：
r1#sh ip os dat
OSPF Router with ID (192.168.1.1) (Process ID 20)
Router Link States (Area 100)
Link ID ADV Router Age Seq# Checksum Link count
20.1.1.2 20.1.1.2 490 0×80000003 0x003E95 1
192.168.1.1 192.168.1.1 489 0×80000003 0x004DE1 1
Net Link States (Area 100)
Link ID ADV Router Age Seq# Checksum
10.1.1.1 192.168.1.1 489 0×80000001 0x0038FF
Summary Net Link States (Area 100)
Link ID ADV Router Age Seq# Checksum
20.1.1.0 20.1.1.2 517 0×80000001 0x00A757
30.1.1.3 20.1.1.2 69 0×80000001 0x0011DF
Type-7 AS External Link States (Area 100)
Link ID ADV Router Age Seq# Checksum Tag
192.168.1.1 192.168.1.1 552 0×80000001 0x0009A9 0
r1#sh ip route os
20.0.0.0/24 is subnetted, 1 subnets
O IA 20.1.1.0 [110/20] via 10.1.1.2, 00:10:48, Ethernet0/0
30.0.0.0/32 is subnetted, 1 subnets
O IA 30.1.1.3 [110/21] via 10.1.1.2, 00:03:51, Ethernet0/0
下面我们将其添加默认路由，我们可以看到，其默认路由是通过7类LSA添加的。
这就是totally nssa没有3类LSA的原因，因为用的是
r2(config-router)#area 100 nssa default-information-originate
r1#sh ip os dat
OSPF Router with ID (192.168.1.1) (Process ID 20)
Router Link States (Area 100)
Link ID ADV Router Age Seq# Checksum Link count
20.1.1.2 20.1.1.2 706 0×80000003 0x003E95 1
192.168.1.1 192.168.1.1 705 0×80000003 0x004DE1 1
Net Link States (Area 100)
Link ID ADV Router Age Seq# Checksum
10.1.1.1 192.168.1.1 705 0×80000001 0x0038FF
Summary Net Link States (Area 100)
Link ID ADV Router Age Seq# Checksum
20.1.1.0 20.1.1.2 733 0×80000001 0x00A757
30.1.1.3 20.1.1.2 285 0×80000001 0x0011DF
Type-7 AS External Link States (Area 100)
Link ID ADV Router Age Seq# Checksum Tag
0.0.0.0 20.1.1.2 5 0×80000001 0x00E0AA 0
192.168.1.1 192.168.1.1 768 0×80000001 0x0009A9 0
r1#sh ip route os
20.0.0.0/24 is subnetted, 1 subnets
O IA 20.1.1.0 [110/20] via 10.1.1.2, 00:11:52, Ethernet0/0
30.0.0.0/32 is subnetted, 1 subnets
O IA 30.1.1.3 [110/21] via 10.1.1.2, 00:04:55, Ethernet0/0
O*N2 0.0.0.0/0 [110/1] via 10.1.1.2, 00:00:15, Ethernet0/0
一般来说，7类LSA由ASBR产生，我们看这里
r1#sh ip os da nssa-external
OSPF Router with ID (192.168.1.1) (Process ID 20)
Type-7 AS External Link States (Area 100)
Routing Bit Set on this LSA
LS age: 117
Options: (No TOS-capability, No Type 7/5 translation, DC)
LS Type: AS External Link
Link State ID: 0.0.0.0 (External Network Number )
Advertising Router: 20.1.1.2
LS Seq Number: 80000001
Checksum: 0xE0AA
Length: 36
Network Mask: /0
Metric Type: 2 (Larger than any link state path)
TOS: 0
Metric: 1
Forward Address: 10.1.1.2
External Route Tag: 0
四、totally NSSA 完全次末节区域
会自动产生默认路由
r1(config-router)#area 100 nssa no-summary
r2(config-router)#are 100 nssa no-s
r1#sh ip route os
O*IA 0.0.0.0/0 [110/11] via 10.1.1.2, 00:00:10, Ethernet0/0
r1#sh ip os dat
OSPF Router with ID (192.168.1.1) (Process ID 20)
Router Link States (Area 20)
Link ID ADV Router Age Seq# Checksum Link count
192.168.1.1 192.168.1.1 114 0×80000001 0x0069FA 0
Type-7 AS External Link States (Area 20)
Link ID ADV Router Age Seq# Checksum Tag
192.168.1.1 192.168.1.1 113 0×80000001 0x00734C 0
Router Link States (Area 100)
Link ID ADV Router Age Seq# Checksum Link count
20.1.1.2 20.1.1.2 1708 0×80000003 0x003E95 1
192.168.1.1 192.168.1.1 1707 0×80000003 0x004DE1 1
Net Link States (Area 100)
Link ID ADV Router Age Seq# Checksum
10.1.1.1 192.168.1.1 1707 0×80000001 0x0038FF
Summary Net Link States (Area 100)
Link ID ADV Router Age Seq# Checksum
0.0.0.0 20.1.1.2 78 0×80000001 0x0069B4
Type-7 AS External Link States (Area 100)
Link ID ADV Router Age Seq# Checksum Tag
0.0.0.0 20.1.1.2 1008 0×80000001 0x00E0AA 0
192.168.1.1 192.168.1.1 1770 0×80000001 0x0009A9 0
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