1. To determine how OSPF LSA Type 4 & 5 can be formed. This can simply done via redistribution.
2. Configure a multiple areas OSPF.
3. How to check OSPF Type 4 & Type 5 LSA.
Here is my GNS3 topology for this laboratory,
So this is how my configurations look like on the 4 routers:
MANILA Router:
R1#config t
Enter configuration commands, one per line. End with CNTL/Z.
R1(config)#hostname MANILA
MANILA(config)#int s2/0
MANILA(config-if)#ip add 192.168.12.1 255.255.255.0
MANILA(config-if)#no shut
MANILA(config-if)#exit
MANILA(config)#int lo1
MANILA(config-if)#ip add 10.10.10.1 255.255.255.0
MANILA(config-if)#exit
MANILA(config)#router ospf 1
MANILA(config-router)#network 10.10.10.0 0.0.0.255 area 1
MANILA(config-router)#network 192.168.12.0 0.0.0.255 area 1
MANILA(config-router)#^Z
MELBOURNE Router:
R2#config t
Enter configuration commands, one per line. End with CNTL/Z.
R2(config)#hostname MELBOURNE
MELBOURNE(config)#int s2/0
MELBOURNE(config-if)#ip add 192.168.12.2 255.255.255.0
MELBOURNE(config-if)#no shut
MELBOURNE(config-if)#exit
MELBOURNE(config)#int s2/1
MELBOURNE(config-if)#ip add 192.168.23.2 255.255.255.0
MELBOURNE(config-if)#no shut
MELBOURNE(config-if)#^Z
MELBOURNE(config)#int lo2
MELBOURNE(config-if)#ip add 20.20.20.1 255.255.255.0
MELBOURNE(config-if)#exit
MELBOURNE(config)#router ospf 1
MELBOURNE(config-router)#network 192.168.12.0 0.0.0.255 area 1
MELBOURNE(config-router)#network 192.168.23.0 0.0.0.255 area 0
MELBOURNE(config-router)#network 20.20.20.0 0.0.0.255 area 0
MELBOURNE(config-router)#^Z
SINGAPORE Router:
R3#config t
Enter configuration commands, one per line. End with CNTL/Z.
R3(config)#hostname SINGAPORE
SINGAPORE(config)#int s2/0
SINGAPORE(config-if)#ip add 192.168.23.3 255.255.255.0
SINGAPORE(config-if)#no shut
SINGAPORE(config-if)#int lo3
SINGAPORE(config-if)#ip add 30.30.30.1 255.255.255.0
SINGAPORE(config-if)#exit
SINGAPORE(config)#int s2/2
SINGAPORE(config-if)#ip address 192.168.34.3 255.255.255.0
SINGAPORE(config-if)#no shut
SINGAPORE(config)#router ospf 1
SINGAPORE(config-router)#network 192.168.23.0 0.0.0.255 area 0
SINGAPORE(config-router)#network 192.168.34.0 0.0.0.255 area 2
SINGAPORE(config-router)#network 30.30.30.0 0.0.0.255 area 0
SINGAPORE(config-router)#exit
HONGKONG Router:
R4#config t
Enter configuration commands, one per line. End with CNTL/Z.
R4(config)#hostname HONGKONG
HONGKONG(config)#int s2/2
HONGKONG(config-if)#ip address 192.168.34.4 255.255.255.0
HONGKONG(config-if)#no shut
HONGKONG(config-if)#int lo4
HONGKONG(config-if)#ip add 40.40.40.1 255.255.255.0
HONGKONG(config-if)#exit
HONGKONG(config)#router ospf 1
HONGKONG(config-router)#network 192.168.34.0 0.0.0.255 area 2
HONGKONG(config-router)#redistribute connected subnets
HONGKONG(config-router)#^Z
VERIFICATIONS:
A. OSPF Neighbor status
Neighbor ID Pri State Dead Time Address Interface
20.20.20.1 0 FULL/ – 00:00:35 192.168.12.2 Serial2/0
MANILA#
30.30.30.1 0 FULL/ – 00:00:37 192.168.23.3 Serial2/1
10.10.10.1 0 FULL/ – 00:00:31 192.168.12.1 Serial2/0
MELBOURNE#
20.20.20.1 0 FULL/ – 00:00:32 192.168.23.2 Serial2/1
40.40.40.1 0 FULL/ – 00:00:36 192.168.34.4 Serial2/2
SINGAPORE#
30.30.30.1 0 FULL/ – 00:00:31 192.168.34.3 Serial2/2
HONGKONG#
B. Let’s check the OSPF database whether Type 4 & Type 5 LSA were keep. I will check further in MANILA router since we have a routes redistributed in HONGKONG router.
OSPF Router with ID (10.10.10.1) (Process ID 1)
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
10.10.10.1 10.10.10.1 1871 0x80000003 0x009377 3
20.20.20.1 20.20.20.1 1835 0x80000002 0x00DE3D 2
Summary Net Link States (Area 1)
Link ID ADV Router Age Seq# Checksum
20.20.20.1 20.20.20.1 1825 0x80000001 0x00CEF2
30.30.30.1 20.20.20.1 1477 0x80000001 0x00E77B
192.168.23.0 20.20.20.1 1477 0x80000001 0x0074CA
192.168.34.0 20.20.20.1 1477 0x80000001 0x007D76
Summary ASB Link States (Area 1)
Link ID ADV Router Age Seq# Checksum
40.40.40.1 20.20.20.1 1477 0x80000001 0x00E81C
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag40.40.40.0 40.40.40.1 1398 0x80000001 0x007836 0
MANILA#
Summary Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.10.10.1 20.20.20.1 213 0x80000002 0x00B8E5
192.168.12.0 20.20.20.1 213 0x80000002 0x00EB5D
192.168.34.0 30.30.30.1 104 0x80000002 0x00080D
Summary ASB Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
40.40.40.1 30.30.30.1 104 0x80000002 0x0073B2
Router Link States (Area 1)
Link ID ADV Router Age Seq# Checksum Link count
10.10.10.1 10.10.10.1 238 0x80000004 0x009178 3
20.20.20.1 20.20.20.1 213 0x80000003 0x00DC3E 2
Summary Net Link States (Area 1)
Link ID ADV Router Age Seq# Checksum
20.20.20.1 20.20.20.1 213 0x80000002 0x00CCF3
30.30.30.1 20.20.20.1 1803 0x80000001 0x00E77B
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
40.40.40.0 40.40.40.1 1813 0x80000001 0x007836 0
MELBOURNE#
OSPF Router with ID (30.30.30.1) (Process ID 1)
Router Link States (Area 0)
Link ID ADV Router Age Seq# Checksum Link count
20.20.20.1 20.20.20.1 1156 0x80000004 0x002059 3
30.30.30.1 30.30.30.1 41 0x80000009 0x006CCA 3
Summary Net Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
10.10.10.1 20.20.20.1 400 0x80000002 0x00B8E5
192.168.12.0 20.20.20.1 400 0x80000002 0x00EB5D
192.168.34.0 30.30.30.1 290 0x80000002 0x00080D
Summary ASB Link States (Area 0)
Link ID ADV Router Age Seq# Checksum
40.40.40.1 30.30.30.1 290 0x80000002 0x0073B2
Router Link States (Area 2)
Link ID ADV Router Age Seq# Checksum Link count
30.30.30.1 30.30.30.1 290 0x80000006 0x004C08 2
40.40.40.1 40.40.40.1 160 0x80000003 0x00181F 2
Summary Net Link States (Area 2)
Link ID ADV Router Age Seq# Checksum
10.10.10.1 30.30.30.1 41 0x80000002 0x004AF5
20.20.20.1 30.30.30.1 41 0x80000002 0x005E04
30.30.30.1 30.30.30.1 290 0x80000003 0x007013
192.168.12.0 30.30.30.1 41 0x80000002 0x007D6D
192.168.23.0 30.30.30.1 41 0x80000002 0x00819E
Type-5 AS External Link States
Link ID ADV Router Age Seq# Checksum Tag
40.40.40.0 40.40.40.1 1911 0x80000001 0x007836 0
SINGAPORE#
C. Now, let’s check the routing table of the three routers.
Codes: L – local, C – connected, S – static, R – RIP, M – mobile, B – BGP
D – EIGRP, EX – EIGRP external, O – OSPF, IA – OSPF inter area
N1 – OSPF NSSA external type 1, N2 – OSPF NSSA external type 2
E1 – OSPF external type 1, E2 – OSPF external type 2
i – IS-IS, su – IS-IS summary, L1 – IS-IS level-1, L2 – IS-IS level-2
ia – IS-IS inter area, * – candidate default, U – per-user static route
o – ODR, P – periodic downloaded static route, H – NHRP, l – LISP
+ – replicated route, % – next hop override
Gateway of last resort is not set
20.0.0.0/32 is subnetted, 1 subnets
O IA 20.20.20.1 [110/65] via 192.168.12.2, 00:41:02, Serial2/0
30.0.0.0/32 is subnetted, 1 subnets
O IA 30.30.30.1 [110/129] via 192.168.12.2, 00:35:14, Serial2/0
40.0.0.0/24 is subnetted, 1 subnets
O E2 40.40.40.0 [110/20] via 192.168.12.2, 00:33:53, Serial2/0
O IA 192.168.23.0/24 [110/128] via 192.168.12.2, 00:35:14, Serial2/0
O IA 192.168.34.0/24 [110/192] via 192.168.12.2, 00:35:14, Serial2/0
MANILA#
>>> as seen above, we have both the TYPE LSA routes ( O E2) and the LSA Type 3 (SUMMARY LSA) designated by O IA.
>>> The Inter-Area Routes ( O IA) were generated by the MELBOURNE router as the ABR to Area 1.
Codes: L – local, C – connected, S – static, R – RIP, M – mobile, B – BGP
D – EIGRP, EX – EIGRP external, O – OSPF, IA – OSPF inter area
N1 – OSPF NSSA external type 1, N2 – OSPF NSSA external type 2
E1 – OSPF external type 1, E2 – OSPF external type 2
i – IS-IS, su – IS-IS summary, L1 – IS-IS level-1, L2 – IS-IS level-2
ia – IS-IS inter area, * – candidate default, U – per-user static route
o – ODR, P – periodic downloaded static route, H – NHRP, l – LISP
+ – replicated route, % – next hop override
Gateway of last resort is not set
10.0.0.0/32 is subnetted, 1 subnets
O 10.10.10.1 [110/65] via 192.168.12.1, 00:45:50, Serial2/0
30.0.0.0/32 is subnetted, 1 subnets
O 30.30.30.1 [110/65] via 192.168.23.3, 00:39:52, Serial2/1
40.0.0.0/24 is subnetted, 1 subnets
O E2 40.40.40.0 [110/20] via 192.168.23.3, 00:38:31, Serial2/1
O IA 192.168.34.0/24 [110/128] via 192.168.23.3, 00:39:52, Serial2/1
MELBOURNE#
Codes: L – local, C – connected, S – static, R – RIP, M – mobile, B – BGP
D – EIGRP, EX – EIGRP external, O – OSPF, IA – OSPF inter area
N1 – OSPF NSSA external type 1, N2 – OSPF NSSA external type 2
E1 – OSPF external type 1, E2 – OSPF external type 2
i – IS-IS, su – IS-IS summary, L1 – IS-IS level-1, L2 – IS-IS level-2
ia – IS-IS inter area, * – candidate default, U – per-user static route
o – ODR, P – periodic downloaded static route, H – NHRP, l – LISP
+ – replicated route, % – next hop override
Gateway of last resort is not set
10.0.0.0/32 is subnetted, 1 subnets
O IA 10.10.10.1 [110/129] via 192.168.23.2, 00:28:17, Serial2/1
20.0.0.0/32 is subnetted, 1 subnets
O 20.20.20.1 [110/65] via 192.168.23.2, 00:28:17, Serial2/1
40.0.0.0/24 is subnetted, 1 subnets
O E2 40.40.40.0 [110/20] via 192.168.34.4, 00:40:57, Serial2/2
O IA 192.168.12.0/24 [110/128] via 192.168.23.2, 00:28:17, Serial2/1
SINGAPORE#
HONGKONG#show ip route ospf
Codes: L – local, C – connected, S – static, R – RIP, M – mobile, B – BGP
D – EIGRP, EX – EIGRP external, O – OSPF, IA – OSPF inter area
N1 – OSPF NSSA external type 1, N2 – OSPF NSSA external type 2
E1 – OSPF external type 1, E2 – OSPF external type 2
i – IS-IS, su – IS-IS summary, L1 – IS-IS level-1, L2 – IS-IS level-2
ia – IS-IS inter area, * – candidate default, U – per-user static route
o – ODR, P – periodic downloaded static route, H – NHRP, l – LISP
+ – replicated route, % – next hop override
Gateway of last resort is not set
10.0.0.0/32 is subnetted, 1 subnets
O IA 10.10.10.1 [110/193] via 192.168.34.3, 00:44:16, Serial2/2
20.0.0.0/32 is subnetted, 1 subnets
O IA 20.20.20.1 [110/129] via 192.168.34.3, 00:44:16, Serial2/2
30.0.0.0/32 is subnetted, 1 subnets
O IA 30.30.30.1 [110/65] via 192.168.34.3, 00:47:06, Serial2/2
O IA 192.168.12.0/24 [110/192] via 192.168.34.3, 00:44:16, Serial2/2
O IA 192.168.23.0/24 [110/128] via 192.168.34.3, 00:44:16, Serial2/2
HONGKONG#
D. Final testing is the connectivity. I will just do a simple ping and traceroutes between MANILA and HONGKONG and THAT’S IT! If it works then, I’m done with this lab.
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 40.40.40.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 60/67/80 ms
MANILA#
MANILA#
MANILA#MANILA#traceroute 40.40.40.1
Type escape sequence to abort.
Tracing the route to 40.40.40.1
VRF info: (vrf in name/id, vrf out name/id)
1 192.168.12.2 56 msec 48 msec 48 msec
2 192.168.23.3 56 msec 52 msec 56 msec
3 192.168.34.4 76 msec 80 msec 72 msec
MANILA#
NETWORK LESSON 
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