Lab50. OSPF Not So Stubby Area

ospf-standar-areaObjective
Mempelajari pengaruh NSSA area pada OSPF

Metode Lab

  • Masih menggunakan topologi dan konfigurasi sebelumnya
  • Konfigurasikan NSSA pada semua router OSPF Area 1
  • Konfigurasikan Default Information originate di router ABR mendistribusikan default route ke semua router dalam area NSSA

 

Verifikasi Lab
Periksa routing tabel pada router RM-R3

  • Seperti ini area tapi masih bisa goyang
  • Kalau pada stub dan totally stub area, maka External Route benar2 tidak diterima ataupun dikirimkan, nah bila diinginkan pada area stub masih bisa mengirim External Route maka solusinya menggunakan NSSA
  • Namun External route ini tidak sebagai LSA Type 5, melainkan dalam bentuk LSA Type 7, karena memang LSA type 3,4,5 RM-R2 dibatasi pada stub area, jadi alternatifnya diakali menggunakan LSA Type 7
  • Dan bila diinginkan Internal Route OSPF dari area lain masih bisa diterima, maka solusinya juga menggunakan LSA Tipe 7
  • Dan bila diinginkan Internal Route OSPF dari area lain masih bisa diterima, maka solusinya juga menggunakan NSSA
  • Dikonfigurasikan pada semua router pada area stub

Tambahkan dulu Routing External RIP yang diredistribute ke OSPF di router RM-R3 are stub

RM-R3(config)#int lo1
RM-R3(config-if)#ip addr 33.33.33.1 255.255.255.255
RM-R3(config-if)#int lo2
RM-R3(config-if)#ip addr 33.33.33.2 255.255.255.255    
RM-R3(config-if)#int lo3
RM-R3(config-if)#ip addr 33.33.33.3 255.255.255.255
RM-R3(config-if)#router rip
RM-R3(config-router)#vers 2
RM-R3(config-router)#no auto-summary
RM-R3(config-router)#network 33.0.0.0
RM-R3(config-router)#router ospf 3
RM-R3(config-router)#redistribute rip subnets

Selanjutnya konfigurasikan NSSA

RM-R2(config)#router ospf 2
RM-R2(config-router)#area 1 nssa
OSPF: Area is configured as stub area already
RM-R2(config-router)#no area 1 stub  no-summary
RM-R2(config-router)#area 1 nssa
OSPF: Area is configured as stub area already
RM-R2(config-router)#no area 1 stub
RM-R2(config-router)#area 1 nssa
RM-R3(config)#router os 3
RM-R3(config-router)#no area 1 stub
RM-R3(config-router)#area 1 nssa
RM-R3(config-router)#
*Mar  1 01:39:56.223: %OSPF-5-ADJCHG: Process 3, Nbr 2.2.2.2 on Serial0/0 from LOADING to FULL, Loading Done

Cek lagi routing tabelnya

RM-R3(config-router)#do sh ip route
Codes: 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

Gateway of last resort is not set

     1.0.0.0/32 is subnetted, 1 subnets
O IA    1.1.1.1 [110/75] via 23.23.23.2, 00:00:40, Serial0/0
     2.0.0.0/32 is subnetted, 1 subnets
O       2.2.2.2 [110/65] via 23.23.23.2, 00:00:40, Serial0/0
     33.0.0.0/32 is subnetted, 3 subnets
C       33.33.33.1 is directly connected, Loopback1
C       33.33.33.3 is directly connected, Loopback3
C       33.33.33.2 is directly connected, Loopback2
     3.0.0.0/32 is subnetted, 1 subnets
C       3.3.3.3 is directly connected, Loopback0
     23.0.0.0/24 is subnetted, 1 subnets
C       23.23.23.0 is directly connected, Serial0/0
     10.0.0.0/32 is subnetted, 3 subnets
O IA    10.10.10.2 [110/75] via 23.23.23.2, 00:00:51, Serial0/0
O IA    10.10.10.3 [110/75] via 23.23.23.2, 00:00:51, Serial0/0
O IA    10.10.10.1 [110/75] via 23.23.23.2, 00:00:51, Serial0/0
     12.0.0.0/24 is subnetted, 1 subnets
O IA    12.12.12.0 [110/74] via 23.23.23.2, 00:00:51, Serial0/0
RM-R3(config-router)#

Akhirnya Internal Area dari OSPF area 100 bisa diterima dengan baik di stub router RM-R3

RM-R1(config-router)#do sh ip route
Codes: 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

Gateway of last resort is not set

     1.0.0.0/32 is subnetted, 1 subnets
C       1.1.1.1 is directly connected, Loopback0
     2.0.0.0/32 is subnetted, 1 subnets
O IA    2.2.2.2 [110/11] via 12.12.12.2, 00:03:54, FastEthernet0/0
     33.0.0.0/32 is subnetted, 3 subnets
O E2    33.33.33.1 [110/20] via 12.12.12.2, 00:02:46, FastEthernet0/0
O E2    33.33.33.3 [110/20] via 12.12.12.2, 00:02:46, FastEthernet0/0
O E2    33.33.33.2 [110/20] via 12.12.12.2, 00:02:46, FastEthernet0/0
     3.0.0.0/32 is subnetted, 1 subnets
O IA    3.3.3.3 [110/75] via 12.12.12.2, 00:02:55, FastEthernet0/0
     23.0.0.0/24 is subnetted, 1 subnets
O IA    23.23.23.0 [110/74] via 12.12.12.2, 00:03:59, FastEthernet0/0
     10.0.0.0/32 is subnetted, 7 subnets
          
RM-R1(config-router)#

Dan External Route RIP dari RM-R3 sudah bisa diterima di router RM-R1
Namun demikian bila diperhatikan belum ada default route nya, sehingga RM-R3 belum bisa ping ke IP 10.10.10.4 – 10.10.10.7 yang merupakan network EIGRP di RM-R1 yang diredistribute ke OSPF

RM-R3(config)#do ping 10.10.10.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.4, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
RM-R3(config)#

maka kita perlu menambahkan konfigurasi berikut cukup pada router ABR nya saja yakni dalam hal ini router RM-R2

RM-R2(config)#router os 2
RM-R2(config-router)#area 1 nssa default-information-originate

Selanjutnya cek lagi pada routing tabelnya pada RM-R3

RM-R3(config)#do sh ip route
Codes: 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

Gateway of last resort is 23.23.23.2 to network 0.0.0.0

     1.0.0.0/32 is subnetted, 1 subnets
O IA    1.1.1.1 [110/75] via 23.23.23.2, 00:08:20, Serial0/0
     2.0.0.0/32 is subnetted, 1 subnets
O       2.2.2.2 [110/65] via 23.23.23.2, 00:08:20, Serial0/0
     33.0.0.0/32 is subnetted, 3 subnets
C       33.33.33.1 is directly connected, Loopback1
C       33.33.33.3 is directly connected, Loopback3
C       33.33.33.2 is directly connected, Loopback2
     3.0.0.0/32 is subnetted, 1 subnets
C       3.3.3.3 is directly connected, Loopback0
     23.0.0.0/24 is subnetted, 1 subnets
C       23.23.23.0 is directly connected, Serial0/0
     10.0.0.0/32 is subnetted, 3 subnets
O IA    10.10.10.2 [110/75] via 23.23.23.2, 00:08:28, Serial0/0
O IA    10.10.10.3 [110/75] via 23.23.23.2, 00:08:28, Serial0/0
O IA    10.10.10.1 [110/75] via 23.23.23.2, 00:08:28, Serial0/0
     12.0.0.0/24 is subnetted, 1 subnets
O IA    12.12.12.0 [110/74] via 23.23.23.2, 00:08:28, Serial0/0
O*N2 0.0.0.0/0 [110/1] via 23.23.23.2, 00:00:56, Serial0/0
RM-R3(config)#do sh ip ospf database

            OSPF Router with ID (3.3.3.3) (Process ID 3)

                Router Link States (Area 1)

Link ID         ADV Router      Age         Seq#       Checksum Link count
2.2.2.2         2.2.2.2         547         0x8000000C 0x00705E 3
3.3.3.3         3.3.3.3         380         0x80000009 0x0011B8 3

                Summary Net Link States (Area 1)

Link ID         ADV Router      Age         Seq#       Checksum
1.1.1.1         2.2.2.2         608         0x80000003 0x002FEE
10.10.10.1      2.2.2.2         608         0x80000003 0x00E919
10.10.10.2      2.2.2.2         608         0x80000003 0x00DF22
10.10.10.3      2.2.2.2         608         0x80000003 0x00D52B
12.12.12.0      2.2.2.2         608         0x80000003 0x00A15D

                Type-7 AS External Link States (Area 1)

Link ID         ADV Router      Age         Seq#       Checksum Tag
0.0.0.0         2.2.2.2         84          0x80000001 0x00D0D8 0
33.33.33.1      3.3.3.3         541         0x80000001 0x00DC3D 0
33.33.33.2      3.3.3.3         541         0x80000001 0x00D246 0
33.33.33.3      3.3.3.3         546         0x80000001 0x00C84F 0
RM-R3(config)#

default route (0.0.0.0/0) sudah muncul sekarang dan kita lakukan tes ping lagi

RM-R3(config)#do ping 10.10.10.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 132/377/596 ms
RM-R3(config)#do ping 10.10.10.6

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.6, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/156/284 ms
RM-R3(config)#do ping 10.10.10.5

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.5, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 60/163/272 ms
RM-R3(config)#do ping 10.10.10.7

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.7, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 60/198/352 ms
RM-R3(config)#

Kalau kemudian diinginkan internal route OSPF area lain tidak ditampilkan dalam database, namun masih bisa tetap mengirimkan External Route RIP nya, maka tambahkan no-summary pada router ABR RM-R2

RM-R2(config-router)#router os 2
RM-R2(config-router)#area 1 nssa no-summary

Maka pada RM-R3 sudah tidak lagi terdapat routing inter area dan digantikan dengan default route saja

RM-R3(config)#do sh ip route
Codes: 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

Gateway of last resort is 23.23.23.2 to network 0.0.0.0

     2.0.0.0/32 is subnetted, 1 subnets
O       2.2.2.2 [110/65] via 23.23.23.2, 00:13:26, Serial0/0
     33.0.0.0/32 is subnetted, 3 subnets
C       33.33.33.1 is directly connected, Loopback1
C       33.33.33.3 is directly connected, Loopback3
C       33.33.33.2 is directly connected, Loopback2
     3.0.0.0/32 is subnetted, 1 subnets
C       3.3.3.3 is directly connected, Loopback0
     23.0.0.0/24 is subnetted, 1 subnets
C       23.23.23.0 is directly connected, Serial0/0
O*IA 0.0.0.0/0 [110/65] via 23.23.23.2, 00:00:59, Serial0/0
RM-R3(config)#do ping 10.10.10.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 40/208/404 ms
RM-R3(config)#do ping 10.10.10.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 152/284/388 ms
RM-R3(config)#do ping 10.10.10.3

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 48/209/420 ms
RM-R3(config)#do ping 10.10.10.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.4, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/201/388 ms
RM-R3(config)#do ping 10.10.10.5

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.5, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 68/176/300 ms
RM-R3(config)#do ping 10.10.10.6

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.6, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 76/191/284 ms
RM-R3(config)#do ping 10.10.10.7

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.10.10.7, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 8/173/420 ms
RM-R3(config)#

Dan pastikan juga route external RIP dari RM-R3 masih bisa diterima di RM-R1

RM-R1(config-router)#do sh ip route
Codes: 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

Gateway of last resort is not set

     1.0.0.0/32 is subnetted, 1 subnets
C       1.1.1.1 is directly connected, Loopback0
     2.0.0.0/32 is subnetted, 1 subnets
O IA    2.2.2.2 [110/11] via 12.12.12.2, 00:17:21, FastEthernet0/0
     33.0.0.0/32 is subnetted, 3 subnets
O E2    33.33.33.1 [110/20] via 12.12.12.2, 00:16:12, FastEthernet0/0
O E2    33.33.33.3 [110/20] via 12.12.12.2, 00:16:12, FastEthernet0/0
O E2    33.33.33.2 [110/20] via 12.12.12.2, 00:16:12, FastEthernet0/0
     3.0.0.0/32 is subnetted, 1 subnets
O IA    3.3.3.3 [110/75] via 12.12.12.2, 00:16:21, FastEthernet0/0
     23.0.0.0/24 is subnetted, 1 subnets
O IA    23.23.23.0 [110/74] via 12.12.12.2, 00:17:24, FastEthernet0/0
     10.0.0.0/32 is subnetted, 7 subnets
C       10.10.10.2 is directly connected, Loopback2
C       10.10.10.3 is directly connected, Loopback3
C       10.10.10.1 is directly connected, Loopback1
C       10.10.10.6 is directly connected, Loopback6
C       10.10.10.7 is directly connected, Loopback7
C       10.10.10.4 is directly connected, Loopback4
C       10.10.10.5 is directly connected, Loopback5
     12.0.0.0/24 is subnetted, 1 subnets
C       12.12.12.0 is directly connected, FastEthernet0/0
RM-R1(config-router)#do ping 33.33.33.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 33.33.33.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 132/244/288 ms
RM-R1(config-router)#

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