NSSA to NSSA communication

[rocky2024]

hello, 

 

i am unable to ping from R7 to R3 and vice a versa

please help  why nssa to nssa is not pinging 

i configured default-info originate always command but still i cannot find default route in route table nor i am able to ping loopback ip.

[MHM Cisco World]

i configured default-info originate always command but still i cannot find default route in route table nor i am able to ping loopback <<- 

The nssa asbr DONT advertise defualt route if it not have defualt route in it RIB'

So did you config any static defualt route in asbr or you receive defualt route via eigrp??

Always keyword work in abr not in asbr.

MHM

[rocky2024]

Hello,

I configured with always keyword on R3 and R5 i.e. on ABR but i dont see any default route entry in R1 R2 and R6 R7 those are in NSSA area.

[MHM Cisco World]

Can you share config 

Thanks 

[rocky2024]

updated diagram below and config from ABR

R1

R1#sh run | b r o
router ospf 1
area 3 nssa
network 1.1.1.1 0.0.0.0 area 0
network 12.1.1.1 0.0.0.0 area 0
network 16.1.1.1 0.0.0.0 area 3
default-information originate always

R5

R5#sh run | b r o
router ospf 1
area 2 nssa
network 5.5.5.5 0.0.0.0 area 0
network 25.1.1.5 0.0.0.0 area 0
network 45.1.1.5 0.0.0.0 area 2
default-information originate always

 

[MHM Cisco World]

You config is correct, 
THE NSSA not accept LSA5 so the default LSA5 generate via 
defualt-infor originate always we add in two ABR (IOU5 and IOU6) is work and generate LSA5 0.0.0.0 and we can see it in IOU7
to force ABR to generate LSA7 0.0.0.0 we need 
area x nssa defualt-info originate <<- this also config in IOU5 and IOU6 and we can NOW see default 0.0.0.0 in ASBR IOU2 and IOU3 

[rocky2024]

not sure still no default route in sh ip route on R1 and R5 as per below

R1#sh run | b r o
router ospf 1
area 3 nssa default-information-originate
network 1.1.1.1 0.0.0.0 area 0
network 12.1.1.1 0.0.0.0 area 0
network 16.1.1.1 0.0.0.0 area 3

router ospf 1
area 2 nssa default-information-originate
network 5.5.5.5 0.0.0.0 area 0
network 25.1.1.5 0.0.0.0 area 0
network 45.1.1.5 0.0.0.0 area 2

sh ip route 

R5#sh ip route
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, m - OMP
n - NAT, Ni - NAT inside, No - NAT outside, Nd - NAT DIA
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
H - NHRP, G - NHRP registered, g - NHRP registration summary
o - ODR, P - periodic downloaded static route, l - LISP
a - application route
+ - replicated route, % - next hop override, p - overrides from PfR
& - replicated local route overrides by connected

Gateway of last resort is not set

1.0.0.0/32 is subnetted, 1 subnets
O 1.1.1.1 [110/3] via 25.1.1.2, 00:11:37, GigabitEthernet1
2.0.0.0/32 is subnetted, 1 subnets
O 2.2.2.2 [110/2] via 25.1.1.2, 00:11:37, GigabitEthernet1
3.0.0.0/32 is subnetted, 1 subnets
O N2 3.3.3.3 [110/20] via 45.1.1.4, 00:11:37, GigabitEthernet2
4.0.0.0/32 is subnetted, 1 subnets
--More--

R1#sh ip route
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, m - OMP
n - NAT, Ni - NAT inside, No - NAT outside, Nd - NAT DIA
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
H - NHRP, G - NHRP registered, g - NHRP registration summary
o - ODR, P - periodic downloaded static route, l - LISP
a - application route
+ - replicated route, % - next hop override, p - overrides from PfR
& - replicated local route overrides by connected

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 2.2.2.2 [110/2] via 12.1.1.2, 00:16:23, GigabitEthernet1
3.0.0.0/32 is subnetted, 1 subnets
O E2 3.3.3.3 [110/20] via 12.1.1.2, 00:16:23, GigabitEthernet1
4.0.0.0/32 is subnetted, 1 subnets
O IA 4.4.4.4 [110/4] via 12.1.1.2, 00:16:23, GigabitEthernet1
5.0.0.0/32 is subnetted, 1 subnets
--More--

[MHM Cisco World]

ABR is advertise 0.0.0.0 with always so it dont have 0.0.0.0 in RIB 
you see effect of command we enter as shown in below

NOTE:- keep in your mind that ABR of NSSA dont accept any LSA5 from other area, it translate LSA7->LSA5 

[MHM Cisco World]

friend if you more Q, I have free time to answer you. 

thanks 
MHM

[rocky2024]

Hello MHM,

I need to configure default originate on IOU2 and IOU5 as per above and see if default route getting generated or not...

Thx MHM  I will come back today EOD

[rocky2024]

Hello MHM,

i configured default info originate always under router ospf 1 on R1 and R5 (ABR) 

i configured area 2 nssa default info originate command on R6 and R4 (ASBR) 

but still i cannot see default route in nssa areas therefore i cannot reach R3 (eigrp router) from R7 (eigrp router) and vice a versa 

[MHM Cisco World]