Downward bit not supported in Type-5 LSA?????

mahiralimahirali ✭✭
in CCIE Service Provider Technical

Hi Everyone,

I was just trying to understand multi vrf sites and came across this issue. I am using the topology of Brian's lecture.

On my R02
=======

R02#sh ip ospf da

            OSPF Router with ID (2.2.2.2) (Process ID 1)

                Router Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum Link count
1.1.1.1         1.1.1.1         249         0x8000000E 0x00A04A 2
2.2.2.2         2.2.2.2         248         0x80000011 0x006190 1
19.19.19.19     19.19.19.19     1089        0x8000000C 0x00F40E 1
20.20.20.20     20.20.20.20     2     (DNA) 0x8000000C 0x009E86 3

                Net Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum
10.1.2.2        2.2.2.2         248         0x80000009 0x0011FD
10.1.20.20      20.20.20.20     2     (DNA) 0x80000001 0x0049FC
10.19.20.20     20.20.20.20     1189        0x80000004 0x00966E

                Summary Net Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum
10.4.10.0       2.2.2.2         1311        0x80000002 0x00ACED
10.4.10.0       19.19.19.19     1248        0x80000003 0x00AAAA
10.10.10.10     2.2.2.2         1311        0x80000002 0x000A7F
10.10.10.10     19.19.19.19     1248        0x80000003 0x00083C

                Type-5 AS External Link States

Link ID         ADV Router      Age         Seq#       Checksum Tag
10.0.0.2        2.2.2.2         540         0x80000002 0x009FC9 3489661028
10.0.0.2        19.19.19.19     2397        0x80000001 0x001A8B 3489661028
10.0.0.19       2.2.2.2         540         0x80000002 0x006D6A 3489661028
10.0.0.19       19.19.19.19     2362        0x80000001 0x00F61E 3489661028
10.1.20.0       2.2.2.2         3607        0x80000002 0x00399D 3489661028
10.19.20.0      2.2.2.2         14          0x80000001 0x006C58 3489661028
20.20.20.20     2.2.2.2         3607        0x80000002 0x00099C 3489661028
=========

and on my R01
==========

R01#sh ip osp da

            OSPF Router with ID (1.1.1.1) (Process ID 1)

                Router Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum Link count
1.1.1.1         1.1.1.1         305         0x8000000E 0x00A04A 2
2.2.2.2         2.2.2.2         306         0x80000011 0x006190 1
19.19.19.19     19.19.19.19     1147        0x8000000C 0x00F40E 1
20.20.20.20     20.20.20.20     3     (DNA) 0x8000000C 0x009E86 3

                Net Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum
10.1.2.2        2.2.2.2         306         0x80000009 0x0011FD
10.1.20.20      20.20.20.20     3     (DNA) 0x80000001 0x0049FC
10.19.20.20     20.20.20.20     1247        0x80000004 0x00966E

                Summary Net Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum
10.4.10.0       2.2.2.2         1369        0x80000002 0x00ACED
10.4.10.0       19.19.19.19     1306        0x80000003 0x00AAAA
10.10.10.10     2.2.2.2         1369        0x80000002 0x000A7F
10.10.10.10     19.19.19.19     1306        0x80000003 0x00083C

                Type-5 AS External Link States

Link ID         ADV Router      Age         Seq#       Checksum Tag
10.0.0.2        2.2.2.2         598         0x80000002 0x009FC9 3489661028
10.0.0.2        19.19.19.19     2456        0x80000001 0x001A8B 3489661028
10.0.0.19       2.2.2.2         598         0x80000002 0x006D6A 3489661028
10.0.0.19       19.19.19.19     2420        0x80000001 0x00F61E 3489661028
10.1.20.0       2.2.2.2         56          0x80000003 0x004B88 3489661028
10.19.20.0      2.2.2.2         73          0x80000001 0x006C58 3489661028
20.20.20.20     2.2.2.2         56          0x80000003 0x001B87 3489661028
==========

as per the lecture these Type 5 should be in routing table.

Here is the routing table of R01
====================

R01#sh ip ro vrf a

Routing Table: a
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
       a - application route
       + - replicated route, % - next hop override

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
      10.0.0.0/8 is variably subnetted, 3 subnets, 2 masks
O E2     10.0.0.2/32 [110/1] via 10.1.2.2, 00:09:14, GigabitEthernet0/1.12
C        10.1.2.0/24 is directly connected, GigabitEthernet0/1.12
L        10.1.2.1/32 is directly connected, GigabitEthernet0/1.12
========================

here is the database of one of the Type-5 on R01
=================================

R01#sh ip ospf da ex 20.20.20.20

            OSPF Router with ID (1.1.1.1) (Process ID 1)

                Type-5 AS External Link States

  LS age: 70
  Options: (No TOS-capability, DC, Downward)
  LS Type: AS External Link
  Link State ID: 20.20.20.20 (External Network Number )
  Advertising Router: 2.2.2.2
  LS Seq Number: 80000003
  Checksum: 0x1B87
  Length: 36
  Network Mask: /32
        Metric Type: 2 (Larger than any link state path)
        MTID: 0
        Metric: 2
        Forward Address: 0.0.0.0
        External Route Tag: 3489661028

=========

Any thoughts, suggestion and ideas.

Thanks and Regards,

Mahir

 

· Share on FacebookShare on Twitter

Comments

Sign In or Register to comment.