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OSPF Routes NOT in database but in Routing Table (You read it correct)

gasaini2
Level 1
Level 1

Hi All,

I've a lab of two routes R1 & R2 (Connected with Ethernet Link)  like : R1<------------------>R2

I can see, OSPF learned routes are in Routing Table But not in Database (You read it correct).

How can it be possible ?? I've seen the other way many times i.e. Routes in database but not in Routing table (Like, L3 VPN at remote end when we need to use capability VRF-lite, or we're trying to suppress LSA's of inter-area route but that's not concern here)

I've captured few logs & Running Configuration of both routers. Please check and let me know what I'm doing wrong.

I've cleared the OSPF neighborship multiple times but still same. Tried to bounce e1/1 on R2, but no luck.

R2#ping 3.3.3.3 so lo3

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to 3.3.3.3, timeout is 2 seconds:

Packet sent with a source address of 2.2.2.2

!!!!!

Success rate is 100 percent (5/5), round-trip min/avg/max = 64/76/108 ms

R2#

R1

R1#

R1#show ip os int brief

Interface    PID   Area            IP Address/Mask    Cost  State Nbrs F/C

Lo0          1     0               9.9.0.1/32         1     LOOP  0/0

Lo3          1     0               3.3.3.3/32         1     LOOP  0/0

Et1/0        1     0               9.9.12.1/24        10    DR    1/1

R1#

R1#

R1#show ip ospf da

            OSPF Router with ID (9.9.12.1) (Process ID 1)

                Router Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum Link count

9.9.12.1        9.9.12.1        255         0x80000028 0x00BE86 3

9.9.12.2        9.9.12.2        256         0x80000032 0x0067F8 2

                Net Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum

9.9.12.1        9.9.12.1        255         0x80000003 0x00BDFC

R1#

R1#

R1#show ip route | b Gate

Gateway of last resort is not set

      2.0.0.0/32 is subnetted, 1 subnets

O        2.2.2.2 [110/11] via 9.9.12.2, 00:04:17, Ethernet1/0

      3.0.0.0/32 is subnetted, 1 subnets

C        3.3.3.3 is directly connected, Loopback3

      9.0.0.0/8 is variably subnetted, 3 subnets, 2 masks

C        9.9.0.1/32 is directly connected, Loopback0

C        9.9.12.0/24 is directly connected, Ethernet1/0

L        9.9.12.1/32 is directly connected, Ethernet1/0

R1#

R1#

R1#show ip os ne

Neighbor ID     Pri   State           Dead Time   Address         Interface

9.9.12.2          1   FULL/BDR        00:00:36    9.9.12.2        Ethernet1/0

R1#

R1#

R1#show run | s r o

router ospf 1

 log-adjacency-changes

R1#

R1#

*************  R2  ********************

R2#

R2#show ip os int brief

Interface    PID   Area            IP Address/Mask    Cost  State Nbrs F/C

Lo3          1     0               2.2.2.2/32         1     LOOP  0/0

Et1/1        1     0               9.9.12.2/24        10    BDR   1/1

R2#

R2#

R2#show run | s router o

router ospf 1

 log-adjacency-changes

 passive-interface Loopback3

 network 2.2.2.2 0.0.0.0 area 0

 network 9.9.12.0 0.0.0.255 area 0

R2#

R2#show ip os da

            OSPF Router with ID (9.9.12.2) (Process ID 1)

                Router Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum Link count

9.9.12.1        9.9.12.1        326         0x80000028 0x00BE86 3

9.9.12.2        9.9.12.2        325         0x80000032 0x0067F8 2

                Net Link States (Area 0)

Link ID         ADV Router      Age         Seq#       Checksum

9.9.12.1        9.9.12.1        326         0x80000003 0x00BDFC

R2#

R2#

R2#show ip route | b Gate

Gateway of last resort is not set

      2.0.0.0/32 is subnetted, 1 subnets

C        2.2.2.2 is directly connected, Loopback3

      3.0.0.0/32 is subnetted, 1 subnets

O        3.3.3.3 [110/11] via 9.9.12.1, 00:05:22, Ethernet1/1

      9.0.0.0/8 is variably subnetted, 3 subnets, 2 masks

O        9.9.0.1/32 [110/11] via 9.9.12.1, 00:05:22, Ethernet1/1

C        9.9.12.0/24 is directly connected, Ethernet1/1

L        9.9.12.2/32 is directly connected, Ethernet1/1

R2#

R2#

R2#show ip os ne

Neighbor ID     Pri   State           Dead Time   Address         Interface

9.9.12.1          1   FULL/DR         00:00:30    9.9.12.1        Ethernet1/1

R2#

R2#

1 Accepted Solution

Accepted Solutions

Rolf Fischer
Level 9
Level 9

Hi,

an OSPF router generates only one Router-LSA (Type-1) per Area.This Router-LSA contains a list with all links in that Area.

You can see your Loopbacks with 'show ip ospf database router' - 'show ip ospf database' rather provides an overview:

Router Link States (Area 0)
Link ID         ADV Router      Age         Seq#       Checksum Link count
9.9.12.1        9.9.12.1        326         0x80000028 0x00BE86 3

Router 9.9.12.1 advertises one Router-LSA for Area 0 and the LSA contains 3 links. Apparently you've created the Loopback IPs when the adjacency was already formed, otherwise the Router ID would be set to the highest Loopback IP (perhaps that's the reason for your confusion).

HTH
Rolf

View solution in original post

1 Reply 1

Rolf Fischer
Level 9
Level 9

Hi,

an OSPF router generates only one Router-LSA (Type-1) per Area.This Router-LSA contains a list with all links in that Area.

You can see your Loopbacks with 'show ip ospf database router' - 'show ip ospf database' rather provides an overview:

Router Link States (Area 0)
Link ID         ADV Router      Age         Seq#       Checksum Link count
9.9.12.1        9.9.12.1        326         0x80000028 0x00BE86 3

Router 9.9.12.1 advertises one Router-LSA for Area 0 and the LSA contains 3 links. Apparently you've created the Loopback IPs when the adjacency was already formed, otherwise the Router ID would be set to the highest Loopback IP (perhaps that's the reason for your confusion).

HTH
Rolf