OSPF Database

Here we’re learn how to read the OSPF LSD on a Cisco router.

Router LSAs (Type 1)

List all of a router’s links and their state. These LSAs are flooded within the area they are originated from.

R1#sh ip ospf database router ?
A.B.C.D              Link state ID (as an IP address)
adv-router           Advertising Router link states
internal             Internal LSA information
multicast            Multicast Topology
self-originate       Self-originated link states
topology             Unicast Topology
| Output modifiers
<cr>

Summarization: area n range [ip add] [mask]

RIB: O

LS ID: Originating Router ID

 

Network LSAs (Type 2)

     Produced by the DR on every multiaccess (broadcast segment, e.g. Etherenet) network. These LSAs list all attached routers, including the DR itself, they are flooded within the originating area.

     ABR sends this type of LSA ???

R1#sh ip ospf database network ?
A.B.C.D Link state ID (as an IP address)
adv-router Advertising Router link states
internal Internal LSA information
self-originate Self-originated link states
| Output modifiers
<cr>

Summarization: area n range [ip add] [mask]

RIB: O

Summary LSAs (Type 3)

     Produced by the ABRs, sent into an area to advertise destinations in other areas.

R1#sh ip osp database summary ?
A.B.C.D Link state ID (as an IP address)
adv-router Advertising Router link states
internal Internal LSA information
multicast Multicast Topology
self-originate Self-originated link states
topology Unicast Topology
| Output modifiers
<cr>

Summarization: N/A

RIB: O IA