VOSS ISIS-OSPF Lab 1 (OSPF LSDB)

Ever wondered why certain routes do not appear in the OSPF LSDB? The GRT shows routes but you do not see them when check the LSDB. In the example topology below R1 and R2 have learnt OSPF_INTRA (preference 20) and OSPF_E2 (preference 125) routes from R3. Checking the OSPF LSDB we see the ASExternal routes but not the OSPF_INTRA routes.

ISIS-OSPF

R3 has several loopback / CLIP addresses to simulate external networks. CLIP 2 192.168.10.1/24 and CLIP 4 192.168.30.1/24 have IP OSPF Enabled and CLIP 3 192.168.20.1/24 does not have IP OSPF Enabled. OSPF redistributes direct into OSPF.

This means we have some OSPF_INTRA routes and OSPF_E2 routes advertised by R3.

On R1 or R2 type show ip ospf lsdb adv-rtr 10.255.0.6 detail to see Router Link LSAs and ASExternal LSAs.

OSPF_INTRA

 

OSPF_E2

 

R1-GRT

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s