OSPF Stub / NSSA

Answered Question
Feb 25th, 2007

Hi Expert,

In OSPF type, Can Stub area can be connected to other routing protocol ( e.g. RIP, IGRP) ?

If No, is it NSSA need to replace stub area to do it ?

I have this problem too.
0 votes
Correct Answer by sundar.palaniappan about 9 years 7 months ago

When another routing protocol/process, static/connected routes are redistributed into OSPF the router advertises them as external, type 5, LSAs. External routes can't exist in stub area.

NSSA, not-so-stubby area, is designed to address this limitation. That is, another routing protocol/process, static/connected route can be redistributed into OSPF stub area but they are advertised as type 7 LSAs. ABRs transalate the type 7 LSA to type 5, external, LSAs and advertise it to the rest of the OSPF domain.

HTH

Sundar

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 4 (1 ratings)
Loading.
Correct Answer
sundar.palaniappan Sun, 02/25/2007 - 20:09

When another routing protocol/process, static/connected routes are redistributed into OSPF the router advertises them as external, type 5, LSAs. External routes can't exist in stub area.

NSSA, not-so-stubby area, is designed to address this limitation. That is, another routing protocol/process, static/connected route can be redistributed into OSPF stub area but they are advertised as type 7 LSAs. ABRs transalate the type 7 LSA to type 5, external, LSAs and advertise it to the rest of the OSPF domain.

HTH

Sundar

acbenny Sun, 02/25/2007 - 20:31

Thx ! Sundar.

As a result, can I conclude that my previous posted message is correct

Actions

This Discussion