[c-nsp] OSPF Cost vs Injected Default Route

[a. Rahman Isnaini R suTan]

Sorry, right..
The primary link found down.
Thanks.

Salam,
a. Rahman Isnaini r. Sutan



----- Original Message ----- 
From: "Oliver Boehmer (oboehmer)" <oboehmer at cisco.com>
To: "a. Rahman Isnaini R suTan" <risnaini at indo.net.id>; 
<cisco-nsp at puck.nether.net>
Sent: Thursday, March 23, 2006 11:50 PM
Subject: RE: OSPF Cost vs Injected Default Route



> Let say 3 routers A, B and C running OSPF.
> A is ASBR, connected to B and C
> C connected to A directly & via B.
>
> For router C which connected with two links :
>     - Primary (w/ default route injected from A)
>     - Secondary (w/ static default route + metric >110 to B)
>
> In case of bad quality of primary link (not fully disconnected), I
> set cost 5000 on interface router A towards C.
> The default route changed to secondary.
>
> How cost can affect the changing of default route ?

Not sure I grasp the full picture, but if you change the ospf cost on
the link from A to C (and only on A's side), the SPF on C should not
change at all (as his cost to A is still the same), so I'm a bit
puzzled.
Your static default route on C (with an admin distance of >110) should
only become active if there is no OSPF default route anymore, and this
should not happen if you just change the cost of a link.
Can you check the FA of the default route (see also
http://www.cisco.com/en/US/partner/tech/tk365/technologies_tech_note0918
6a008009405a.shtml#t3)..

oli