From: sabrina pittarel (sabri_esame@yahoo.com)
Date: Fri Aug 11 2006 - 19:57:54 ART
I've done that too. No use...when I do that all routes
become with distance 109.
It simply doesn't work. Let me show you.
first some info about the network.
In my "real" topology R1 and R2, the ASBRs, are called
R3 and R4 instead, and R3 is instead R5. The ospf area
is 345, but that's the only ospf area I have i.e. it's
equivalent to area 0 and I see the issue also when I'm
really using area 0. 345 is not a stub area of any
kind.
i.e the "real" topology is :
130.1.35.0/24
R3 -------
|
R5
|
R4 -------
130.1.45.0/24
130.1.78.0 is one of the redistributed networks:
show ip route:
---------------
<snip>
O E2 130.1.78.0/24 [109/20] via 130.1.45.4,
00:02:19, Serial1/1
[109/20] via 130.1.35.3,
00:02:19, Serial1/0
show ip route 130.1.78.0:
--------------------------
Routing entry for 130.1.78.0/24
Known via "ospf 1", distance 109, metric 20
Tag 345, type extern 2, forward metric 64
Last update from 130.1.45.4 on Serial1/1, 00:03:12
ago
Routing Descriptor Blocks:
130.1.45.4, from 150.1.4.4, 00:03:12 ago, via
Serial1/1
Route metric is 20, traffic share count is 1
Route tag 345
* 130.1.35.3, from 150.1.3.3, 00:03:12 ago, via
Serial1/0
Route metric is 20, traffic share count is 1
Route tag 335
Now my configuration:
----------------------
router ospf 1
router-id 150.1.5.5
log-adjacency-changes
network 130.1.35.0 0.0.0.7 area 345
network 130.1.45.0 0.0.0.255 area 345
neighbor 130.1.35.3
distance 109 150.1.4.4 0.0.0.0 1
distance 110 150.1.3.3 0.0.0.0 1
The ACL :
Standard IP access list 1
10 deny 150.1.3.0, wildcard bits 0.0.0.255 (2
matches)
20 permit any (43 matches)
Rack1R5#
It simply doesn't work.
Sabrina
--- Wayne <ccie_lab@inetiq.com> wrote:
> The route-source is the border router that sends in
> the route. In this case
> R1 and R2 are ASBRs and will send in external
> networks into the ospf domain,
> so they will be the route-source for the distance
> command. You could use
> 110 for r1 and 109 for r2. This should solve your
> issue.
>
> In a multi-area network the ABR will be the
> route-source.
>
> Regards,
>
> wayne
>
> -----Original Message-----
> From: nobody@groupstudy.com
> [mailto:nobody@groupstudy.com] On Behalf Of
> sabri_esame@yahoo.com
> Sent: Friday, August 11, 2006 4:50 PM
> To: ccielab@groupstudy.com
> Subject: OSPF and the distance command
>
> Hi all,
> I'm trying to understand how ospf behaves in
> relation with the following
> command:
>
> distance <#> <route-source> <wildcard> <acl>
>
> I have the following topology:
>
>
> R1 --------
> |
> R3
> |
> R2 --------
>
>
>
> R1, R2 and R3 are all in area 0. All routers have
> their loopbacks advertised
> in area0.
>
> R1 and R2 are also ASBRs and can reach the same set
> of external networks.
>
> I want to configure R3 in such a way it will forward
> all traffic for
> external networks to R2.
> I know I can accomplish that modifying the
> redistribution metrics in R1 and
> R2, but as I said I'm trying to understand how the
> *distance* command
> behaves.
>
> I thought I could solve the problem doing the
> following:
>
> R3
> ---
>
> router ospf #
> distance 109 <R2 RID> 0.0.0.0 1
>
> access-list 1 deny <R1's loopback>
> access-list 1 permit any
>
> but it doesn't work.
>
> All external routes are still load balanced between
> R1 and R2 and show up in
> the routing table with AD 110.
> The only route with AD = 109 is R2's loopback. If I
> remove the acl from the
> distance command, i.e.
>
> distance 109 <R2 RID> 0.0.0.0
>
> also R1's loopback will be shown with distance 109
> and R2 will be preferred
> (!!!). All other routes will still be load balanced
> and will have AD 110
>
> Only if I shut the link between R1 and R3 I finally
> see these routes with an
> AD of 109.
>
> I really don't understand what is going on, any
> ideas?
>
>
> Thanks
> Sabrina
>
>
This archive was generated by hypermail 2.1.4 : Fri Sep 01 2006 - 15:41:56 ART