From: Albert Lu (albert_lu@optushome.com.au)
Date: Wed Oct 02 2002 - 01:00:50 GMT-3
The nature of OSPF is to route packets through shortest path, there is no
traffic engineering that you can do like you can with BGP or MPLS (although
that is based on BGP) to select what goes where.
However there are some 'hacks' you could probably do such as redistribute
the OSPF routes that you want into another OSPF process. But I wouldn't
really recommend it if you were doing it on a production network, as it can
get ugly.
You might want to step out of the box and re-evaluate what you are trying to
solve, to see whether the problem really is the intra/inter area selection
process of OSPF.
Albert
-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]On Behalf Of
Jay
Sent: Wednesday, October 02, 2002 11:19 AM
To: albert_lu@optushome.com.au; 'P729'; ccielab@groupstudy.com
Subject: Re: OSPF riddle -how to manipulate the OSPF prefer inter area
over intra area
Albert is correct.
I have tried the distance command but it is not working the way its suppose
to. I was just wondering if theres a way to break the intra area over inter
area rule. Only way I was able to fix this is to put the ISDN in a different
area. I have spent quite some time on this, but am still pulling my hair,
because I just can't figure out anymore ways to manipulate this. Before I
give up and conclude that Intra Area routes will be prefered first no matter
what and theres no way to break this rule, I thought I ask you guys.
thanks,
Jay
----- Original Message -----
From: "Albert Lu" <albert_lu@optushome.com.au>
To: "'P729'" <p729@cox.net>; "'Jay'" <ccienxtyear@hotmail.com>;
<ccielab@groupstudy.com>
Sent: Tuesday, October 01, 2002 6:03 PM
Subject: RE: OSPF riddle -how to manipulate the OSPF prefer inter area over
intra area
> distance ospf command isn't going to work like it would with distance
vector
> protocols such as rip. Since you would have to set distance on the basis
of
> the source of the routes, which would not be tne next hop like rip but
would
> be the originator of the LSA for OSPF. Distance command looks at the
> router-id which can be many hops away.
>
> -----Original Message-----
> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com]On Behalf Of
> P729
> Sent: Wednesday, October 02, 2002 8:37 AM
> To: Jay; ccielab@groupstudy.com
> Subject: Re: OSPF riddle -how to manipulate the OSPF prefer inter area
> over intra area
>
>
> I haven't analyzed your topology, but just focusing on this statement:
> "...running into a few issues with the OSPF route selction process of
> preferring intra area over inter area routes."
>
> --you can modify the AD of each type of OSPF route independently. See the
> 'distance ospf' command...
>
> Regards,
>
> Mas Kato
> https://ecardfile.com/id/mkato
> ----- Original Message -----
> From: "Jay" <ccienxtyear@hotmail.com>
> To: <ccielab@groupstudy.com>
> Sent: Tuesday, October 01, 2002 1:52 PM
> Subject: OSPF riddle -how to manipulate the OSPF prefer inter area over
> intra area
>
>
> Folks,
>
> I have attached a topolgy that I am working on for simplicity, heres the =
> problem -
> I am trying to get a OSPF setup done and running into a few issues with =
> the OSPF route selction process of preferring intra area over inter area =
> routes. the requirement is that..The ISDN link between R2 and R5 shd be =
> acctive only when the FR cloud is down. I am using OSPF demand circuit =
> ..Since R5 is now part of Area 1 the loopbacks on R2 and R4 are now seen =
> as intra area routes and the ISDN route is prefferrd over the ethernet =
> route. I tried to use the distance command and with one and then with =
> two ospf process. Also an intersting thing here is that the External =
> routes for RIP and EIGRP are also learnt through the BRI even after =
> canging the redistributed route type to E1 to include internal cost. I =
> am not if I am missing something here
>
> R3 is connected via Ethernet to the Area 0. I forgot to put that on the =
> drawing.
> My configurations are simple..partial configs
>
> R5
>
> router ospf 1
>
> network 150.35.15.0 0.0.0.255 area 0
>
> network 50.1.1.0 0.0.0.255 area 1
>
> network 5.5.5.0 0.0.0.255 are 0
>
> router-id 5.5.5.5
>
> redistribute eigrp 1 subnets route-map eigrp2ospf
>
> R2
>
> router ospf 1
>
> network 150.35.24.0 0.0.0.244 are 1
>
> network 50.1.1.0 0.0.0.255 are 1
>
> network 2.2.2.0 0.0.0.255 are 1
>
> redisribute rip subnets route-map rip2ospf
>
> Interface bri 0/0
>
> ip add 50.1.1.2 255.255.255.0
>
> ip ospf demand circuit
>
> ip ospf cost 1500
>
> [GroupStudy.com removed an attachment of type image/gif which had a name
of
> pref.gif]
This archive was generated by hypermail 2.1.4 : Tue Nov 05 2002 - 08:35:36 GMT-3