Re: OSPF Order of Preference

I recently saw a scenario, where two routes(E1 and N1) having Equal Cost,
were load balancing.
As soon as N1 was stripped of its FA, E1 became a preferred route.

Nick
GREENNET
Lat: 41043'25.46"N
Long: 44045'45.60"E

On Sat, Jul 4, 2009 at 11:51 AM, Lejoe <styran_at_gmail.com> wrote:

> Hi Nick,
>
> I dont think the Forwarding Address should be part of the criteria because
> when two type 5 LSAs (assuming E1) to the same destination exists, one
with
> FW address set and the other without.
>
> In this case, the LSA to be installed in the routing table of a router is
> based on the comparison that router's metric to the ASBR that generated the
> LSA with a forwarding address of 0.0.0.0 to that router's metric to reach
> the forwarding address of X , which was set for the LSA generated by the
> ASBR.
>
> Now assuming the metric was equal, I would believe the result is load
> balancing across the two paths. Hope that someone can shed more light on
> this. (equal costs with FW and without FW)
>
>
> Regards
>
> Lejoe
>
>
> On Sat, Jul 4, 2009 at 5:00 PM, Nicholas Davitashvili
<nickda_at_gmail.com>wrote:
>
>> Additional criteria of course would be that costs are equal.
>>
>> Nick
>> GREENNET
>> Lat: 41043'25.46"N
>> Long: 44045'45.60"E
>>
>>
>> On Sat, Jul 4, 2009 at 10:26 AM, Nicholas Davitashvili
>> <nickda_at_gmail.com>wrote:
>>
>> > Hi Group,
>> >
>> > If anyone can confirm this order of preference in OSPF, I'd be really
>> > greatful.
>> > If it is wrong, please give the correct order:
>> >
>> > 1. O - OSPF Intra-Area
>> > 2. IA - OSPF Inter-Area
>> > 3. E1 /w FA -- External Type 1 With Forwarding Address
>> > 4. N1 /w FA
>> > 5. E1 /wo FA -- Ext. Type 1 with Forwarding Address set to 0.0.0.0
>> > 6. N1 /wo FA
>> > 7. E2 /w FA
>> > 8. N2 /w FA
>> > 9. E2 /wo FA
>> > 10. N2 /wo FA
>> >
>> > Thanks in advance!
>> >
>> > Nick
>> > GREENNET
>> > Lat: 41043'25.46"N
>> > Long: 44045'45.60"E

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Received on Sat Jul 04 2009 - 12:51:32 ART