Re: OSPF Order of Preference

Hi,

Yes ofcourse E1 will always be preferred over N1 (if both N1 and E1 have
same cost) . I was talking about two E1s with Fowarding address set and
without forwarding address set (FW:0.0.0.0)

Lejoe

On Sat, Jul 4, 2009 at 6:51 PM, Nicholas Davitashvili
<nickda_at_gmail.com>wrote:

> 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 - 19:52:05 ART