Re: OSPF LSA type 3 filtering

Sorry, like Narbik shows in has lab, area range only works with intra area
routes.

It's also worth mentioning that using a distribute-list only stops LSA type
3 *re-generation*(and filters from the RIB). But type 3 LSAs will still get
generated if you're filtering *intra* area routes with a distribute list.

-Yuri

On Wed, Jan 2, 2013 at 11:32 AM, Yuri Bank <yuribank_at_gmail.com> wrote:

> Both of these commands will affect the ospf database, and neither will
> affect the local routing table of the ABR that uses them.
>
> *area range - with not-advertise will prevent LSA type 3 generation to ALL
> areas. Affects OSPF Intra area, and inter-area learned routes only.
>
> *area filter-list - Is very similar to area range with not-advertise, in
> the way it affects the actual OSPF database, but allows you to be a bit
> more granular. For example: You have an ABR connected to AREA 0, 10, 20,
> and 30. You want to stop some routes from AREA 10, going to AREA 20. "area
> 20 filter-list prefix foo-routes in". Affects OSPF Intra area, and
> inter-area learned routes only.
>
> -Yuri
>
>
> On Tue, Jan 1, 2013 at 10:41 PM, ccie99999 <ccie99999_at_gmail.com> wrote:
>
>> Sara, as far as I know it works in this way:
>>
>> with the first option, the filter-list you can filter only lsa type 3 and
>> this filtering only affects the local routing table, not the OSPF
>> database.
>>
>> with the second option you are filtering every LSA type but this filtering
>> affect the OSPF database, therefore also the local routing table.
>>
>> There is another option that applies to route summarization when
>> distributing routes into OSPF. This also has the feature "not-advertise",
>> and the syntax is: summary-address ip-prefix summary-mask [not-advertise]
>>
>> I hope someone else can add more details.
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> On Wed, Jan 2, 2013 at 5:16 AM, Sarad <tosara_at_gmail.com> wrote:
>>
>> > Hi Experts,
>> >
>> > Can somebody help me to get my head around this, I've been labbing ospf
>> > type 3 filtering, Main method use for this is filter-list command.
>> Which we
>> > can use to filter route based on the direction (in /out)
>> >
>> >
>> >
>> > Then there is area range command with not-advertise switch we can use
>> to do
>> > limited filtering on ABR. When I tested this it only works when I filter
>> > LSA type 3 from non backbone area to a backbone area.
>> >
>> > Can somebody help me to explain what is the exact usage of this command
>> in
>> > term of filtering in OSPF. There is nothing much in the doc CD
>> >
>> > *
>> > *
>> > *area area-id filter-list prefix prefix-list-name {in | out}
>> > area* area-id *range* ipv6-prefix /prefix-length [*advertise* | *
>> > not-advertise*] [*cost* cost]
>> >
>> >
>> > Cheers
>> > Sara
>> >
>> >
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>> >
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>> >
>> >
>> >
>> >
>> >
>>
>>
>> --
>> @ccie99999
>>
>>
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Received on Wed Jan 02 2013 - 15:22:22 ART