From: Paul Cosgrove (paul.cosgrove@heanet.ie)
Date: Fri Apr 11 2008 - 06:44:05 ART
Hi Imran,
Interesting. "Optimal routing design" discusses the two database filter
commands with hub and spoke on pages 177/178. The section ends with:-
"You can also originate a default route at the ABR using
default-information originate instead of static routes at the
remote-routers. The command ip ospf database-filter all out only
filteres learned LSAs, not locally originated ones, so a locally
generated default would still be sent to the remote routers"
The preceding example in the book is a partial config which doesn't
specify an area type. I wonder if the different behaviour is related to
the LSA type of the default, which with the totally stub will have to be
Type 3?
Paul.
Mohmmad, Imran wrote:
> It will block the advertisement of all LSA from interface including the
> default.
>
> DS1/0--------S1/1RP
> |
> |
> S1/0
> A
> |
> |
> /\
> / \
> / \
> S1/0 S1/0
> B C
>
> Router D, RP and router A S1/0 is in area 0 and the router A se1/1 and
> s1/2 in area 45 with two different point to point links.
>
> Once we configured the area 45 as totally-stub the OIA SLA that we can
> see on B and C is the default route and Router SLA for C link to router
> A
>
> A#sh run | sec router ospf
> router ospf 10
> log-adjacency-changes
> area 45 stub no-summary
> network 10.10.10.3 0.0.0.0 area 45 <Link to router C>
> network 40.40.40.3 0.0.0.0 area 45<Link to router B>
> network 192.168.30.3 0.0.0.0 area 0
>
>
> B#sh ip os database
>
> OSPF Router with ID (2.2.2.2) (Process ID 10)
>
> Router Link States (Area 45)
>
> Link ID ADV Router Age Seq# Checksum Link
> count
> 2.2.2.2 2.2.2.2 569 0x80000001 0x007291 2
> 3.3.3.3 3.3.3.3 663 0x80000004 0x00E2C9 2
> 150.1.3.3 150.1.3.3 588 0x8000000B 0x00DD9C 4
>
> Summary Net Link States (Area 45)
>
> Link ID ADV Router Age Seq# Checksum
> 0.0.0.0 150.1.3.3 677 0x80000001 0x003769
>
> B#sh ip route ospf
> 10.0.0.0/24 is subnetted, 1 subnets
> O 10.10.10.0 [110/128] via 40.40.40.3, 00:02:59, Serial1/0
> O*IA 0.0.0.0/0 [110/65] via 40.40.40.3, 00:02:59, Serial1/0
>
> A#sh run int se1/1
> Building configuration...
>
> Current configuration : 198 bytes
> !
> interface Serial1/1
> description ****Connected to B******
> ip address 40.40.40.3 255.255.255.0
> ip pim sparse-mode
> encapsulation ppp
> ip ospf database-filter all out
> serial restart-delay 0
>
> Once we filter-lsa advertisement on A, the B router is no longer have
> any OSPF LSA including the default Summary.
>
> B#sh ip os database
>
> OSPF Router with ID (2.2.2.2) (Process ID 10)
>
> Router Link States (Area 45)
>
> Link ID ADV Router Age Seq# Checksum Link
> count
> 2.2.2.2 2.2.2.2 3 0x80000001 0x007291 2
> B#
> B#
> B#sh ip os database
>
> OSPF Router with ID (2.2.2.2) (Process ID 10)
>
> Router Link States (Area 45)
>
> Link ID ADV Router Age Seq# Checksum Link
> count
> 2.2.2.2 2.2.2.2 6 0x80000001 0x007291 2
> B#sh ip route ospf
>
>
> Imran
>
>
>
> -----Original Message-----
> From: Paul Cosgrove [mailto:paul.cosgrove@heanet.ie]
> Sent: Thursday, April 10, 2008 3:14 AM
> To: nagendra kumar
> Cc: Mohmmad, Imran; atif raees; ccielab@groupstudy.com
> Subject: Re: OSPF Inra Area route filtering
>
> The command filters learned LSAs from being relayed on, so you should
> still be able to send a default from the hub.
>
> Paul.
>
> nagendra kumar wrote:
>> Hi,
>>
>> I guess this command will filter all LSAs and so itz our
> responsibility to configure a default route in all spoke routers.
>>
>> Regards,
>> Nagendra
>>
>> Paul Cosgrove <paul.cosgrove@heanet.ie> wrote: neighbor x.x.x.x
> database-filter all out
>> Paul.
>>
>> Mohmmad, Imran wrote:
>>> Hi there,
>>>
>>> What you want to filter, route entering into the routing table from
> OSPF
>>> LSDB or the inter-area LSA itself?
>>>
>>> If you want to filter the route entering from OSPF LSDB to routing
> table
>>> you can use the distribute-list in on OSPF process,
>>>
>>> If you want to filter the Intra-Area LSA itself, then with in an area
> it
>>> is not possible.
>>>
>>> Imran
>>>
>>> -----Original Message-----
>>> From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf
> Of
>>> atif raees
>>> Sent: Wednesday, April 09, 2008 1:15 AM
>>> To: ccielab@groupstudy.com
>>> Subject: OSPF Inra Area route filtering
>>>
>>> Dear all
>>>
>>> i am experimenting a hub & spoke topology using FR.
>>>
>>> Each spoke has it on LAN
>>>
>>> Hub has area 0 & area 1 as totally stub are all FR spoke are in Area
> 1
>>> what i want to achieve is to filter (intra area ospf routes sent by
> each
>>> spoke) at hub site so that spoke can has just default route in it
>>> routing
>>> table which they already have as i have configured area 1 as totally
>>> stub.
>>>
>>> is it possible.
>>>
>>> Atif Raees
>>>
>>>
>>>
>>> _________________________________________________________________
>>> Pack up or back upuse SkyDrive to transfer files or keep extra
> copies.
>>> Learn
>>> how.
>>>
> hthttp://www.windowslive.com/skydrive/overview.html?ocid=TXT_TAGLM_WL_Re
>>> fresh
>>> _skydrive_packup_042008
>>>
>>>
> _______________________________________________________________________
>>> Subscription information may be found at:
>>> http://www.groupstudy.com/list/CCIELab.html
>>>
>>>
> _______________________________________________________________________
>>> Subscription information may be found at:
>>> http://www.groupstudy.com/list/CCIELab.html
>>>
>>
>
>
-- HEAnet Limited Ireland's Education & Research Network 5 George's Dock, IFSC, Dublin 1, Ireland Tel: +353.1.6609040 Web: http://www.heanet.ie Company registered in Ireland: 275301Please consider the environment before printing this e-mail.
Pass the CCIE in six weeks, Guaranteed! http://www.certscience.com/CCIE
This archive was generated by hypermail 2.1.4 : Thu May 01 2008 - 08:25:50 ART