Re: split horizon

Hey Jack,
I'm sorry about the email yesterday... I was just disgusted about the fact
that you suggested split horizon for a LSR protocol.
I must admit I v learnt alot from this thread you started, it was really my
bad...

On Wed, Jan 6, 2010 at 6:03 PM, Bobola Oke <okebobola_at_gmail.com> wrote:

> Hey Jack,
> I'm sorry about the email yesterday... I was just disgusted about the fact
> that you suggested split horizon for a LSR protocol.
> I must admit I v learnt alot from this thread you started, it was really my
> bad...
>
>
> On Wed, Jan 6, 2010 at 9:39 AM, jack daniels <jckdaniels12_at_gmail.com>wrote:
>
>> only thing what i could though of was staic default routes at CE SPOKE to
>> PE
>> ...As PE have default route orignated from HUB. Any other option please
>> suggest.
>>
>> On Wed, Jan 6, 2010 at 1:26 PM, jack daniels <jckdaniels12_at_gmail.com>
>> wrote:
>>
>> > yeah but PE can't configure , have access to all CE
>> >
>> >
>> > On Wed, Jan 6, 2010 at 1:19 PM, <olukolade_at_gmail.com> wrote:
>> >
>> >> Hi,
>> >>
>> >> What you need to do is At the hub site PE, use the 'network 0.0.0.0'
>> under
>> >> bgp to bring the default route being learnt by ospf from the hub CE
>> into
>> >> bgp. At the spoke site PEs, configure ' default-information originate'
>> in
>> >> ospf. This will make the remote PE advervise the exsting default route
>> which
>> >> would have been learnt via bgp to the spoke CE. This way you get your
>> hub
>> CE
>> >> default route at the spoke sites.
>> >>
>> >> Cheers,
>> >>
>> >> Kolade
>> >>
>> >> Sent from my BlackBerry. wireless handheld from Glo Mobile.
>> >> ------------------------------
>> >> *From: *jack daniels <jckdaniels12_at_gmail.com>
>> >> *Date: *Wed, 6 Jan 2010 09:44:14 +0530
>> >> *To: *Mirco Orlandi<mirco.orlandi_at_gmail.com>
>> >> *Cc: *swap m<ccie19804_at_gmail.com>; Bryan Bartik<bbartik_at_ipexpert.com>;
>> <
>> >> olukolade_at_gmail.com>; <Charles.Henson_at_regions.com>; Cisco
>> certification<
>> >> ccielab_at_groupstudy.com>; Marko Milivojevic<markom_at_ipexpert.com>; <
>> >> nobody_at_groupstudy.com>
>> >> *Subject: *Re: split horizon
>> >>
>> >> Yeah that works , but for internet default route also required .... so
>> if
>> >> I do defaul-in orignate alsways at HUB >>>>> but OSPF SPOKES won't
>> learn
>> it
>> >> ( as OSPF does'nt learn default route via redistribution)....BGP>>>OSPF
>> >> redistribution at remote PE (for SPOKE CE)
>> >>
>> >> On Wed, Jan 6, 2010 at 4:04 AM, Mirco Orlandi
>> <mirco.orlandi_at_gmail.com>wrote:
>> >>
>> >>> Yes,
>> >>> if spokes are 10.0.1.0/24, 10.0.2.0/24, 10.0.3.0/24, and so on...,
>> with
>> >>> a 10.0.0.0/16 to null0 redistributed on hub ce and accepted from all
>> >>> spokes, it works for going and returning traffic with a single
>> blackhole
>> >>> advertise. This is what i mean.
>> >>>
>> >>> ...go back to ios
>> >>> m.
>> >>>
>> >>>
>> >>> On Tue, Jan 5, 2010 at 11:17 PM, swap m <ccie19804_at_gmail.com> wrote:
>> >>>
>> >>>> Bryan,
>> >>>>
>> >>>> it can look something like this.
>> >>>>
>> >>>> on Hub,
>> >>>> 1. add a static 1.1.1.0/23 to null0
>> >>>> 2. redis this into OSPF on hub
>> >>>> 3. this will reach spoke1 via Hub-PE-CE ospf and then MPBGP and then
>> >>>> Spoke1-PE-CE OSPF.... Spoke2 can be specially filtered as it doesnt
>> need
>> >>>> this blackhole route.
>> >>>>
>> >>>> Swap
>> >>>> #19084
>> >>>>
>> >>>> On Wed, Jan 6, 2010 at 1:58 AM, Bryan Bartik
>> <bbartik_at_ipexpert.com>wrote:
>> >>>>
>> >>>>> Mirco,
>> >>>>>
>> >>>>> I have not seen that example before. Can you post an example of the
>> Hub
>> >>>>> CE
>> >>>>> config?
>> >>>>>
>> >>>>> On Tue, Jan 5, 2010 at 2:51 PM, Mirco Orlandi <
>> mirco.orlandi_at_gmail.com
>> >>>>> >wrote:
>> >>>>>
>> >>>>> > Bryan,
>> >>>>> > double link solution work well, without additional prefix
>> >>>>> advertising.
>> >>>>> >
>> >>>>> > ...but still work with a single link and additional blackhole
>> route
>> >>>>> > advertising at hub ce. Then we can mantain control of spoke2spoke
>> >>>>> traffic
>> >>>>> > with acl on hub ce wan interface.
>> >>>>> >
>> >>>>> > In double link scenario we have two link used in unidirectional
>> way
>> >>>>> for
>> >>>>> > spoke2spoke traffic; in single link scenario, one link used in
>> >>>>> bidirectional
>> >>>>> > way.
>> >>>>> > I think this is more common hub&spoke scenario. Do you agree?
>> >>>>> >
>> >>>>> > Regards,
>> >>>>> > mirco.
>> >>>>> >
>> >>>>> >
>> >>>>> > On Tue, Jan 5, 2010 at 9:17 PM, Bryan Bartik <
>> bbartik_at_ipexpert.com>
>> >>>>> wrote:
>> >>>>> >
>> >>>>> >> Hub and Spoke VPNs usually require two links between the hub CE
>> and
>> >>>>> PE.
>> >>>>> >> Each
>> >>>>> >> link is in a separate VRF on the PE side. The first VRF imports
>> all
>> >>>>> the
>> >>>>> >> spoke routes and advertise them to the hub CE. The second VRF
>> will
>> >>>>> take
>> >>>>> >> these routes from the CE and advertise them back to the spokes
>> with
>> >>>>> a
>> >>>>> >> different RT. The spoke sites will then import this second RT
>> (not
>> >>>>> the
>> >>>>> >> first). This pulls all traffic from the spokes to the Hub CE and
>> >>>>> back out.
>> >>>>> >>
>> >>>>> >> Remember the goal is to not only get traffic to the Hub PE, but
>> the
>> >>>>> Hub
>> >>>>> >> CE...which is the tricky part. It has nothing to do with split
>> >>>>> horizon,
>> >>>>> >> but
>> >>>>> >> rather the way a router builds the shortest path tree. A shortest
>> >>>>> path
>> >>>>> >> will
>> >>>>> >> never include the same link in two directions without some funky
>> >>>>> >> engineering.
>> >>>>> >>
>> >>>>> >> If you have only have one link between PE and CE, I believe this
>> is
>> >>>>> not a
>> >>>>> >> true hub and spoke and the problem is you are not importing the
>> >>>>> spoke RTs
>> >>>>> >> and at each of the other spokes, only the hub.
>> >>>>> >>
>> >>>>> >> On Tue, Jan 5, 2010 at 1:01 PM, <olukolade_at_gmail.com> wrote:
>> >>>>> >>
>> >>>>> >> > Ignore pls. Been drinking.
>> >>>>> >> > Sent from my BlackBerry. wireless handheld from Glo Mobile.
>> >>>>> >> >
>> >>>>> >> > -----Original Message-----
>> >>>>> >> > From: olukolade_at_gmail.com
>> >>>>> >> > Date: Tue, 5 Jan 2010 19:23:35
>> >>>>> >> > To: jack daniels<jckdaniels12_at_gmail.com>; <
>> >>>>> Charles.Henson_at_regions.com>
>> >>>>> >> > Cc: Cisco certification<ccielab_at_groupstudy.com>; Marko
>> >>>>> Milivojevic<
>> >>>>> >> > markom_at_ipexpert.com>; <nobody_at_groupstudy.com>
>> >>>>> >> > Subject: Re: split horizon
>> >>>>> >> >
>> >>>>> >> > Hi jack,
>> >>>>> >> > CE hub won't be doing the advertisement. It will be done by
>> PE1.
>> >>>>> Don't
>> >>>>> >> > forget PE1 is also running ospf and has all the routes in bgp.
>> So
>> >>>>> routes
>> >>>>> >> > from the other PEs will be tagged with RT 2:2 and exported.
>> This
>> >>>>> will be
>> >>>>> >> > imported on the other PEs where the routes from PE2 will be
>> >>>>> imported by
>> >>>>> >> PE3
>> >>>>> >> > and vice versa. These routes are then redistributed into ospf
>> for
>> >>>>> the
>> >>>>> >> > connected CEs. The CEs will not advertise the routes learnt
>> from
>> >>>>> the PE
>> >>>>> >> back
>> >>>>> >> > to them and there will be no need to do this.
>> >>>>> >> >
>> >>>>> >> > Kolade
>> >>>>> >> > Sent from my BlackBerry. wireless handheld from Glo Mobile.
>> >>>>> >> >
>> >>>>> >> > -----Original Message-----
>> >>>>> >> > From: jack daniels <jckdaniels12_at_gmail.com>
>> >>>>> >> > Date: Wed, 6 Jan 2010 00:06:14
>> >>>>> >> > To: <Charles.Henson_at_regions.com>
>> >>>>> >> > Cc: Cisco certification<ccielab_at_groupstudy.com>; Marko
>> >>>>> Milivojevic<
>> >>>>> >> > markom_at_ipexpert.com>; <nobody_at_groupstudy.com>
>> >>>>> >> > Subject: Re: split horizon
>> >>>>> >> >
>> >>>>> >> > CE (HUB)
>> >>>>> >> > G0/1
>> >>>>> >> > |
>> >>>>> >> > OSPF
>> >>>>> >> > |
>> >>>>> >> > PE1
>> >>>>> >> > |
>> >>>>> >> > MPLS
>> >>>>> CLOUD-----------------------------PE2------OSPF-CE(SPOKE1) (
>> >>>>> >> > 2.2.2.0/24)
>> >>>>> >> >
>> >>>>> >> > |
>> >>>>> >> > |
>> >>>>> >> > |
>> >>>>> >> > PE3
>> >>>>> >> > |
>> >>>>> >> > OSPF
>> >>>>> >> > |
>> >>>>> >> > CE(SPOKE2) (1.1.1.0/24)
>> >>>>> >> >
>> >>>>> >> > IN VRF of customer -
>> >>>>> >> >
>> >>>>> >> > PE3 advertises 1.1.1.0/24 routes with RT1:1 and imports 2:2
>> >>>>> >> >
>> >>>>> >> > PE2 advertises 2.2.2.0/24 routes with RT 1:1 and imports 2:2
>> >>>>> >> >
>> >>>>> >> > PE1 exports routes with RT 2:2 and imports 1:1
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >> > NOW 1.1.1.0/24 is learnt on CE HUB Gi0/1 via OSPF .....
>> >>>>> >> > Will CE HUB advertise 1.1.1.0/24 on Gi0/1 back as it is
>> required
>> >>>>> for
>> >>>>> >> CE
>> >>>>> >> > SPOKE1 for SPOKE to SPOKE reachabilty via HUB?
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >> > On Tue, Jan 5, 2010 at 11:57 PM, <Charles.Henson_at_regions.com>
>> >>>>> wrote:
>> >>>>> >> >
>> >>>>> >> > > Hey Jack,
>> >>>>> >> > > How about a little more details? Configs? Shows?
>> Anything?
>> >>>>> Marko
>> >>>>> >> is
>> >>>>> >> > > correct.
>> >>>>> >> > >
>> >>>>> >> > > Charles Henson
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > > |------------>
>> >>>>> >> > > | From: |
>> >>>>> >> > > |------------>
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>>
>> >----------------------------------------------------------------------------
>> ----------------------------------------------------------------------|
>> >>>>> >> > > |jack daniels <jckdaniels12_at_gmail.com>
>> >>>>> >> > >
>> >>>>> >> > |
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>>
>> >----------------------------------------------------------------------------
>> ----------------------------------------------------------------------|
>> >>>>> >> > > |------------>
>> >>>>> >> > > | To: |
>> >>>>> >> > > |------------>
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>>
>> >----------------------------------------------------------------------------
>> ----------------------------------------------------------------------|
>> >>>>> >> > > |Marko Milivojevic <markom_at_ipexpert.com>
>> >>>>> >> > >
>> >>>>> >> > |
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>>
>> >----------------------------------------------------------------------------
>> ----------------------------------------------------------------------|
>> >>>>> >> > > |------------>
>> >>>>> >> > > | Cc: |
>> >>>>> >> > > |------------>
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>>
>> >----------------------------------------------------------------------------
>> ----------------------------------------------------------------------|
>> >>>>> >> > > |Cisco certification <ccielab_at_groupstudy.com>
>> >>>>> >> > >
>> >>>>> >> > |
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>>
>> >----------------------------------------------------------------------------
>> ----------------------------------------------------------------------|
>> >>>>> >> > > |------------>
>> >>>>> >> > > | Date: |
>> >>>>> >> > > |------------>
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>>
>> >----------------------------------------------------------------------------
>> ----------------------------------------------------------------------|
>> >>>>> >> > > |01/05/2010 12:21 PM
>> >>>>> >> > >
>> >>>>> >> |
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>>
>> >----------------------------------------------------------------------------
>> ----------------------------------------------------------------------|
>> >>>>> >> > > |------------>
>> >>>>> >> > > | Subject: |
>> >>>>> >> > > |------------>
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>>
>> >----------------------------------------------------------------------------
>> ----------------------------------------------------------------------|
>> >>>>> >> > > |Re: split horizon
>> >>>>> >> > >
>> >>>>> >> |
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>>
>> >----------------------------------------------------------------------------
>> ----------------------------------------------------------------------|
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > > I understand that but ,u mean in OSPF
>> >>>>> >> > >
>> >>>>> >> > > IF i recive 1.1.1.0/24 on G0/1 of HUB
>> >>>>> >> > >
>> >>>>> >> > > I'LL advertise 1.1.1.0/24 on Gi0/1 (SAME INTERFACE) of HUB
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > > On Tue, Jan 5, 2010 at 11:44 PM, Marko Milivojevic
>> >>>>> >> > > <markom_at_ipexpert.com>wrote:
>> >>>>> >> > >
>> >>>>> >> > > > On Tue, Jan 5, 2010 at 19:00, jack daniels <
>> >>>>> jckdaniels12_at_gmail.com
>> >>>>> >> >
>> >>>>> >> > > > wrote:
>> >>>>> >> > > > > Hi guys,
>> >>>>> >> > > > >
>> >>>>> >> > > > > I have a scenario where in MPLS VPN - HUB and SPOKE.
>> >>>>> >> > > > >
>> >>>>> >> > > > > CE-PE protocol is OSPF everywhere
>> >>>>> >> > > > >
>> >>>>> >> > > > >
>> >>>>> >> > > > > HUB is recieving routes from one SPOKE on int G0/1 and
>> not
>> >>>>> >> > advertiseing
>> >>>>> >> > > > on
>> >>>>> >> > > > > same (SPLIT horizon).
>> >>>>> >> > > > >
>> >>>>> >> > > > > In ospf how can we overcome such issue.
>> >>>>> >> > > >
>> >>>>> >> > > > OSPF is a link state protocol. It doesn't use split horizon
>> >>>>> (at
>> >>>>> >> least
>> >>>>> >> > > > not within the same area and even in multiarea, the
>> behavior
>> >>>>> is not
>> >>>>> >> > > > called that). You are probably having some other issue...
>> >>>>> >> > > >
>> >>>>> >> > > > --
>> >>>>> >> > > > Marko Milivojevic - CCIE #18427
>> >>>>> >> > > > Senior Technical Instructor - IPexpert
>> >>>>> >> > > >
>> >>>>> >> > > > Mailto: markom_at_ipexpert.com
>> >>>>> >> > > > Telephone: +1.810.326.1444
>> >>>>> >> > > > Fax: +1.810.454.0130
>> >>>>> >> > > > Community: http://www.ipexpert.com/communities
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>> >> > > Blogs and organic groups at http://www.ccie.net
>> >>>>> >> > >
>> >>>>> >> > >
>> >>>>>
>> >>>>>
>> >>_______________________________________________________________________
>> >>>>> >> > > Subscription information may be found at:
>> >>>>> >> > > http://www.groupstudy.com/list/CCIELab.html
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >> > Blogs and organic groups at http://www.ccie.net
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>> >_______________________________________________________________________
>> >>>>> >> > Subscription information may be found at:
>> >>>>> >> > http://www.groupstudy.com/list/CCIELab.html
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >> > Blogs and organic groups at http://www.ccie.net
>> >>>>> >> >
>> >>>>> >>
>> >>>>>
>> >_______________________________________________________________________
>> >>>>> >> > Subscription information may be found at:
>> >>>>> >> > http://www.groupstudy.com/list/CCIELab.html
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >> >
>> >>>>> >>
>> >>>>> >>
>> >>>>> >> --
>> >>>>> >> Bryan Bartik
>> >>>>> >> CCIE #23707 (R&S, SP), CCNP
>> >>>>> >> Sr. Support Engineer - IPexpert, Inc.
>> >>>>> >> URL: http://www.IPexpert.com <http://www.ipexpert.com/>
>> >>>>> >>
>> >>>>> >>
>> >>>>> >> Blogs and organic groups at http://www.ccie.net
>> >>>>> >>
>> >>>>>
>> >>>>>
>> >>_______________________________________________________________________
>> >>>>> >> Subscription information may be found at:
>> >>>>> >> http://www.groupstudy.com/list/CCIELab.html
>> >>>>> >>
>> >>>>> >>
>> >>>>> >>
>> >>>>> >>
>> >>>>> >>
>> >>>>> >>
>> >>>>> >>
>> >>>>> >>
>> >>>>> >
>> >>>>>
>> >>>>>
>> >>>>> --
>> >>>>> Bryan Bartik
>> >>>>> CCIE #23707 (R&S, SP), CCNP
>> >>>>> Sr. Support Engineer - IPexpert, Inc.
>> >>>>> URL: http://www.IPexpert.com <http://www.ipexpert.com/>
>> >>>>>
>> >>>>>
>> >>>>> Blogs and organic groups at http://www.ccie.net
>> >>>>>
>> >>>>>
>> _______________________________________________________________________
>> >>>>> Subscription information may be found at:
>> >>>>> http://www.groupstudy.com/list/CCIELab.html
>>
>>
>> Blogs and organic groups at http://www.ccie.net
>>
>> _______________________________________________________________________
>> Subscription information may be found at:
>> http://www.groupstudy.com/list/CCIELab.html

Blogs and organic groups at http://www.ccie.net
Received on Wed Jan 06 2010 - 18:22:40 ART