Re: MPLS VPN Route Target Rewrite

Tom,

As long as you remember that the RD is NOT and does NOT define/identify the
VPN and typically in the real world, they are different to stop this kind of
confusion. Whereas, the route-targets identify the VPN.

On Sun, Jan 30, 2011 at 10:23 AM, Carlos G Mendioroz <tron_at_huapi.ba.ar>wrote:

> Tom,
> RDs make part of the route identifier, i.e., the update object that MP-BGP
> transmits. RTs are communities, i.e., information elements that go with the
> update.
>
> You are seeing the 100:1:172.16.5.0/24 in both R5 and R6, and it has
> the RT 100:55.
>
> Now, at R6, you can see this route with "show ip bgp vpnv4 all" because
> you are asking for ALL vpnv4 routes.
> It is even listed under the 100:1 section, wich is VPN_A RD at R6 (and R5,
> which is generating this route).
>
> But at R6, you are importing only RT 100:1 into VPN_A, and this route
> does not have this RT, so the route does not make it into vrf VPN_A.
>
> Makes sense ?
> Some guys will advise you not to use the same RD at different routers,
> so you will not get this confusing states. In production, I would actually
> agree. But for the IE, I'd prefer to have it very clear how it works.
>
> -Carlos
>
> Tom Kacprzynski @ 30/01/2011 12:49 -0300 dixit:
>
>> Carlos,
>> Thank you for your reply. My configuration is below, but basically i'm
>> trying to take the route 172.16.5.0/24 from VPN_A on R5, rewrite its
>> extended community route tag to 100:55 and have that route-tag imported
>> into
>> VPN_B on R6. I have to say that it does work in terms that only VPN_B sees
>> it, but i don't understand why it shows that route in both BGP VPNv4
>> tables
>> for VPN_A and VPN_B.
>>
>> R6#
>> ip vrf VPN_A
>> rd 100:1
>> route-target export 100:1
>> route-target import 100:1
>> ip vrf VPN_B
>> rd 100:2
>> route-target export 100:2
>> route-target import 100:2
>> * route-target import 100:55*
>>
>> R5#
>> ip vrf VPN_A
>> rd 100:1
>> export map VPN-A-EXPORT
>> route-target export 100:1
>> route-target import 100:1
>> route-target import 100:55
>> ip vrf VPN_B
>> rd 100:2
>> route-target export 100:2
>> route-target import 100:2
>>
>>
>> R5#sh route-map VPN-A-EXPORT
>> route-map VPN-A-EXPORT, permit, sequence 10
>> Match clauses:
>> ip address prefix-lists: LO101
>> Set clauses:
>> extended community RT:100:55
>> Policy routing matches: 0 packets, 0 bytes
>> route-map VPN-A-EXPORT, permit, sequence 100
>> Match clauses:
>> Set clauses:
>> extended community RT:100:1
>> Policy routing matches: 0 packets, 0 bytes
>>
>> Thank you.
>>
>> TK
>>
>>
>> On Sat, Jan 29, 2011 at 11:45 AM, Carlos G Mendioroz <tron_at_huapi.ba.ar
>> >wrote:
>>
>> Sounds like a problem with the import RT for vrf VPN_A ?
>>> The route is there with RT 100:55. What are you importing ?
>>> -Carlos
>>>
>>> Tom Kacprzynski @ 29/01/2011 14:23 -0300 dixit:
>>>
>>> Hello experts,
>>>> Doing a lab wiht MP-BGP and can't seem to figure out how is it possible
>>>> to
>>>> get this output. When I do *show ip bgp vpnv4 vrf VPN_A *I don't see
>>>> 172.16.5.0/24 route, but when i do *show ip bgp vpnv4 all *I see that
>>>> same
>>>> route. Shouldn't both of them show the same information. I this lab
>>>> (INE
>>>> 14.5) I'm asked to rewrite that prefix's route target and export it
>>>> from
>>>> one VRF table to the VPN_A table.
>>>>
>>>> Rack1R6#*show ip bgp vpnv4 vrf VPN_A*
>>>> BGP table version is 41, local router ID is 150.1.6.6
>>>> Status codes: s suppressed, d damped, h history, * valid, > best, i -
>>>> internal,
>>>> r RIB-failure, S Stale
>>>> Origin codes: i - IGP, e - EGP, ? - incomplete
>>>>
>>>> Network Next Hop Metric LocPrf Weight Path
>>>> Route Distinguisher: 100:1 (*default for vrf VPN_A*)
>>>> <----- no 172.16.5.0/24 route (see below)
>>>> *>i155.1.58.0/24 150.1.5.5 0 100 0 ?
>>>> *> 155.1.67.0/24 0.0.0.0 0 32768 ?
>>>> *> 172.16.7.0/24 155.1.67.7 0 32768 ?
>>>>
>>>>
>>>> Rack1R6#*show ip bgp vpnv4 all*
>>>> BGP table version is 41, local router ID is 150.1.6.6
>>>> Status codes: s suppressed, d damped, h history, * valid, > best, i -
>>>> internal,
>>>> r RIB-failure, S Stale
>>>> Origin codes: i - IGP, e - EGP, ? - incomplete
>>>>
>>>> Network Next Hop Metric LocPrf Weight Path
>>>> Route Distinguisher: 100:1 (*default for vrf VPN_A*)
>>>> *>i155.1.58.0/24 150.1.5.5 0 100 0 ?
>>>> *> 155.1.67.0/24 0.0.0.0 0 32768 ?
>>>> **>i172.16.5.0/24 150.1.5.5 0 100 0 ?
>>>> <*---- 172.16.5.0/24
>>>> *> 172.16.7.0/24 155.1.67.7 0 32768 ?
>>>> Route Distinguisher: 100:2 (default for vrf VPN_B)
>>>> *>i155.1.5.0/24 150.1.5.5 0 100 0 ?
>>>> *> 155.1.76.0/24 0.0.0.0 0 32768 ?
>>>> **>i172.16.5.0/24 150.1.5.5 0 100 0 ?**
>>>> <*---- 172.16.5.0/24
>>>> *> 192.168.6.0 0.0.0.0 0 32768 ?
>>>> *> 192.168.7.0 155.1.76.7 0 32768 ?
>>>>
>>>>
>>>>
>>>>
>>>> Rack1R6#*show ip bgp vpnv4 all 172.16.5.0*
>>>> BGP routing table entry for 100:1:172.16.5.0/24, version 31
>>>> Paths: (1 available, best #1, *no table*)
>>>> Not advertised to any peer
>>>> Local
>>>> 150.1.5.5 (metric 66) from 150.1.4.4 (150.1.4.4)
>>>> Origin incomplete, metric 0, localpref 100, valid, internal, best
>>>> Extended Community: RT:100:55
>>>> Originator: 150.1.5.5, Cluster list: 150.1.4.4
>>>> mpls labels in/out nolabel/25
>>>> BGP routing table entry for 100:2:172.16.5.0/24, version 34
>>>> Paths: (1 available, best #1, table *VPN_B*)
>>>> Not advertised to any peer
>>>> Local, imported path from 100:1:172.16.5.0/24
>>>> 150.1.5.5 (metric 66) from 150.1.4.4 (150.1.4.4)
>>>> Origin incomplete, metric 0, localpref 100, valid, internal, best
>>>> Extended Community: RT:100:55
>>>> Originator: 150.1.5.5, Cluster list: 150.1.4.4
>>>> mpls labels in/out nolabel/25
>>>>
>>>>
>>>> Thank you for any help.. i'm really stuck on this and can't figure it
>>>> out.
>>>> I
>>>> fee like i'm missing some piece of information.
>>>>
>>>>
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>>>>
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>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> --
>>> Carlos G Mendioroz <tron_at_huapi.ba.ar> LW7 EQI Argentina
>>>
>>
>>
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>>
>>
> --
> Carlos G Mendioroz <tron_at_huapi.ba.ar> LW7 EQI Argentina
>
>
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> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
>
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