Re: Ping fails across VRF

Bryan,

This in my Topo...

CE---R3---R1----R5----R6----CE

If I look on R1 to see the ldp forwarding table I see...

Rack2R1#sho mpls forwarding-table | inc (155.2.6.6/32|155.2.3.3/32)
16 Untagged 155.2.3.3/32 12288 Se0/1/0 point2point
18 16 155.2.6.6/32 13036 Fa0/0 150.1.15.5
Rack2R1#

and on R5 I see...

Rack2R5#sho mpls forwarding-table | inc (155.2.6.6/32|155.2.3.3/32)
16 Untagged 155.2.6.6/32 8973 Fa0/1 150.1.56.6
18 16 155.2.3.3/32 16955 Fa0/0 150.1.15.1
Rack2R5#

If what I have been reading is correct, then R1 and R5 are sending the mpls
lable as a ipv4 packet to R3 &R6 respectively.
I have my MP-BGP peerings between R3&R6 via the Lo0 interface.
I believe that instead of Untagged in the above output I should be seeing
"Pop Label" that is the PHP process, right?
Then R3 and R6 will untag the packet and direct it to the correct VRF and an
IPv4 packet, Correct?

If the above logic is correct will taking the Lo0 out of my IGP correct this
issue? Or is this some strange IOS bug?

Chris

On Sat, Aug 29, 2009 at 3:06 PM, Bryan Bartik <bbartik_at_ipexpert.com> wrote:

> Chris,
>
> You don't need to enable mpls on a loopback. Just out the loopback in your
> IGP and labels will get advertised. What makes you think PHP is happening to
> seen? If you see a "no-label" instead of "pop-label" in the LFIB, this is
> not PHP. Make sure you have CEF enabled and your LDP peerings are UP
> throughout the cloud. Let me know what you find.
>
> On Sat, Aug 29, 2009 at 3:57 PM, Christopher Copley <
> copley.chris_at_gmail.com> wrote:
>
>> I think I know what is going on....The PHP process is occurring to soon,
>> by
>> one router. I tried to enable mpls ip on the Lo0 interface and get an
>> error...
>>
>> % MPLS not supported on interface Loopback0
>>
>> Is this an IOS version limitation or a default behavior?
>>
>> Thanks,
>> Chris
>>
>> On Sat, Aug 29, 2009 at 2:33 PM, Christopher Copley
>> <copley.chris_at_gmail.com>wrote:
>>
>> > Sorry all pressed send by mistake WAY to early,
>> >
>> > Anyway...
>> >
>> > I have one VPN and at each of the CE routers I can see the routes from
>> each
>> > other across my MPLS backbone. But ping fails across the Core from CE
>> to
>> > CE, but the routes are there and look correct.
>> >
>> > I have MP-BPG between each PE and the router appear in each VPN.
>> >
>> > Any ideas?
>> >
>> > Chris
>> >
>> >
>> > On Sat, Aug 29, 2009 at 2:29 PM, Christopher Copley <
>> > copley.chris_at_gmail.com> wrote:
>> >
>> >> Experts,
>> >>
>> >> I have an interesting problem with my MPLS study. I am new to MPLS
>> and
>> >> MPLS VPNS and I have got to a place where I am stuck.
>>
>>
>> Blogs and organic groups at http://www.ccie.net
>>
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>
>
> --
> Bryan Bartik
> CCIE #23707 (R&S), CCNP
> Sr. Support Engineer - IPexpert, Inc.
> URL: http://www.IPexpert.com

Blogs and organic groups at http://www.ccie.net
Received on Sat Aug 29 2009 - 15:17:05 ART