mVPN with BVI interface on core facing

[dgomez2]

Hi experts.

My doubt is so simple, I have a topology like this:

PC1----7600-1----7600-2----ASR9k1----PC2

Considerations:

- Both PCs are in a vrf A, because of that 7600-1 and ASR9k1 are PEs

- ASR9k1 and 7600-1 have a BGP session with VPNv4 and IPv4 MDT AF.

- The interface between PC2 and ASR9k1 is a BVI

- The interface between ASR9k1 and 7600-2 is BVI and SVI respectly.

- All the topology is PIM-SP enable.

- The RP in the VPN network is 7600-1.

- The RP in the CORE network is 7600-1 too.

- The problem is, when I try to send Mcast traffic from PC1 to PC2, these traffic flow.

- When I say "traffic from PC1 to PC2" I want to say Sender=PC1 and Receiver=PC2.

- In the other way (PC2 to PC1), don´t work.

- when we see the status of the register in 7600_1(RP) we can´t see the S,G output.

- When we use subinterfaces or physical interfaces it work excellent.

- When we use BVI in core facing and CU facing with PIM-SM in the global routing table (not VPN), it work too.

Anyone have any idea?

Thanks in advance!

Daniel.

[Peter L]

Hi

What release are you running on the 9k box? Multicast IRB was first supported in 5.1.1.

Supported bridge port types

• Bundles
• Satellites
• EFPs (physical, vlans, etc)
• Pseudowires

Restrictions

• Supported only on Ethernet line cards and enhanced ethernet line cards.
• Support only for IPv4
• Supports IGMP snooping

Multicast IRB

The CE-PE is collapsed into 1 router (IRB) and IGMP snooping is enabled on the BVIs.

BVI type is included in a multicast VRF. After the BVI slot mask is included in the VRF route slot mask, the traffic from the VRF BVI is forwarded to the VPN/ core.

/Peter

[Eddie Chami]

An addition to that, per-von label allocation HAS to be turned on when IRB/VPN. See the following note:

http://www.cisco.com/c/en/us/td/docs/routers/asr9000/software/asr9k_r4-1/interfaces/configuration/guide/hc41asr9kbook/hc41irb.html#wp1030591

Regards

Eddie. 

[dgomez2]

Hi Eddie,

in accord to your recommendation, I try to change the allocate label mode to per-vrf and the result is the same :(

Any other idea my friend?

Thanks in advance!!!

Daniel.

[Aleksandar Vidakovic]

hi Daniel,

Eddie's recommendation was generic for MPLS VPN with IRB. You know that in the mVPN implementation you are trying to configure we don't use MPLS to forward multicast.

Can you confirm that this solution works when the interface on asr9001 towards 7600-2 is L3 physical (sub)interface and the interface towards PC2 remains a BVI?

Did you check for any packet drops at NP in the non-working scenario?

/Aleksandar

[dgomez2]

Hi Alek, thanks for your comments.

Yes, I confirm that, when I use physical and subinterfaces L3 between ASR9k1 and 7600_2, the topology works! keeping the interface towards PC2  in BVI.

Let me share with you some outputs with the change of the topology putting the interface from ASR9k1 like subinterface:

RP/0/RSP0/CPU0:ASR9K-1#sh run int te0/2/0/0.22
Sat Jul 18 01:55:18.321 UTC
interface TenGigE0/2/0/0.22
ipv4 address 10.2.3.1 255.255.255.0
encapsulation dot1q 22

ASR9k1:

RP/0/RSP0/CPU0:ASR9K-2#sh mrib vrf prueba-ldp route 239.224.0.7
Sat Jul 18 01:52:56.015 UTC

IP Multicast Routing Information Base
Entry flags: L - Domain-Local Source, E - External Source to the Domain,
C - Directly-Connected Check, S - Signal, IA - Inherit Accept,
IF - Inherit From, D - Drop, ME - MDT Encap, EID - Encap ID,
MD - MDT Decap, MT - MDT Threshold Crossed, MH - MDT interface handle
CD - Conditional Decap, MPLS - MPLS Decap, EX - Extranet
MoFE - MoFRR Enabled, MoFS - MoFRR State, MoFP - MoFRR Primary
MoFB - MoFRR Backup, RPFID - RPF ID Set, X - VXLAN
Interface flags: F - Forward, A - Accept, IC - Internal Copy,
NS - Negate Signal, DP - Don't Preserve, SP - Signal Present,
II - Internal Interest, ID - Internal Disinterest, LI - Local Interest,
LD - Local Disinterest, DI - Decapsulation Interface
EI - Encapsulation Interface, MI - MDT Interface, LVIF - MPLS Encap,
EX - Extranet, A2 - Secondary Accept, MT - MDT Threshold Crossed,
MA - Data MDT Assigned, LMI - mLDP MDT Interface, TMI - P2MP-TE MDT Interface
IRMI - IR MDT Interface

(10.10.11.5,239.224.0.7) RPF nbr: 10.10.11.5 Flags: L RPF
Up: 01:31:51
Incoming Interface List
BVI2 Flags: A, Up: 01:31:51

7600_1:

7606-1#sh ip mroute vrf prueba-ldp 239.224.0.7
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,
L - Local, P - Pruned, R - RP-bit set, F - Register flag,
T - SPT-bit set, J - Join SPT, M - MSDP created entry, E - Extranet,
X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement,
U - URD, I - Received Source Specific Host Report,
Z - Multicast Tunnel, z - MDT-data group sender,
Y - Joined MDT-data group, y - Sending to MDT-data group,
G - Received BGP C-Mroute, g - Sent BGP C-Mroute,
N - Received BGP Shared-Tree Prune, n - BGP C-Mroute suppressed,
Q - Received BGP S-A Route, q - Sent BGP S-A Route,
V - RD & Vector, v - Vector, p - PIM Joins on route
Outgoing interface flags: H - Hardware switched, A - Assert winner, p - PIM Join
Timers: Uptime/Expires
Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 239.224.0.7), 01:32:27/stopped, RP 102.102.102.102, flags: SJC
Incoming interface: Tunnel2, RPF nbr 4.4.4.4
Outgoing interface list:
GigabitEthernet3/20, Forward/Sparse, 01:32:27/00:02:12

(10.10.11.5, 239.224.0.7), 00:03:54/00:02:05, flags: JT
Incoming interface: Tunnel2, RPF nbr 4.4.4.4
Outgoing interface list:
GigabitEthernet3/20, Forward/Sparse, 00:03:54/00:02:12

With this outputs the traffic flow successfully.

Regards,

Daniel

[Aleksandar Vidakovic]

Hi Daniel,

thanks for running the additional test. Can you check in pim traces whether the asr9k is generating the join on BVI1. If yes, then check the NP counters for any drops that match the rate of hellos. since you are using 5.3.3, you can run the "sh controller np capture" (see https://supportforums.cisco.com/document/12927596/asr9000xr-troubleshooting-packet-drops-drops-np-microcode)

if that doesn't help, we may be in a better position to help you if you would open a TAC SR.

regards,

/Aleksandar

[dgomez2]

Hi Alek, thanks again.

At this moment I don´t have access to the devices to do this test. As soon as I have access again, I will probe your idea.

Thanks a lot.

Daniel

[dgomez2]

Hi Peter, thanks for your answer.

The version of IOS is 5.3.3.

I can see all the correct structures about the traffic of mcast (S , G) (* , G) outgoing and ingoing interfaces and the groups join in the DR.

The problem is register don´t flow to the RP like if don´t be PIM between 7600_2 and ASR9k1 but, there is PIM between them, because session is establish in the VRF level.

Regards.

[dgomez2]

For update the case, both RP (in vrf A and default) is in ASR9k1.

My mistake :(

Currently I have the lab active, this are the outputs.

I use the group: 239.224.0.6; sender: ASR9k1. Receiver:7600_1.

output ASR9k1:

RP/0/RSP0/CPU0:ASR9K-2#sh mrib vrf prueba-ldp route 239.224.0.6
Fri Jul 17 23:15:11.553 UTC

IP Multicast Routing Information Base
Entry flags: L - Domain-Local Source, E - External Source to the Domain,
C - Directly-Connected Check, S - Signal, IA - Inherit Accept,
IF - Inherit From, D - Drop, ME - MDT Encap, EID - Encap ID,
MD - MDT Decap, MT - MDT Threshold Crossed, MH - MDT interface handle
CD - Conditional Decap, MPLS - MPLS Decap, EX - Extranet
MoFE - MoFRR Enabled, MoFS - MoFRR State, MoFP - MoFRR Primary
MoFB - MoFRR Backup, RPFID - RPF ID Set, X - VXLAN
Interface flags: F - Forward, A - Accept, IC - Internal Copy,
NS - Negate Signal, DP - Don't Preserve, SP - Signal Present,
II - Internal Interest, ID - Internal Disinterest, LI - Local Interest,
LD - Local Disinterest, DI - Decapsulation Interface
EI - Encapsulation Interface, MI - MDT Interface, LVIF - MPLS Encap,
EX - Extranet, A2 - Secondary Accept, MT - MDT Threshold Crossed,
MA - Data MDT Assigned, LMI - mLDP MDT Interface, TMI - P2MP-TE MDT Interface
IRMI - IR MDT Interface

(*,239.224.0.6) RPF nbr: 102.102.102.102 Flags: C RPF
Up: 00:04:12
Incoming Interface List
Decapstunnel2 Flags: A, Up: 00:04:12
Outgoing Interface List
mdtprueba-ldp Flags: F NS MI, Up: 00:04:12

(10.10.11.5,239.224.0.6) RPF nbr: 10.10.11.5 Flags: L RPF
Up: 00:05:55
Incoming Interface List
BVI2 Flags: A, Up: 00:05:55
Outgoing Interface List
mdtprueba-ldp Flags: F NS MI, Up: 00:04:12

output 7600_1:

7606-1#sh ip mroute vrf prueba-ldp 239.224.0.6
IP Multicast Routing Table
Flags: D - Dense, S - Sparse, B - Bidir Group, s - SSM Group, C - Connected,
L - Local, P - Pruned, R - RP-bit set, F - Register flag,
T - SPT-bit set, J - Join SPT, M - MSDP created entry, E - Extranet,
X - Proxy Join Timer Running, A - Candidate for MSDP Advertisement,
U - URD, I - Received Source Specific Host Report,
Z - Multicast Tunnel, z - MDT-data group sender,
Y - Joined MDT-data group, y - Sending to MDT-data group,
G - Received BGP C-Mroute, g - Sent BGP C-Mroute,
N - Received BGP Shared-Tree Prune, n - BGP C-Mroute suppressed,
Q - Received BGP S-A Route, q - Sent BGP S-A Route,
V - RD & Vector, v - Vector, p - PIM Joins on route
Outgoing interface flags: H - Hardware switched, A - Assert winner, p - PIM Join
Timers: Uptime/Expires
Interface state: Interface, Next-Hop or VCD, State/Mode

(*, 239.224.0.6), 00:00:47/00:02:57, RP 102.102.102.102, flags: SJC
Incoming interface: Tunnel2, RPF nbr 4.4.4.4
Outgoing interface list:
GigabitEthernet3/20, Forward/Sparse, 00:00:47/00:02:57

In this moment the traffic is flow right now but, 7600_1 don´t receive the register from ASR9k1 to build the path.

Regards,

Daniel.