Multicast VPN QoS

prakashj · ‎08-04-2008

Hi,

How do we configure QoS for MVPN on 7600. IOS is 12.2(33)SRC. There is no support for the command set ip dsp tunnel <value>. Is there any other way.

Regards,

Prakash

sadbulali · ‎08-08-2008

MVPN is a standards-based feature that transmits IPv4 multicast traffic across an MPLS VPN cloud. MVPN on Cisco 7600 series routers uses the existing PFC hardware support for IPv4 multicast traffic to forward multicast traffic over VPNs at wire speeds. MVPN adds support for IPv4 multicast traffic over Layer 3 IPv4 VPNs to the existing IPv4 unicast support.

Giuseppe Larosa · ‎08-09-2008

Hello Prakash,

Cisco MVPN implementation uses multipoint GRE tunnels to forward multicast packets from customer network via provider network.

So for MVPN QoS applies what applies to unicast traffic.

the multicast packet is carried inside a GRE header with source and destination that are PE loopbacks on the provider network.

I'm not sure but the GRE header TOS byte should be a copy of the carried packet's TOS byte.

If so just have in the core links' schedulers classes that classify traffic based on ip dscp or MPLS EXP (match-any)

see

http://www.cisco.com/en/US/docs/routers/7600/ios/12.2SR/configuration/guide/mvpn.html

and for PFC QoS

PFC QoS processes both unicast and multicast traffic.

http://www.cisco.com/en/US/docs/routers/7600/ios/12.2SR/configuration/guide/qos.html#wp1481021

Hope to help

Giuseppe

prakashj · ‎08-10-2008

Thanks Giuseppe...we tried all diffrent configurations to match the DSCP to EXP bit in the egress...but no success...the ingress multicast vpn traffic DSCP always matches to class-default in the egress... :(

Regards,

Prakash

Giuseppe Larosa · ‎08-12-2008

Hello Prakash,

are you using egress multicast replication ?

see this:

Egress mode is not compatible with QoS or SPAN. When QoS is configured, egress replication can result in the incorrect COS or DSCP marking of packets. When SPAN is configured, egress replication can result in multicast packets not being sent to the SPAN destination port. If you are using QoS or SPAN and your switching modules are capable of egress replication, enter the mls ip multicast replication-mode ingress command to force ingress replication.

from

http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SX/configuration/guide/mcastv4.html#wp1076728

Hope to help

Giuseppe

prakashj · ‎08-17-2008

It is working now. The issue was on matching access-list and the order of class-map. On the egress interface it will show as DSCP instead of EXP as multicast is not label switched.

Regards,

Prakash

Giuseppe Larosa · ‎08-17-2008

Hello Prakash,

nice to hear it is working now.

If I correctly understand the issue was at the edge in the service-policy used for marking where you modified an ACL and the order of class-maps within the service-policy.

Best Regards

Giuseppe

prakashj · ‎08-17-2008

Hi Giusseppe,

You are right...actually the customer had the following requirement...

All the multicast traffic should go to scavenger class and remaining traffic should have AF31 till a particular bandwidth has reached and if it exceeds it should be remarked as scavenger traffic.

Actually the mistake what we did was having a standard access-list with multicast as source instead of destination.

Regards,

Prakash