Mvpn Configuration Guidelines And Restrictions - Cisco 7604 Configuration Manual

Chapter 25 Configuring IPv4 Multicast VPN Support
In the service provider core, PFC3BXL or PFC3B mode hardware acceleration supports multicast traffic
in PIM sparse, PIM bidirectional, and PIM SSM modes. In the service provider core, PFC3BXL or
PFC3B mode hardware acceleration does not support multicast traffic in PIM dense mode.

MVPN Configuration Guidelines and Restrictions

When configuring MVPN, follow these guidelines and restrictions:
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OL-4266-08
Release 12.2(18)SXE and later releases support MVPN when the router is operating in PFC3B mode
or PFC3BXL mode. Supervisor Engine 2 does not support MVPN.
All PE routers in the multicast domain need to be running a Cisco IOS software image that supports
the MVPN feature. There is no requirement for MVPN support on the P and CE routers.
Support for IPv4 multicast traffic must also be enabled on all backbone routers.
The Border Gateway Protocol (BGP) routing protocol must be configured and operational on all
routers supporting multicast traffic. In addition, BGP extended communities must be enabled (using
the neighbor send-community both or neighbor send-community extended command) to support
the use of MDTs in the network.
Only ingress replication is supported when MVPN is configured. If the router is currently
configured for egress replication, it is forced into ingress replication when the first MVRF is
configured.
When the router is acting as a PE, and receives a multicast packet from a customer router with a
time-to-live (TTL) value of 2, it drops the packet instead of encapsulating it and forwarding it across
the MVPN link. Because such packets would normally be dropped by the PE at the other end of the
MVPN link, this does not affect traffic flow.
If the core multicast routing uses SSM, then the data and default multicast distribution tree (MDT)
groups must be configured within the SSM range of IPv4 addresses.
The update source interface for the BGP peerings must be the same for all BGP peerings configured
on the router in order for the default MDT to be configured properly. If you use a loopback address
for BGP peering, then PIM sparse mode must be enabled on the loopback address.
The ip mroute-cache command must be enabled on the loopback interface used as the BGP peering
interface in order for distributed multicast switching to function on the platforms that support it. The
no ip mroute-cache command must not be present on these interfaces.
Data MDTs are not created for VRF PIM dense mode multicast streams because of the flood and
prune nature of dense mode multicast flows and the resulting periodic bring-up and tear-down of
such data MDTs.
Data MDTs are not created for VRF PIM bidirectional mode because source information is not
available.
MVPN does not support multiple BGP peering update sources, and configuring them can break
MVPN RPF checking. The source IPv4 address of the MVPN tunnels is determined by the highest
IPv4 address used for the BGP peering update source. If this IPv4 address is not the IPv4 address
used as the BGP peering address with the remote PE router, MVPN will not function properly.
MDT tunnels do not carry unicast traffic.
Although MVPN uses the infrastructure of MPLS VPN networks, you cannot apply MPLS tags or
labels to multicast traffic over the VPNs.
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
MVPN Configuration Guidelines and Restrictions
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