Restrictions For Multicast Offload - Cisco ASR 9000 Series System Configuration Manual

Restrictions for Multicast Offload

can be used to classify and allocate a reserved bandwidth for multicast offloaded video streams by shaping
the remaining traffic to 60-70% of the access port interface bandwidth as required.
Due to various scale bottlenecks and for practical reasons, the need for a simple service QoS model as above
the Satellite nV multicast offload solution is recommended to be deployed on a -SE version of the typhoon
line cards.

Restrictions for Multicast Offload

These are the restrictions and considerations of the Multicast offload feature:
• Only Layer-2 multicast offload through IGMP snooping for IPv4 multicast traffic is supported. IPv6
• Endian type mismatching RSPs across the two hosts of the Dual Host system is not supported. IGMP
• Cisco ASR 901 and Cisco ASR 903 satellite devices are not supported. Use of unsupported satellite
• Multicast offload does not support broadcast, multicast router port, or TCN flood event offloading. All
• Only normal Satellite EFPs are considered as OLEs eligible for offload. An OLE consisting of a bundle
• VLAN rewrite support for offloaded replications is not supported. All offloaded replications carry the
• The Cisco ASR9000v and Cisco ASR9000v-V2 hardware can only replicate once per physical access
• Split horizon does not work with offloaded satellite OLEs on a bridge domain. So, multicast source or
• Offload functionality is disabled by default. If it is enabled, there will be a transient downtime including
• While sub-second convergence and fast reroutes are possible for an Layer-2 core failover scenarios (ring
Cisco ASR 9000 Series Aggregation Services Router nV System Configuration Guide, Release 5.3.x
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multicast traffic / MLD snoop and Layer-3 multicast traffic replication offload is not supported.
snoop sync, a pre-requisite for this feature does not function on such hardware.
hardware in an heterogeneous ring, chain, or cascade of satellites may not work as expected as intermediate
unsupported satellite hardware does not participate in multicast packet backbone switching on the ring.
such traffic is replicated on the host.
of satellite ports or pseudo wires and BNG subscribers over satellite ports are not supported as eligible
OLEs for offload. These might fall back to legacy host side replication.
same VLAN tag as the original copy sent by the Host over the dynamically picked master OLE. The
same VLAN rewrite configuration, if required, needs to be added on all the EFPs of a route as any OLE
can be dynamically selected as the master OLE on host. The same applies for any other egress feature
configuration on the OLEs.
port per multicast route (S,G). Therefore, multiple sub-interfaces connected to receivers for same route
in the same bridge domain cannot be offloaded. This is still acceptable for an IPTV scenario, where the
whole port is a trunk to DSLAM devices downstream.
multicast routers (mrouter port) must not be over satellite EFPs within the same bridge domain where
receivers through offloaded satellite EFPs are also present.
impact to traffic for all IGMP snoop routes on the system as the offload mode switches. Similarly, all
routes (including non-offloaded routes) in the system are impacted if offload is disabled on any of the
bridge domains as IGMP snoop moves to non-offload mode.
Note Local replication can co-exist with offloaded replication for same route/bridge
domain/satellite combinations.
break, split brain, core link down and so on), L3 core (over BVI) requires the BVI redundancy state
Configuring Multicast Offload on the Satellite nV System