IGMP Statistics
Use the show ip igmp interface command to display statistics, including hardware
multicast packet replication configuration, for an IP interface stacked over port 8. For
more information, see “Monitoring IGMP” on page 59 in “Configuring IGMP” on page 41.
Blocking and Limiting Multicast Traffic
You can either block mroute creation, limit the multicast bandwidth admitted on an
outgoing interface, or limit outgoing interface creation on a port.
Blocking Mroutes
By default, when an interface that is configured with one or more multicast protocols
(for example, PIM or IGMP) receives multicast traffic, even when the scope of that traffic
exceeds link-local, the virtual router creates an mroute. You can use the ip
block-multicast-sources command to block all multicast traffic with a scope larger than
link-local (for example, global) and prevent mroute creation under these conditions.
NOTE: Issuing this command does not affect reception of link-local multicast packets.
ip block-multicast-sources
• Use to prevent mroute creation by blocking multicast traffic that has a scope larger
than link-local (for example, global).
• Example
host1(config-if)#ip block-multicast-sources
• Use the no version to restore the default behavior of creating mroutes on received
multicast packets.
• See ip block-multicast-sources.
Limiting Interface Admission Bandwidth
Interface-level multicast admission control is performed when an OIF on the interface
is added to the mroute for a given (S,G) multicast data stream and the multicast
bandwidth map contains a set admission-bandwidth action for that (S,G).
When enabled, the admission-bandwidth for a particular (S,G) is read from the multicast
bandwidth map and recorded in the mroute when the (S,G) mroute is created. When an
OIF is subsequently added to the mroute, the OIF is blocked from forwarding data if the
additional bandwidth contributed by the (S,G) would exceed the admission-bandwidth
limit for the interface.
CAUTION: Before you can limit interface-level admission bandwidth, you must first
create a bandwidth map. See “Defining a Multicast Bandwidth Map” on page 10 for
details.
25Copyright © 2010, Juniper Networks, Inc.
Chapter 1: Configuring IPv4 Multicast
To Next Page
Loading...