Cisco ASR 9000 Series Software Manual page 46

Understanding Interface Configuration Inheritance
Multicast-Routing Configuration Submode
In Cisco IOS XR software release 3.7.2 and later, basic multicast services start automatically when the multicast
PIE (asr9k-mcast-p.pie) is installed, without any explicit configuration required. The following multicast
services are started automatically:
• MFWD
• MRIB
• PIM
• IGMP
Other multicast services require explicit configuration before they start. For example, to start the MSDP
process, you must enter the router msdp command and explicitly configure it.
When you issue the multicast-routing ipv4 or multicast-routing ipv6 command, all default multicast
components (PIM, IGMP, MLD, MFWD, and MRIB) are automatically started, and the CLI prompt changes
to "config-mcast-ipv4" or "config-mcast-ipv6", indicating that you have entered multicast-routing configuration
submode.
PIM Configuration Submode
When you issue the router pim command, the CLI prompt changes to "config-pim-ipv4," indicating that you
have entered the default pim address-family configuration submode.
To enter pim address-family configuration submode for IPv6, type the address-family ipv6 keyword together
with the router pim command before pressing Enter.
IGMP Configuration Submode
When you issue the router igmp command, the CLI prompt changes to "config-igmp," indicating that you
have entered IGMP configuration submode.
MLD Configuration Submode
When you issue the router mld command, the CLI prompt changes to "config-mld," indicating that you have
entered MLD configuration submode.
MSDP Configuration Submode
When you issue the router msdp command, the CLI prompt changes to "config-msdp," indicating that you
have entered router MSDP configuration submode.
Understanding Interface Configuration Inheritance
Cisco IOS XR Software allows you to configure commands for a large number of interfaces by applying
command configuration within a multicast routing submode that could be inherited by all interfaces. To
Cisco ASR 9000 Series Aggregation Services Router Multicast Configuration Guide, Release 5.1.x
46
Implementing Layer-3 Multicast Routing on Cisco IOS XR Software