• Enable IGMP on each VLAN when that VLAN has hosts that you want to join multicast groups. Repeat this
action on every switch and router belonging to the VLAN.
• Enable PIM-DM at the global level on the routing switch and on the VLANs where you want to allow routed
multicast traffic.
NOTE:
When you initially enable PIM-DM, it is recommended that you leave the PIM-DM configuration
parameters at their default settings. From the default, you can assess performance and make
configuration changes when needed.
Configuring PIM-DM
PIM-DM requires configuration on both the global level and on the VLAN (interface) level. The recommended
configuration order is:
Procedure
1.
Enable IGMP on all VLANs where hosts may join a multicast group.
2.
Enable the following at the global level:
a.
IP routing
b.
IP multicast routing
c.
Router PIM and any non-default, global PIM settings you want to apply
d.
Router RIP, Router OSPF, and/or a static route
3.
If you selected RIP or OSPF in step 2: enable the same option on each VLAN where you want multicast
routing to operate.
4.
Enable the following in each VLAN context where you want multicast routing to operate:
a.
IP RIP or IP OSPF
b.
IP PIM
c.
Any non-default, VLAN-level IP PIM settings you want to apply
PIM-DM DT
PIM-DM DT is not VLAN specific. PIM-DM DT can be configured on any VLAN to enable PIM-DM DT. For more
information, see Distributed Trunking chapter in the
Management and Configuration Guide
of your switch.
• When PIM-DM DT are enabled, the feature is in place.
• PIM-SM can be configured with DT.
• v1 modules must be disabled prior to PIM-DM DT. Module v1 is available with either feature individually but not
when enabled together. Use the
[no] allow-v1-modules
command to disable V1 modules. If PIM-DM DT
is enabled first, a v1 module will fail.
Chapter 3 PIM-DM (Dense Mode)
75