Configuring Pim Snooping - HP FlexNetwork 7500 Series Configuration Manual

Each PIM router in the VLAN, whether interested in the multicast data or not, can receive all
multicast data and all PIM messages except PIM hello messages.
•
When the Layer 2 switch runs both IGMP snooping and PIM snooping, it performs the following
actions:
a. Examines whether a PIM router is interested in the multicast data addressed to a multicast
group according to the received PIM messages that the router send.
b. Adds only the ports that connect to the router and are interested in the data to a PIM
snooping routing entry.
c. Forwards PIM messages and multicast data to only the routers that are interested in the
data, which saves network bandwidth.
For more information about IGMP snooping and the router port, see
PIM snooping can run in PIM-SM and PIM-SSM networks. Do not configure PIM snooping in
PIM-DM or BIDIR-PIM networks. For more information about PIM, see

Configuring PIM snooping

IMPORTANT:
• Do not configure PIM snooping in secondary VLANs because PIM snooping does not take effect
in secondary VLANs. For more information about secondary VLANs, see Layer 2—LAN
Switching Configuration Guide.
• Make sure the IP packet length of join/prune messages is less than the MTU of receiver-side PIM
interfaces that connect to PIM snooping devices. Otherwise, multicast data might not be
correctly forwarded. The IP packet length of join/prune messages is the packet length of
join/prune messages plus the IP header length. To set the maximum size of join/prune
messages, use the jp-pkt-size command. To set the MTU for an Ethernet interface, use the mtu
command. For more information about the command, see Interface Command Reference.
To configure PIM snooping for a VLAN, you must enable IGMP snooping globally on the Layer 2
device, and then enable IGMP snooping and PIM snooping for the VLAN.
After you enable PIM snooping for a VLAN, PIM snooping works only on the member interfaces of
the VLAN.
To configure PIM snooping:
Step
Enter system view.
1.
Enable IGMP snooping
2.
globally and enter
IGMP-snooping view.
Return to system view.
3.
Enter VLAN view.
4.
Enable IGMP snooping for
5.
the VLAN.
Enable PIM snooping for
6.
the VLAN.
(Optional.) Set the aging
7.
time for global neighbor
ports on the new active
MPU after an
active/standby switchover.
Command
system-view
igmp-snooping
quit
vlan vlan-id
igmp-snooping enable
pim-snooping enable
pim-snooping
graceful-restart
neighbor-aging-time interval
40
"Configuring IGMP
"Configuring PIM."
Remarks
N/A
By default, IGMP snooping is
disabled.
N/A
N/A
By default, IGMP snooping is
disabled in a VLAN.
By default, PIM snooping is disabled
in a VLAN.
The default setting is 105 seconds.
A global neighbor port is a Layer 2
aggregate interface that acts as a
neighbor port.
snooping."