Multicast Data Fails To Reach Receivers - HP MSR ASM Configuration Manual

Solution
1. Use the display multicast routing-table static command to view the information of static multicast
routes to verify that the static multicast route has been correctly configured and that the route entry
exists in the multicast routing table.
2. Check the type of the next-hop interface of the static multicast route. If the interface is not a
point-to-point interface, be sure to specify the next hop address for the outgoing interface when
you configure the static multicast route.
3. Check that the static multicast route matches the specified routing protocol. If a protocol was
specified in static multicast route configuration, use the display ip routing-table command to verify
that an identical route was added by the protocol.
4. Check that the static multicast route matches the specified routing policy. If a routing policy was
specified when the static multicast route was configured, use the display route-policy command to
check the configured routing policy.

Multicast data fails to reach receivers

Symptom
The multicast data can reach some routers but fails to reach the last-hop router.
Analysis
When a router receives a multicast packet, it decreases the TTL value of the multicast packet by 1
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and recalculates the checksum value. Then, the router forwards the packet to all outgoing interfaces.
If the multicast minimum-ttl command is configured on the outgoing interfaces, the TTL value of the
packet must be greater than the configured minimum TTL value. Otherwise, the packet is discarded.
If you have configured a multicast forwarding boundary by using the multicast boundary command,
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any multicast packet will be kept from crossing the boundary.
Solution
1. Use the display pim routing-table command to verify that the corresponding (S, G) entries exist on
the router. If so, the router has received the multicast data. Otherwise, the router has not received
the data.
2. Use the display multicast minimum-ttl command to check the configured minimum TTL value
required for multicast packets to be forwarded. Use the undo multicast minimum-ttl command on
the concerned interfaces to restore the required minimum TTL value to the system default, or
configure multicast packets to be sent with a higher TTL value from the multicast source.
3. Use the display multicast boundary command to view the multicast boundary information on the
interfaces. Use the multicast boundary command to change the multicast forwarding boundary
setting.
4. In PIM-SM, use the display current-configuration command to check the BSR and RP information.
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