R3166-R3206-HP High-End Firewalls Network Management Configuration Guide-6PW101

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Analysis
• If the multicast static route is not configured or updated correctly to match the current network
conditions, the route entry and the configuration information of multicast static routes do not exist in
the multicast routing table.
• If a better route is found, the multicast static route may also fail.
Solution
1. In the configuration, you can use the display multicast routing-table static config command to view
the detailed configuration information of multicast static routes to verify that the multicast static
route has been correctly configured and the route entry exists.
2. In the configuration, you can use the display multicast routing-table static command to view the
information of multicast static routes to verify that the multicast static route has been correctly
configured and the route entry exists in the multicast routing table.
3. Check the next hop interface type of the multicast static route. If the interface is not a point-to-point
interface, be sure to specify the next hop address to configure the outgoing interface when you
configure the multicast static route.
4. Check that the multicast static route matches the specified routing protocol. If a protocol was
specified in multicast static route configuration, enter the display ip routing-table command to
check if an identical route was added by the protocol.
5. Check that the multicast static route matches the specified routing policy. If a routing policy was
specified when the multicast static route was configured, enter 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 decrements the TTL value of the multicast packet by 1
and recalculates the checksum value. The router then 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 will be
discarded.
• If a multicast forwarding boundary has been configured through the multicast boundary command,
any multicast packet will be kept from crossing the boundary.
Solution
1. Use the display pim routing-table command to check whether 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. Enter 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.