134
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
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,
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.