Troubleshooting guide

3. Troubleshooting Functional Failures During Operation
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3.9 Communication failures in the IPv4 multicast routing functionality
This section describes actions to be taken when an IPv4 multicast communication failure occurs
on the Switch.
3.9.1 Communication is not possible on the IPv4 PIM-SM networks
If multicast forwarding is not possible in an IPv4 PIM-SM network configuration, isolate the cause
of the problem according to the failure analysis method described below.
The following figure shows an example of an IPv4 PIM-SM network.
Figure 3-10: Example of an IPv4 PIM-SM network
Notes:
• BSR: The router that distributes rendezvous point information. (For details, see the
Configuration Guide.)
• Rendezvous point router: The router that forwards packets to the multicast receivers if
the destination of the packets has not been determined. (For details, see the
Configuration Guide.)
•
first-hop-router: The router that is connected directly to the multicast sender
•
last-hop-router: The router that is connected directly to the multicast receivers
(1) Items checked in common
The following table shows the items checked in common for all the Switches in an IPv4 PIM-SM
network configuration.
Table 3-23: Items checked in common
No. Items to check and commands Action
1 Make sure that the setting for using the multicast
functionality (
ip multicast routing) exists in the
configuration.
show running-config
If the setting for using the multicast functionality does
not exist, modify the configuration.
2 For AX6700S, AX6600S, or AX6300S series
switches, make sure that the multicast protocol used in
the configuration is PIM-SM.
(
ip multicast protocol pim-sm is specified or no
command is specified)
show running-config
If a protocol other than PIM-SM is specified for the
multicast protocol, modify the configuration.
In addition, if no multicast protocol is specified in the
configuration, PIM-SM is specified for the multicast
protocol to be used.