Troubleshooting guide

3. Troubleshooting Functional Failures During Operation
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possible, address information might not be correctly distributed by RA. Therefore, check whether
the RA functionality is correctly set in the configuration. To carry out the check, do the following:
1. Log in to the Switch.
2. Execute the
show ipv6 routers command to check the RA information for the Switch.
3. If the IPv6 address information has been correctly distributed, the interface might have a
problem with the functionality shown below. That functionality must be checked.
• Filters and QoS functionality
See (7) Checking the filters and QoS configuration information.
(9) Checking the optional license OP-NPAR
If the target interface is a VRF interface and the configuration is present, but the interface is not
displayed by the
show ipv6 interface command, or if in the same situation, the interface is
displayed but the IPv6 address specified in the configuration is not displayed by the same
command, the optional license OP-NPAR might have not been registered or might be invalid. Use
the
show license command to check optional licenses of the Switch. To carry out the check, do
the following:
1. Log in to the Switch.
2. Use the
show license command to check the license software and enabled options.
3. If OP-NPAR is not displayed for the license software, the OP-NPAR license key is not
registered. Register the OP-NPAR license key.
4. If OP-NPAR is displayed for the license software, but OP-NPAR is not displayed for the
enabled options, the hardware configuration of the Switch might not support OP-NPAR.
Check the hardware configuration. For details about the hardware configurations that do not
support OP-NPAR, see the Configuration Guide Vol. 1.
5. If the hardware configuration of the Switch supports OP-NPAR, but OP-NPAR is not
displayed for the enabled options, it is necessary to restart the Switch to enable the optional
license. Use the
reload command to restart the Switch.
6. If OP-NPAR is displayed for the enabled options, see (3) Identifying the range for a failure
(from the Switch).
3.10.2 IPv6 DHCP relay communication problems
There are three probable causes for communication problems on an IPv6 DHCP relay.
1. A configuration related to the IPv6 DHCP relay is changed.
2. The network configuration is changed.
3. The IPv6 DHCP server fails.
For cause 2, check the differences in the network configuration before and after the change to
uncover any cause that could disable communication.
In this subsection, ALAXALA Networks Corporation considers a case to which the cause 1 or 3
applies, assuming that you have checked the client settings. This is a case when, for example, after
the configuration is changed, the IPv6 DHCP server cannot distribute information, or when the
configuration and network configuration are correct, but prefixes (addresses) cannot be assigned
to clients and IP communication fails. The following describes the procedure for isolating the fault
location to identify the cause of the problem.
Use the following flowchart to isolate the fault location to identify the cause of the problem.