NEC IP8800/S6700, IP8800/S6600, IP8800/S3600, IP8800/S2400 manual IPv6 Network Communication Failure

3. Troubleshooting Functional Failures in Operation

3.9IPv6 Network Communication Failure

3.9.1Communication Is Disabled or Is Disconnected

There are three possible causes that result in communication failure on the IPv6 network using this system.

1.Configuration on IPv6 communication has changed

2.Network configuration has changed

3.Network component failures

For 1 and 2 above, check for the differences in the configuration and network configuration provided before and after the change. Check for any difference disabling communication.

This section describes procedure to identify the failed part and to isolate the problem, mainly for the cases of "IPv6 communication is disabled although the configuration and network configuration are correct." and "IPv6 communication had been normally running but it is disabled now." as described in 3 above.

To locate the faulty part and cause, follow the flow below.

Figure 3-13: Failure Analysis Procedure When IPv6 Communication Disabled

<IPv6 communication disabled>

Verify if there is an occurrence of line failure using the show

logging command.

No physical failure

message exists.

Check the Up/Down status of the interface using the show ipv6 interface command.

Identify the extent of failure using the

ping ipv6 command.

A physical failure message exists.

see the manual "Message Log Reference"and

perform the action described in [Action]

associated with each log message.

Go to "3.4 Network Interface

Communication Failure."

Communication between the
	Communication between the
neighboring host and router	remote host and router is
is disabled.	disabled.
		Unicast communication

			The route
Verify the status of				Verify the route
		Solved
address resolution			information using the		information
					exists.
using the show ipv6			show ipv6 route
neighbors command.			command.
	Unresolve
				No route information exists or the
				next hop address is invalid.

Verify RA address

distribution.

Distributed Not distributed

Verify the IP network of
	Analyze the failure on each	Verify the filter	Verify the RA
remote system. Otherwise, go
	routing protocol. (RIPng,	settings.	settings.
to "3.4 Network Interface
	BGP4+, etc.)
Communication Failure."

71