Configuring Dad - HP 2520-8 Configuration Manual

If an address is configured while DAD is disabled, the address is assumed to
be unique and is assigned to the interface. If you want to verify the uniqueness
of an address configured while DAD was disabled, re-enable DAD and then
either delete and reconfigure the address, or reboot the switch.

Configuring DAD

Syntax: ipv6 nd dad-attempts < 0 - 600 >
This command is executed at the global config level, and
configures the number of neighbor solicitations to send when
performing duplicate address detection for a unicast address
configured on a VLAN interface.
< 0 - 600 >: The number of consecutive neighbor solicitation
messages sent for DAD inquiries on an interface. Setting this
value to 0 disables DAD on the interface. Disabling DAD
bypasses checks for uniqueness on newly configured
addresses. If a reboot is performed while DAD is disabled, the
duplicate address check is not performed on any IPv6
addresses configured on the switch.
Default: 3 (enabled); Range: 0 - 600 (0 = disabled)
The no form of the command restores the default setting (3).
Syntax: ipv6 nd ns-interval < milliseconds >
Used on VLAN interfaces to reconfigure the neighbor discovery
time in milliseconds between DAD neighbor solicitations sent
for an unresolved destination, or between duplicate address
detection neighbor solicitation requests. Increasing this
setting is indicated where neighbor solicitation retries or
failures are occurring, or in a "slow" (WAN) network.
This value can be configured in a router advertisement to help
ensure that all hosts on a VLAN are using the same retransmit
interval for neighbor discovery. Refer to "Neighbor Discovery
(ND)" on page 1-12.
To view the current setting, use show ipv6 nd.
Range: 1000 - 3600000 ms; Default: 1000 ms.
IPv6 Addressing Configuration
Duplicate Address Detection (DAD)
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