Setting or changing the neighbor discovery retransmit timer


ipv6 nd ra NS-interval <1000–4294967295|unspecified>

ipv6 nd ra NS-interval

no ipv6 nd ra NS-interval

Used on VLAN interfaces to advertise the period (retransmit timer) in milliseconds between ND solicitations sent by a host for an unresolved destination, or between DAD neighbor solicitation requests. Increasing this setting is indicated where neighbor solicitation retries or failures are occurring, or in a "slow" (WAN) network.

The no form returns the setting to its default.



An advertised setting in this range replaces the corresponding, locally configured setting in hosts on the VLAN.


Sets the retransmit timer value in RAs to zero, which causes the hosts on the VLAN to use their own locally configured NS-interval settings instead of using the value received in the RAs.

Default: unspecified (0) ; Range: 1000–4294967295 ms


This is the retransmit timer advertised as a host-specific variable. It is separate from the retransmit timer used by the routing switch for its own ND solicitations (ipv6 nd NS-interval).

If multiple routers on the same VLAN are configured to advertise an NS-interval (retransmit time), all such routers should use the same NS-interval setting.

The default NS-interval setting for IPv6 host operation on devices is 1000 ms. When the above command is used with the unspecified option to configure RAs, host devices configured by using the RA maintain their preconfigured NS-interval settings.