Configuring Router Advertisement Settings

Router Advertisement allows IPv6 routers to advertise DNS recursive server addresses to IPv6 hosts. Router Advertisement-based DNS configuration is a useful, optional alternative in networks where an IPv6 host's address is autoconfigured through IPv6 stateless address autoconfiguration, and where the delays in acquiring server addresses and communicating with the servers are critical. Router Advertisement allows the host to acquire the nearest server addresses on every link. Furthermore, it learns these addresses from the same RA message that provides configuration information for the link, thereby avoiding an additional protocol run. This can be beneficial in some mobile environments, such as with Mobile IPv6. SonicWALL’s implementation of IPv6 is full conformable with RFC 4861 in Router and Prefix Discovery.

NOTE: Router Advertisement can only be enabled when interface is under Static mode.

To configure Router Advertisement for an IPv6 interface:

In the Edit Interface window, click on the Router Advertisement tab.

Select the Enable Router Advertisement check box to have make this an advertising interface that will distribute network and prefix information.

Optionally, you can modify the following Router Advertisement settings:

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Router Adv Interval Range - The time interval allowed between sending unsolicited multicast Router Advertisements from the interface, in seconds.

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Link MTU - The recommended MTU for the interface link. A value of 0 means firewall will not advertise link MTU for the link.

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Reachable Time - The time that a node assumes a neighbor is reachable after having received a reachability confirmation. A value of 0 means this parameter is unspecified by this firewall.

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Retrans Time - The time between retransmitted Neighbor Solicitation messages. A value of 0 means this parameter is unspecified by this firewall.

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Current Hop Limit - The default value that should be placed in the Hop Count field of the IP header for outgoing IP packets. A value of 0 means this parameter is unspecified by this firewall.

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Router Lifetime - The lifetime when firewall is accepted as a default router. A value of 0 means that the router is not a default router.

Select the Managed check box to set the managed address configuration flag in the Router Advertisement message. If set, it indicates that IPv6 addresses are available via Dynamic Host Configuration Protocol.

Select the Other Configuration check box to set the Other configuration flag in Router Advertisement message. If set, it indicates that other configuration information is available via Dynamic Host Configuration Protocol.