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Add an IPv6 router advertisement

Router advertisements include information about the method to use for address assignment, for example prefixes, hop limit value, and flag status. The device advertises information about various interfaces and internet parameters either periodically or in response to the RS message, informing all the nodes on the network about any address modifications.

  1. Go to Network > IPv6 router advertisement and click Add.
  2. Select an interface. You can choose any IPv6-enabled physical interface, LAG, VLAN, or bridge interface.

  3. Specify the settings.

    Option Description
    Min advertisement interval Minimum time, in seconds, between two consecutive unsolicited router advertisement messages sent to the clients.
    Max advertisement interval Maximum time, in seconds, between two consecutive unsolicited router advertisement messages sent to the clients.
    Note: If the maximum interval is nine seconds or more, the minimum interval must be 75% of the maximum interval.
    Managed flag When turned on, clients obtain IPv6 addresses from the DHCPv6 server.
    Note: Use this option only if a DHCPv6 server is available.
    Other flag When turned on, clients obtain other network parameters such as DNS server, domain name, NIS, NISP, SIP, SNTP, and BCMS servers from the DHCPv6 server.
    Default gateway Use the firewall as the default gateway for communication with the client. When turned on, specify the time, in seconds, to be used for router advertisement.

  4. Create a prefix advertisement configuration. The prefix advertisement includes zero or more prefix options containing information that the default gateway advertises. This information is used by stateless address auto-configuration to automatically generate a global IPv6 address.

    Option Description
    Prefix/64 The first 64 bits of the IPv6 address. The interface uses prefix information from the router advertisement message to determine the last 64 bits (interface identifier) of its 128-bit IPv6 address. The first 64 bits specify the network, while the remaining specify a particular address in the network.
    On-link When turned on, the devices with IPv6 addresses that are within this prefix are reachable on the subnet without a need of a router.
    Autonomous When turned on, the global IPv6 address is automatically generated by appending the 64-bit interface identifier to the prefix advertised. Only prefixes that have this option turned on will receive an IPv6 address through stateless address auto-configuration.
    Preferred lifetime Time, in minutes, for a valid address to remain in the preferred state. On expiry, the preferred address is deprecated. However, the address can continue to be used as the source address for an existing communication. The IPv6 address will continue to remain in the preferred state as long as it is refreshed by prefixes in the router advertisement (or other means) or is renewed by DHCPv6.
    Valid lifetime Time, in minutes, for an address to remain in the valid state. Until the time expires, the prefix is considered to be on-link and auto-configured addresses using the prefix can be used. On expiry, the IPv6 address becomes invalid and cannot be used to send or receive traffic.
    Note: The value must be greater than or equal to the value of the preferred lifetime.

  5. Specify the advanced settings: These settings allow devices on the same interface to discover each other and respective link-layer addresses, to find gateway routers, and to maintain reachability information.

    Option Description
    Link MTU MTU (Maximum Transmission Unit) value in bytes. It's the largest packet size that a network can transmit. Packets larger than the specified value are divided into smaller packets before they are sent. When set to zero, the information will not be advertised by the interface.
    Reachable time Time, in seconds, that the client will use to assume a neighbor is reachable after having received a reachability confirmation message.
    Retransmit time Time, in seconds, that the client will use to determine how long it should wait before retransmitting neighbor solicitation messages.
    Hop limit Maximum number of hops for a packet. The hop value is decremented by each router along the route. On reaching zero, the packet is destroyed

  6. Click Save.