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Add a DHCPv6 server

You can configure Sophos Firewall as a DHCP server to dynamically provide IP addresses and network parameters to clients in a network. You can also configure the server to assign static IP addresses mapped to clients' MAC addresses.

To add a DHCPv6 server, go to Network > DHCP, click Add, and click IPv6. You can configure the following settings:

  • Name: The name of your DHCPv6 server.
  • Interface: Interface to use for the DHCP server. The firewall listens for DHCP queries on this interface.

  • Accept client request via relay: The server accepts DHCP requests through a DHCP relay agent from clients belonging to a subnet different from the server's.

    Note

    When you select Accept client request via relay for a DHCPv6 server created on a physical interface with a delegated IPv6 prefix, the DHCPv6 configuration file won't show any changes.

  • Dynamic IP lease: Ranges from which the DHCP server allocates IP addresses to clients.

    • DHCP clients in the server's subnet: The range must belong to the same subnet as the server interface.
    • DHCP clients in a different subnet: The relay agent's interface must belong to the clients' subnet.

  • Static IP DUID mapping: Static DHCP Unique Identifier-to-IP address mappings. The server always assigns the same IP address to the client DUID on the specified host.

  • Preferred time: Time, in minutes, that a valid address keeps the preferred status. When the preferred time expires, the address is given the deprecated status. The preferred time must be less than the valid time.
  • Valid time: Time, in minutes, that an address keeps the valid status. A valid address can be used for new or existing communications.
  • DNS server: Specify the DNS servers you want the clients to contact. To specify Sophos Firewall as the primary and the secondary DNS server, select Use device's DNS settings. Alternatively, you can enter the IP addresses of the DNS servers you want the clients to contact.
  • DHCP options: You can configure specific DHCPv6 options for the DHCP server to provide to clients. See Appendix B – DHCPv6 Options (RFC 3315).

Click Save to save your settings and create the DHCPv6 server.

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