IPv6 stateless address auto-configuration (SLAAC)

FortiGate can easily obtain an IPv6 address on any given interface using SLAAC (stateless address auto-configuration). SLAAC is designed only for IP assignments and does not provide DNS server addresses to hosts. See RFC 4862 for more information.

Use one of the following options to obtain a DNS server address:

• DHCPv6 stateful server

• SLAAC with DHCPv6 stateless server

In this example, Server-Fgt is connected to Client-Fgt. Server-Fgt has SLAAC enabled, which allows Client-Fgt to automatically obtain an IPv6 address using the auto-configuration IPv6 address option.

To enable IPv6 auto-configuration in the GUI:

1. Configure SLAAC on Server-Fgt:

   1. Go to Network > Interfaces and edit port5.

   2. Configure the following settings:

      IPv6 addressing mode	Manual
      IPv6 Address/Prefix	2001:db8:d0c:1::1/64
      Stateless Address Auto-configuration (SLAAC)	Enable
      IPv6 prefix list	Enable
      IPv6 prefix	2001:db8:d0c:1::/64

   3. Click OK.

2. Configure Client-Fgt to automatically obtain an IPv6 address:

   1. Go to Network > Interfaces and edit port5.

   2. Enable Auto configure IPv6 address. Client-Fgt uses the prefix that it obtains from the Server-Fgt interface, and automatically generates an IPv6 address.

3. Verify that Client-Fgt automatically generated an IPv6 address:

   1. Go to Network > Interfaces and edit port5. The IPv6 Address/Prefix field is populated with an IPv6 address.

To enable IPv6 auto-configuration in the CLI:

1. Configure SLAAC on Server-Fgt:

   config system interface
       edit "port5"
           config ipv6
               set ip6-address 2001:db8:d0c:1::1/64
               set ip6-send-adv enable
               config ip6-prefix-list
                   edit 2001:db8:d0c:1::/64
                   next
               end
           end
       next
   end

2. Configure Client-Fgt to automatically obtain an IPv6 address:

   config system interface
       edit "port5"
           config ipv6
               set autoconf enable
           end
       next
   end
   

3. Verify that Client-Fgt automatically generated an IPv6 address:

   # diagnose ipv6 address list | grep port5
   dev=4 devname=port5 flag= scope=0 prefix=64 addr=2001:db8:d0c:1:20c:29ff:fe4d:f83d preferred=604419 valid=2591619 cstamp=976270 tstamp=979470