IPv6 configuration on Mac OS X

Does IPv6 supported on Mac OS X?

Yes. Mac OS X implements its IPv6 functionality from the KAME stack, very likely importing from FreeBSD. The integratee version in Mac OS X 10.5 is:

net.inet6.ip6.kame_version: 20010528/apple-darwin

The basic IPv6 functionality is there, but several newer subprotocols is not integrated into the Mac OS X base system and currently not available via additional/third-party software. IPv6 is installed by default.

How can I enable IPv6 on Mac OS X?

GUI configuration: (Leopard, Tiger is quite similar)

   * Open Network Preferences Pane
   * Select active interface
   * Click 'Advanced' Button
   * in TCP/IP settings set 'Configure IPv6' to 'Automatically'

There is also a CLI interface available, but this isn't recommended.

IPv6 enabled but I cannot access IPv6 websites. What is the problem?

On the Mac OS X, the Safari and Internet Explorer browsers always prefer to use IPv4 over IPv6. On Firefox the behaviour is the same, but with Firefox you can change thisby entering the URL "about:config", then changing the value of "network.dns.disableIPv6" to "false".

How can change the address selection policy?

Apparently there is no address selection implemented RFC 3484. IPv6 is always preferred even in 6to4 and Teredo case.

How can I enable Privacy Extensions?

Privacy addresses are not enabled by default. Their generation and preferred use is activated with a sysctl:

sysctl net.inet6.ip6.use_tempaddr=1

Does DHCPv6 supported on Mac OS X?

Mac OS X does not include DHCPv6 software in the base operating system. The network control does not allow any kind of DHCPv6 configuration for IPv6 addresses or nameserver information, which could be a hidden DHCPv6 client implementation.

However it is possible to compile the WIDE/KAME DHCPv6, as the Mac OS X IPv6/network stack is based on FreeBSD.

PPP configuration on Mac OS X

The IPv6 supported in ppp in the recent Mac OS X. The PPP client is configured and controlled via the GUI network control panel under PPPoE. Configure IPv6 has to be set to Automatically. When dialling with the PPPoE tool (in the menu bar), the PPP daemon pppd automatically tries to negotiate IPv6 while establishing the PPP link (IPv6CP) and successfully creates a link-local address for the PPP interface. The IPv6 stack afterwards receives RAs on the PPP link and configures an global address on the PPP interface.

After connection establishment, the default route (for IPv6) has to be put on the PPP interface (ppp0 in our case):

route add -inet6 default -interface ppp0

IPv6 applications on Mac OS X