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ip6config(8)              BSD System Manager's Manual             ip6config(8)

     ip6config -- Configure IPv6 and 6to4 IPv6 tunnelling

     ip6config [-h] command interface

     The ip6config script can be used to start up or shut down IPv6 on active
     interfaces. It can also be used to configure a 6to4 tunnel and start or
     stop router advertisement.

     When IPv6 is enabled on an interface the protocol is attached to the
     interface, at which point the default settings in the kernel allow it to
     acquire a link-local address and listen for router advertisements.

     6to4 is a mechanism by which your IPv6 address(es) are derived from an
     assigned IPv4 address, and which involves automatic tunnelling to one or
     more remove 6to4 hubs, which will then forward your v6 packets on the
     6bone etc. Replies are routed back to you over IPv4 via (possibly) other
     6to4 capable remote gateways. As such, IPv6-in-IPv4-encapsulated packets
     are accepted from all v4-hosts.

     From your (single) IPv4 address, you get a whole IPv6 /48 network, which
     allows you to split your network in 2^16 subnets, with 2^64 hosts each.
     You need to setup routing for your internal network properly, help is
     provided for setting up the border router here.

     This script takes the burden to calculate your IPv6 address from existing
     IPv4 address and runs the commands to setup (and tear down) automatic
     6to4 IPv6 tunnelling.

     Finally, router advertisement for an internal network can be started and
     stopped. This uses sysctl to set net.inet6.ip6.forwarding and
     net.inet6.ip6.accept_rtadv to the proper values for routing.

     Possible options are:

     -h   Show usage.

     Possible commands are:

     start-v6      Start IPv6 on given interface using default kernel set-
                   tings. Attaches protocol to the interface. If interface is
                   "all", all valid interfaces will be configured.

     stop-v6       Stop IPv6 on given interface. Detaches protocol from the
                   interface. If interface is "all", all valid interfaces will
                   be configured.

     start-stf     Configure 6to4 IPv6. The stf(4) interface is configured,
                   and a default route to a remote 6to4 gateway is estab-
                   lished. In addition, the internal network interface is
                   assigned an address.

     stop-stf      Stops 6to4 IPv6. All addresses are removed from the stf(4)
                   device, and the default route is removed.

     start-rtadvd  Starts router advertizement and IPv6 packet forwarding,
                   turning the machine into a IPv6 router.  rtadvd(8) is
                   invoked with a custom config file created under /var/run.
                   Clients just need to be told to accept router advertize-
                   ments, i.e.  the 'net.inet6.ip6.accept_rtadv' sysctl needs
                   to be set to '1'.  You can arrange that by setting
                   ``ip6mode=autohost'' in /etc/rc.conf.

     stop-rtadvd   Stops router advertizement and IPv6 packet forwarding.
                   rtadvd(8) is stopped, and the rtadvd.conf(5) config file is
                   removed from /var/run.

     Besides IPv4 connectivity, you need support for IPv6 and the stf(4)
     device in your kernel. This is provided beginning with Darwin Kernel Ver-
     sion 6.0.

     No special values are needed in /etc/rc.conf to run this script, but see
     comment on setting up IPv6-clients 'behind' your 6to4 router for the
     rtadvd-start command!

     The default IPv6 configuration for an interface assigns a link-local
     address to it and sets the interface to receive router advertisements.
     No further configuration is necessary for basic functionality.  However,
     various settings can be modified by using sysctl.

     The ip6config script reads its 6to4 configuration from a config file
     named 6to4.conf.  The 6to4.conf file is in perl(1) syntax, and contains
     several variables that can be tuned to adjust your setup.

     in_if         The inside interface. If non-empty, this interface is
                   assigned the IPv6 address 2002:x:x:v6_innernet:hostbits6,
                   see below.  This is only useful on machines that have more
                   than one network interface, e.g. with a modem and a local

     v6_net        The subnet address you want to use on the address of your
                   outbound interface. Defaults to ``1''.

     v6_innernet   The subnet address you want to use on the address of your
                   inbound interface. Defaults to ``2''.

     hostbits6     The lower 64 bits of both the inbound and outbound inter-
                   face's addresses.

     peer          Name of the remote 6to4 server that'll take our IPv6-in-
                   IPv4 encapsulated packets and route them on via IPv6. A
                   special value of ``6to4-anycast'' can be used for the any-
                   cast service defined in RFC 3068.  Other possible values
                   are given in the example config file.

     stf(4), ``6to4 IPv6 Explained'' at http://www.feyrer.de/NetBSD/6to4.html,
     NetBSD IPv6 Documentation at
     http://www.netbsd.org/Documentation/network/ipv6/, RFC 3068.

     The ip6config 6to4 utility and manpage portions were written by Hubert
     Feyrer <hubertATfeyrer.de> for NetBSD.

BSD                              May 21, 2002                              BSD