NAME

SYNOPSIS

DESCRIPTION

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. In a separate step, router advertisement for the inside network can be started and stopped.

Possible options are:

-n

Do not. Only print the commands that would be run, but do not execute them.

-v

Verbose operation. Print the commands that are about to be run, before running them. Displays some additional information.

-h

Show usage.

Possible commands are:

start

Same as stf-start.

stop

Same as stf-stop.

stf-start

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

stf-stop

Stops 6to4 IPv6. All addresses are removed from the stf(4) device, and the default route is removed. If in_if is set, the 6to4 addresses are removed from that interface too.

rtadvd-start

Starts router advertizement and IPv6 packet forwarding, turning the machine into a IPv6 router. Clients just need to be told to accept router advertizements, i.e. the `net.inet6.ip6.accept_rtadv' sysctl needs to be set to `1'. On NetBSD, you can arrange that by setting ``ip6mode=autohost'' in /etc/rc.conf.

rtadvd-stop

Stops router advertizement and IPv6 packet forwarding. rtadvd(8) is stopped.

REQUIREMENTS

Make sure you have the following options in your kernel config file:

options         INET            # IP + ICMP + TCP + UDP
options         INET6           # IPV6
pseudo-device   stf     1       # 6to4 IPv6 over IPv4 encapsulation

In systems that run past-1.5, you will have to explicitly create an stf(4) device after compiling it in the kernel. You do this by running the following command before calling the hf6to4 script:

ifconfig stf0 create

net_interfaces="stf0"
ifconfig_stf0="create"

See also the comment on setting up IPv6-clients `behind' your 6to4 router for the rtadvd-start command!

CONFIGURATION

out_if

The outbound interface that has a valid IPv4 address assigned, that can be used to derive the IPv6 addresses from. Usually ``ppp0'' for a modem setup, or your ethernet interface if you have IPv4 connectivity via LAN. This can't be empty, and is assigned the IPv6 address 2002:x:x:v6_net:hostbits6, see below.

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 interfaces, e.g. with a modem and a local ethernet.

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 interface'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 anycast service defined in RFC 3068. Other possible values are given in the example config file.

remoteadr4, remoteadr6

If the peer variable is set to the relay router's name, DNS lookups for A and AAAA records will be made to determine its IPv4 and IPv6 address. To avoid these lookups, the variables remoteadr4 and remoteadr6 can be set to strings containing the numerical IPv4 and IPv6 numbers directly.

EXAMPLES

( /usr/pkg/sbin/hf6to4 stf-stop
  /usr/pkg/sbin/hf6to4 stf-start
  /usr/pkg/sbin/hf6to4 rtadvd-stop
  /usr/pkg/sbin/hf6to4 rtadvd-start ) &

To shut down properly, put this into /etc/ppp/ip-down:

/usr/pkg/sbin/hf6to4 stf-stop
/usr/pkg/sbin/hf6to4 rtadvd-stop

SEE ALSO

HISTORY