[apple/network_cmds.git] / ip6conf.tproj / ip6config.8

.\"     $NetBSD: 6to4.8,v 1.5 2001/12/03 19:03:21 wiz Exp $
.Dd May 21, 2002
.Dt ip6config 8
.Os
.Sh NAME
.Nm ip6config
.Nd Configure IPv6 and 6to4 IPv6 tunnelling
.Sh SYNOPSIS
.Nm
.Op Fl h
.Ar command interface
.Sh DESCRIPTION
The
.Nm
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.
.Pp
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.
.Pp
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.
.Pp
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.
.Pp
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.
.Pp
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.
.Pp
Possible options are:
.Bl -tag -width xxx
.It Fl h
Show usage.
.El
.Pp
Possible commands are:
.Bl -tag -width start-rtadvd
.It Sy start-v6
Start IPv6 on given interface using default kernel settings. Attaches
protocol to the interface. If interface is "all", all valid interfaces
will be configured.
.It Sy stop-v6
Stop IPv6 on given interface. Detaches protocol from the interface. If 
interface is "all", all valid interfaces will be configured.
.It Sy start-stf
Configure 6to4 IPv6. The
.Xr 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.
.It Sy stop-stf
Stops 6to4 IPv6. All addresses are removed from the
.Xr stf 4
device, and the default route is removed.
.It Sy start-rtadvd
Starts router advertizement and IPv6 packet forwarding,
turning the machine into a IPv6 router.
.Xr rtadvd 8
is invoked with a custom config file created under
.Pa /var/run .
Clients just need to be told to accept router advertizements, i.e.
the
.Sq net.inet6.ip6.accept_rtadv
sysctl needs to be set to
.Sq 1 .
You can arrange that by setting
.Dq ip6mode=autohost
in
.Pa /etc/rc.conf .
.It Sy stop-rtadvd
Stops router advertizement and IPv6 packet forwarding.
.Xr rtadvd 8
is stopped, and the
.Xr rtadvd.conf 5
config file is removed from
.Pa /var/run .
.El
.Sh REQUIREMENTS
Besides IPv4 connectivity, you need support for IPv6 and the
.Xr stf 4
device in your kernel. This is provided beginning with Darwin 
Kernel Version 6.0.
.Pp
No special values are needed in
.Pa /etc/rc.conf
to run this script, but see comment on setting up IPv6-clients
.Sq behind
your 6to4 router for the
.Sy rtadvd-start
command!
.Sh CONFIGURATION
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.
.Pp
The
.Nm
script reads its 6to4 configuration from a config file named
.Pa 6to4.conf .
The
.Pa 6to4.conf
file is in
.Xr perl 1
syntax, and contains several
variables that can be tuned to adjust your setup.
.Bl -tag -width start-rtadvd
.It Sy 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 ethernet.
.It Sy v6_net
The subnet address you want to use on the address of
your outbound interface. Defaults to
.Dq 1 .
.It Sy v6_innernet
The subnet address you want to use on the address of
your inbound interface. Defaults to
.Dq 2 .
.It Sy hostbits6
The lower 64 bits of both the inbound and outbound interface's
addresses.
.It Sy 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
.Dq 6to4-anycast
can be used for the anycast service defined in RFC 3068.
Other possible values are given in the example config file.
.El
.Sh SEE ALSO
.Xr stf 4 ,
.Dq 6to4 IPv6 Explained
at
.Pa http://www.feyrer.de/NetBSD/6to4.html ,
.Nx
IPv6 Documentation at
.Pa http://www.netbsd.org/Documentation/network/ipv6/ ,
RFC 3068.
.Sh HISTORY
The
.Nm
6to4 utility and manpage portions were written by
Hubert Feyrer <hubert@feyrer.de> for NetBSD.
Commit	Line	Data
7ba0088d A	1	.\" $NetBSD: 6to4.8,v 1.5 2001/12/03 19:03:21 wiz Exp $
	2	.Dd May 21, 2002
	3	.Dt ip6config 8
	4	.Os
	5	.Sh NAME
	6	.Nm ip6config
	7	.Nd Configure IPv6 and 6to4 IPv6 tunnelling
	8	.Sh SYNOPSIS
	9	.Nm
	10	.Op Fl h
	11	.Ar command interface
	12	.Sh DESCRIPTION
	13	The
	14	.Nm
	15	script can be used to start up or shut down IPv6 on active interfaces. It
	16	can also be used to configure a 6to4 tunnel and start or stop router
	17	advertisement.
	18	.Pp
	19	When IPv6 is enabled on an interface the protocol is attached to the
	20	interface, at which point the default settings in the kernel allow it
	21	to acquire a link-local address and listen for router advertisements.
	22	.Pp
	23	6to4 is a mechanism by which your IPv6 address(es) are derived from an
	24	assigned IPv4 address, and which involves automatic tunnelling to one or
	25	more remove 6to4 hubs, which will then forward your v6 packets on the
	26	6bone etc. Replies are routed back to you over IPv4 via (possibly) other
	27	6to4 capable remote gateways. As such, IPv6-in-IPv4-encapsulated
	28	packets are accepted from all v4-hosts.
	29	.Pp
	30	From your (single) IPv4 address, you get a whole IPv6 /48 network,
	31	which allows you to split your network in 2^16 subnets, with 2^64
	32	hosts each. You need to setup routing for your internal network
	33	properly, help is provided for setting up the border router here.
	34	.Pp
	35	This script takes the burden to calculate your IPv6 address from
	36	existing IPv4 address and runs the commands to setup (and tear down)
	37	automatic 6to4 IPv6 tunnelling.
	38	.Pp
	39	Finally, router advertisement for an internal network can be started
	40	and stopped. This uses sysctl to set net.inet6.ip6.forwarding and
	41	net.inet6.ip6.accept_rtadv to the proper values for routing.
	42	.Pp
	43	Possible options are:
	44	.Bl -tag -width xxx
	45	.It Fl h
	46	Show usage.
	47	.El
	48	.Pp
	49	Possible commands are:
	50	.Bl -tag -width start-rtadvd
	51	.It Sy start-v6
	52	Start IPv6 on given interface using default kernel settings. Attaches
	53	protocol to the interface. If interface is "all", all valid interfaces
	54	will be configured.
	55	.It Sy stop-v6
	56	Stop IPv6 on given interface. Detaches protocol from the interface. If
	57	interface is "all", all valid interfaces will be configured.
	58	.It Sy start-stf
	59	Configure 6to4 IPv6. The
	60	.Xr stf 4
	61	interface is configured, and a default route to a remote 6to4
	62	gateway is established. In addition, the internal
	63	network interface is assigned an address.
	64	.It Sy stop-stf
65	Stops 6to4 IPv6. All addresses are removed from the
66	.Xr stf 4
67	device, and the default route is removed.
68	.It Sy start-rtadvd
69	Starts router advertizement and IPv6 packet forwarding,
70	turning the machine into a IPv6 router.
71	.Xr rtadvd 8
72	is invoked with a custom config file created under
73	.Pa /var/run .
74	Clients just need to be told to accept router advertizements, i.e.
75	the
76	.Sq net.inet6.ip6.accept_rtadv
77	sysctl needs to be set to
78	.Sq 1 .
79	You can arrange that by setting
80	.Dq ip6mode=autohost
81	in
82	.Pa /etc/rc.conf .
83	.It Sy stop-rtadvd
84	Stops router advertizement and IPv6 packet forwarding.
85	.Xr rtadvd 8
86	is stopped, and the
87	.Xr rtadvd.conf 5
88	config file is removed from
89	.Pa /var/run .
90	.El
91	.Sh REQUIREMENTS
92	Besides IPv4 connectivity, you need support for IPv6 and the
93	.Xr stf 4
94	device in your kernel. This is provided beginning with Darwin
95	Kernel Version 6.0.
96	.Pp
97	No special values are needed in
98	.Pa /etc/rc.conf
99	to run this script, but see comment on setting up IPv6-clients
100	.Sq behind
101	your 6to4 router for the
102	.Sy rtadvd-start
103	command!
104	.Sh CONFIGURATION
105	The default IPv6 configuration for an interface assigns a link-local
106	address to it and sets the interface to receive router advertisements.
107	No further configuration is necessary for basic functionality.
108	However, various settings can be modified by using sysctl.
109	.Pp
110	The
111	.Nm
112	script reads its 6to4 configuration from a config file named
113	.Pa 6to4.conf .
114	The
115	.Pa 6to4.conf
116	file is in
117	.Xr perl 1
118	syntax, and contains several
119	variables that can be tuned to adjust your setup.
120	.Bl -tag -width start-rtadvd
121	.It Sy in_if
122	The inside interface. If non-empty, this interface is
123	assigned the IPv6 address
124	2002:x:x:v6_innernet:hostbits6, see below.
125	This is only useful on machines that
126	have more than one network interface, e.g. with a modem and a
127	local ethernet.
128	.It Sy v6_net
129	The subnet address you want to use on the address of
130	your outbound interface. Defaults to
131	.Dq 1 .
132	.It Sy v6_innernet
133	The subnet address you want to use on the address of
134	your inbound interface. Defaults to
135	.Dq 2 .
136	.It Sy hostbits6
137	The lower 64 bits of both the inbound and outbound interface's
138	addresses.
139	.It Sy peer
140	Name of the remote 6to4 server that'll take our
141	IPv6-in-IPv4 encapsulated packets and route them on
142	via IPv6. A special value of
143	.Dq 6to4-anycast
144	can be used for the anycast service defined in RFC 3068.
145	Other possible values are given in the example config file.
146	.El
147	.Sh SEE ALSO
148	.Xr stf 4 ,
149	.Dq 6to4 IPv6 Explained
150	at
151	.Pa http://www.feyrer.de/NetBSD/6to4.html ,
152	.Nx
153	IPv6 Documentation at
154	.Pa http://www.netbsd.org/Documentation/network/ipv6/ ,
155	RFC 3068.
156	.Sh HISTORY
157	The
158	.Nm
159	6to4 utility and manpage portions were written by
160	Hubert Feyrer <hubert@feyrer.de> for NetBSD.