term% cat index.txt 6IN4(8) System Manager's Manual 6IN4(8)
NAME
6in4, ayiya - configure and run automatic or manual tunnel of IPv6
through IPv4
SYNOPSIS
ip/6in4 [ -ag ] [ -x netmtpt ] [ -o outnetmtpt ] [ local6[/mask] [ re‐
mote4 [ remote6 ] ] ]
ip/ayiya [ -g ] [ -x netmtpt ] [ -k secret ] local6[/mask] remote4 re‐
mote6
DESCRIPTION
6in4 sets up and maintains a 6to4 tunnel of IPv6 traffic through an
IPv4 connection. Ayiya is similar, but uses the UDP based Anything In
Anything protocol to tunnel IPv6 traffic.
Local6 and mask define the IPv6 address and subnet of the near end of
the tunnel (mask defaults to for a single-host tunnel). If local6 is
missing or it defaults to
2002:aabb:ccdd::1/48
where aa, bb, cc and dd are the hexadecimal equivalents of the bytes
a.b.c.d in this host's primary IPv4 address.
Remote4 is the IPv4 address of the far end of the tunnel (must be given
explicitly for a configured tunnel, or defaults to the anycast address
192.88.99.1 for 6to4).
Remote6 is the IPv6 address of the far end of the tunnel (used as the
point-to-point destination for routing, and defaults to a link-local
address constructed from remote4).
The program forks a pair of background processes to copy packets to and
from the tunnel.
Options are:
-a for 6in4, permit any remote IPv4 address as the far end of a
tunnel. This is likely to be useful for the server side of a
tunnel.
-g use the tunnel as the default route for global IPv6 addresses
-x use the network mounted at netmtpt instead of for binding the
tunnel interface and sending/receiving IPv4 packets.
-o for 6in4, use outnetmtpt for the IPv4 packets but bind the IPv6
interface on or netmtpt when specified by a previous -x option.
-k for ayiya, use the shared secret key secret to authenticate mes‐
sages on the tunnel.
EXAMPLES
If your primary IPv4 address is public, you can start a 6to4 tunnel
simply with
ip/6in4 -g
Similarly, you can start a server for 6to4 tunnels with
ip/6in4 -ag
If you use a tunnel broker at address configured to give you a subnet
with address you can start the tunnel with
ip/6in4 -g 2001:1122:3344:5566::/64 5.6.7.8
FILES
/net/ipmux
access to IPv6-in-IPv4 packets
/net/ipifc
packet interface to IPv6 network
SEE ALSO
bridge(3), ipmux in ip(3), linklocal in ipconfig(8)
/lib/rfc/rfc3056
/lib/rfc/rfc3068
http://tools.ietf.org/id/draft-massar-v6ops-ayiya-02.txt
BUGS
Needs a kernel with an ipmux driver.
The tunnel client filters addresses fairly conservatively in both di‐
rections. However it's not watertight, and may be flakey in other ways
so don't put too much trust in it.
6IN4(8)