6TO4RELAY(1M)6TO4RELAY(1M)NAME6to4relay - administer configuration for 6to4 relay router communica‐
tion
SYNOPSIS
/usr/sbin/6to4relay
/usr/sbin/6to4relay [-e] [-a addr]
/usr/sbin/6to4relay [-d]
/usr/sbin/6to4relay [-h]
DESCRIPTION
The 6to4relay command is used to configure 6to4 relay router communica‐
tion. Relay router communication support is enabled by setting the
value of a variable that stores an IPv4 address within the tun module.
This variable is global to all tunnels and defines the policy for com‐
munication with relay routers. By default, the address is set to
INADDR_ANY (0.0.0.0), and the kernel interprets the value to indicate
that support for relay router communication is disabled. Otherwise,
support is enabled, and the specified address is used as the IPv4 des‐
tination address when packets destined for native IPv6 (non-6to4) hosts
are sent through the 6to4 tunnel interface. The 6to4relay command uses
a project private ioctl to set the variable.
6to4relay used without any options outputs the current, in-kernel, con‐
figuration status. Use the -a option to send packets to a specific
relay router's unicast address instead of the default anycast address.
The address specified with the -a option does not specify the policy
for receiving traffic from relay routers. The source relay router on a
received packet is non-deterministic, since a different relay router
may be chosen for each sending native IPv6 end-point.
Configuration changes made by using the 6to4relay are not persistent
across reboot. The changes will persist in the kernel only until you
take the tunnel down
OPTIONS
The 6to4relay command supports the following options:
-a addr
Use the specified address, addr.
-e
Enable support for relay router. Use -a addr if it is speci‐
fied. Otherwise, use the default anycast address,
192.88.99.1.
-d
Disable support for the relay router.
-h
Help
OPERANDS
The following operands are supported:
addr
A specific relay router's unicast address. addr must be speci‐
fied as a dotted decimal representation of an IPv4 address.
Otherwise, an error will occur, and the command will fail.
EXAMPLES
Example 1 Printing the In-Kernel Configuration Status
Use /usr/sbin/6to4relay without any options to print the in-kernel con‐
figuration status.
example# /usr/sbin/6to4relay
If 6to4 relay router communication is disabled, the administrator will
see the following message:
6to4relay: 6to4 Relay Router communication support is disabled.
If 6to4 router communication is enabled, the user will see this mes‐
sage:
6to4relay: 6to4 Relay Router communication support is enabled.
IPv4 destination address of Relay Router = 192.88.99.1
EXIT STATUS
The following exit values are returned:
0
Successful completion.
>0
An error occurred.
FILES
/usr/sbin/6to4relay
The default installation root
SEE ALSOifconfig(1M), attributes(5)
Huitema, C. RFC 3068, An Anycast Prefix for 6to4 Relay Routers. Network
Working Group. June, 2001.
Carpenter, B. and Moore, K. RFC 3056, Connection of IPv6 Domains via
IPv4 Clouds. Network Working Group. February, 2001.
DIAGNOSTICS
The 6to4relay reports the following messages:
6to4relay: input (0.0.0.0) is not a valid IPv4 unicast address
Example:
The following example provides an incorrect unicast address.
example# 6to4relay-e -a 0.0.0.0
Description:
The address specified with the -a option must be a valid unicast
address.
6to4relay: option requires an argument -a
usage:
6to4relay
6to4relay -e [-a <addr>]
6to4relay-d
6to4relay-h
Example:
The following example does not include an argument for the -a
option.
example# 6to4relay-e -a
Description:
The -a option requires an argument.
usage:
6to4relay
6to4relay -e [-a <addr>]
6to4relay-d
6to4relay-h
Example:
The following example specifies options that are not permitted.
example# 6to4relay-e -d
Description:
The options specified are not permitted. A usage message is output
to the screen.
usage:
6to4relay
6to4relay -e [-a <addr>]
6to4relay-d
6to4relay-h
Example:
The following example specifies the -a option without specifying
the -e option.
example# 6to4relay-a 1.2.3.4
Description:
The -e option is required in conjunction with the -a option. A
usage message is output to the screen.
6to4relay: ioctl (I_STR) : Invalid argument
Example:
The following example specifies an invalid address.
example# 6to4relay-e -a 239.255.255.255
Description:
The address specified with the -a option must not be a class d
addr.
Nov 19, 2002 6TO4RELAY(1M)
