xref: /freebsd/sbin/nos-tun/nos-tun.8 (revision e66dbdb6c09a044f96f8fd8edb8e35ac46092b8c)

.\"
.\" ----------------------------------------------------------------------------
.\" "THE BEER-WARE LICENSE" (Revision 42):
.\" <phk@FreeBSD.org> wrote this file.  As long as you retain this notice you
.\" can do whatever you want with this stuff. If we meet some day, and you think
.\" this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
.\" ----------------------------------------------------------------------------
.\"
.\" $Id$
.\"
.Dd April 11, 1998
.Dt NOS-TUN 8
.Os FreeBSD 3.0
.Sh NAME
.Nm nos-tun
.Nd Implement ``nos'' or ``ka9q'' style IP over IP tunnel
.Sh SYNOPSIS
.Nm nos-tun
.Fl t
.Ar tunnel
.Fl s
.Ar source
.Fl d
.Ar destination
.Ar target
.Sh DESCRIPTION
.Nm
is used to establish an
.Em nos
style tunnel, (also known as
.Em ka9q
or
.Em IP-IP
tunnel) using a
.Xr tun 4
kernel interface.
.Pp
.Ar tunnel
is the name of the tunnel device
.Dq /dev/tun0
for example.
.Pp
.Ar source
and
.Ar destination
are the addresses used on the tunnel device.
If you configure the tunnel against a cisco router, use a netmask of
.Dq 255.255.255.252
on the cisco.  This is because the tunnel is a point-to-point interface
in the FreeBSD end, a concept cisco doesn't really implement.
.Pp
.Ar target
is the address of the remote tunnel device, this must match the source
address set on the remote end.
.Sh EXAMPLES
This end, a FreeBSD box on address 192.168.59.34:
.Bd -literal -offset indent 4m
nos-tun -t /dev/tun0 -s 192.168.61.1 -d 192.168.61.2 192.168.56.45
.Ed
.Pp
Remote cisco on address 192.168.56.45:
.Bd -literal -offset indent 4m
interface tunnel 0
ip address 192.168.61.2 255.255.255.252
tunnel mode nos
tunnel destination 192.168.59.34
tunnel source 192.168.56.45
.Ed
.Sh BUGS
We don't allow for setting our source address for multihomed machines.
.Sh AUTHOR
Nickolay N. Dudorov <nnd@itfs.nsk.su> wrote the program,
Poul-Henning Kamp <phk@FreeBSD.org> wrote the man-page.