Updated: 2021/Apr/14


SLATTACH(8)                 System Manager's Manual                SLATTACH(8)

NAME
     slattach - attach serial lines as network interfaces

SYNOPSIS
     slattach [-Hhlmn] [-s baudrate] [-t ldisc] ttyname

DESCRIPTION
     slattach is used to assign a tty line to a network interface which uses
     asynchronous serial lines.

     Currently the slattach command is used to attach sl(4) interfaces.  These
     interfaces have to be created using the ifconfig(8).  The resulting
     point-to-point link is not a broadcast interface and normally has a
     netmask of 255.255.255.255.  create subcommand before the slattach
     command.  The network source and destination addresses and other
     interface parameters are configured via ifconfig(8).

     The following operands are supported by slattach:

     -H            Turn on DTR/CTS flow control.  By default, no flow control
                   is done.

     -h            Turn on RTS/CTS flow control.  By default, no flow control
                   is done.

     -l            Turn on the CLOCAL flag, making it possible to run SLIP on
                   a cable without modem control signals (e.g. DTR, DSR, DCD).

     -m            Maintain modem control signals after closing the line.
                   Specifically, this disables HUPCL.

     -n            Don't detach from invoking tty.

     -s baudrate   Specifies the speed of the connection.  If not specified,
                   the default of 9600 is used.

     -t ldisc      Specifies the line discipline to use for the tty.
                   Supported line disciplines are "slip" (creates a sl(4)
                   instance).  If this option is not specified, the default is
                   "slip".  This option is retained for backwards
                   compatibility with existing scripts.

     ttyname       Specifies the name of the tty device.  ttyname should be a
                   string of the form `ttyXX', or `/dev/ttyXX'.

     Only the super-user may attach a network interface.

     To detach the interface, use "ifconfig interface-name down" after killing
     off the slattach process.  Interface-name is the name that is shown by
     netstat(1).

EXAMPLES
     Lock, initialize, and attach a line (on both sides):
           cu -t -F [hard|soft] -l /dev/dty00
           ifconfig sl0 create
           slattach -l -t slip /dev/dty00
     On the local side:
           ifconfig sl0 inet 10.0.0.2 10.0.0.1 netmask 255.255.255.255
     On the remote side:
           ifconfig sl0 inet 10.0.0.1 10.0.0.2 netmask 255.255.255.255

DIAGNOSTICS
     Messages indicating that the specified interface is not configured or
     created, the requested address is unknown, or that the user is not
     privileged but tried to alter an interface's configuration.

SEE ALSO
     netstat(1), daemon(3), netintro(4), sl(4), ifconfig(8), rc(8),
     sliplogin(8), slstats(8)

HISTORY
     The slattach command appeared in 4.3BSD.

BUGS
     There is no way to specify the interface name (sl%d etc.) to be attached
     by the slattach command.  There is no way to see which interface is
     assigned to the specified tty by the slattach command, either.

     It would be better if the network interfaces were created by the slattach
     command rather than by using the ifconfig(8) create subcommand before the
     slattach command.

NetBSD 9.99                    January 18, 2020                    NetBSD 9.99