NAME

slattach − attach serial lines as network interfaces

SYNOPSIS

slattach [{+|−}{c|e|i|m mtu|v} ...] tty_name source_address destination_address [baud_rate]

DESCRIPTION

The slattach command is used for assigning the tty line tty_name to a network interface, as well as for defining the network source_address and destination_address values.  The tty_name parameter is the name of the serial line over which the Serial Line Interface Protocol (SLIP) will run; if the tty_name parameter does not begin with /dev/, then /dev/ will be prepended to tty_name.  The optional baud_rate parameter is used to set the speed of the connection.  If not specified, the default value of 9600 will be used. 

Only the super-user may attach (or detach) a network interface. 

The following optional arguments can be used to fine tune how the network interface is to behave:

{+|−}c turns the TCP/IP header compression mode on or off (the default setting is off). 

{+|−}e turns the automatic detection and the use of TCP/IP header compression on or off (the default setting is off).  If the flag +c is given, then this flag (either +e or −e) has no effect.  When the flag +e is given, the SLIP module will not send any compressed TCP/IP headers until it has received and successfully uncompressed a compressed TCP/IP packet. 

{+|−}i turns the suppression of ICMP packets on or off (the default setting is off). 

{+|−}m mtu
sets the maximum transmission unit (“mtu”) of the network interface to mtu (the default “mtu” value is 296).  The maximum allowable value is 8232. 

{+|−}v print or don’t print various messages about the interface as it is being brought up (the default setting is to not print messages). 

To detach a SLIP interface, simply kill the slattach process and then use the following command to remove this Point-to-Point route from the Routing Table:

route delete destination_address gateway_address

EXAMPLES

slattach contty 128.211.8.4 128.211.8.186
slattach +c /dev/contty percival zapranoth 2400

DIAGNOSTICS

The following error messages may occur:

•   The specified interface does not exist. 
•   The requested address is unknown. 
•   A non−privileged user tried to alter the configuration for an interface.

SEE ALSO

netstat(1M), ifconfig(1M), rc2(1M), route(1M), slip(7). 
RFC 1144.

NOTES

If both ends of the connection use the flag +e and if neither end uses +c, then the TCP/IP header compression mode will never get turned on because neither end will take the initiative to send a compressed packet. 

It is suggested that the mtu value for the TCP/IP packet header be 40 plus some power of 2  (for example, 296 = 40 + 2∗∗8).