IFCONFIG(8C)
NAME
ifconfig − configure network interface parameters
USAGE
/etc/ifconfig interface [address] [parameters]
DESCRIPTION
Ifconfig assigns an address to a network interface and/or configures network interface parameters. It must be used at boot time to define the network address of each interface present on a machine. It may also be used at a later time to redefine an interface’s address. The interface parameter is a string of the form name unit. The address is either one of the host names listed in /etc/hosts, or a DARPA Internet address expressed in the Internet standard “dot” notation.
OPTIONS
If invoked with no options, ifconfig displays the current configuration for the specified interface. (Only the super-user may modify the configuration of a network interface.)
The following parameters may be set with ifconfig:
up Mark an interface “up.”
down Mark an interface “down.” When an interface is “down,” the system will not attempt to transmit messages through that interface.
trailers (Not supported on DOMAIN/IX.) Enable the use of a “trailer” link level encapsulation when sending (default). If a network interface supports trailers, the system will, when possible, encapsulate outgoing messages in a manner which minimizes the number of memory to memory copy operations performed by the receiver.
−trailers Disable the use of a “trailer” link level encapsulation. This option is always enabled on DOMAIN/IX systems.
arp Enable the use of the Address Resolution Protocol in mapping between network level addresses and link level addresses (default). This option is always enabled on DOMAIN/IX systems.
−arp (Illegal on DOMAIN/IX.) Disable the use of the Address Resolution Protocol.
EXAMPLE
The following example demonstrates a typical use of ifconfig on DOMAIN/IX systems, returning the state of interface dr0. % /etc/ifconfig dr0 dr0: 192.9.10.10 flags=63<UP,BROADCAST,NOTRAILERS,RUNNING>
DIAGNOSTICS
Ifconfig may return messages indicating the specified interface does not exist, the requested address is unknown, or that an unprivileged user tried to alter an interface’s configuration.