IFCONFIG(8c,C) AIX TCP/IP User's Guide IFCONFIG(8c,C)
-------------------------------------------------------------------------------
ifconfig
PURPOSE
Configures network interface parameters.
SYNTAX
+----------------+ +---------+ +------------+
ifconfig -- interface --| |--| |--| |--|
+ address_family + + address + + parameters +
DESCRIPTION
The ifconfig command is used to assign an address to a network interface or
configure network interface parameters. The ifconfig command must be used at
boot time to define the network address of each interface present on on a
machine. This is done by placing the ifconfig command in the /etc/ rc.tcpip or
<LOCAL>/rc.tcpip.local files. It may also be used at a later time to redefine
an interface's address or other operating parameters. The interface parameter
is a string of the form name unit, such as tk0.
To configure a point-to-point interface (e.g., vctc), use the following format,
where interface# is the point-to-point interface name followed by a unit
number, such as vctc0:
ifconfig interface# address dest_addr
For the DARPA Internet family, the address and dest_addr are either a host name
data base, /etc/hosts or a DARPA Internet address expressed in the Internet
standard dot notation.
The ifconfig command serves a similar purpose to the netconfig command.
The address family default is DARPA Internet. Currently, AIX does not support
other address families.
PARAMETERS
The following parameters may be set with ifconfig:
up Marks an interface up. This may be used to enable an interface after an
ifconfig down. It happens automatically when setting the first address on
an interface. If the interface is present when previously marked down, the
hardware is re-initialized.
Processed October 29, 1990 IFCONFIG(8c,C) 1
IFCONFIG(8c,C) AIX TCP/IP User's Guide IFCONFIG(8c,C)
down
Marks an interface down. When an interface is marked down, the system does
not attempt to transmit messages through that interface. If possible, the
interface is reset to disable reception as well. This action does not
automatically disable routes using the interface.
arp token
arp ether
Enables the use of the Address Resolution Protocol in mapping between
network level addresses and link level addresses. arp token selects the
Token-Ring address handling scheme. arp ether selects the Ethernet address
handling scheme. When using ifconfig to configure a network interface, you
must choose either arp ether, arp token, or -arp. There is no default.
Note: The syntax for arp has changed since the last version of AIX (1.2).
If you have used the arp option of ifconfig, you probably need to change
the ifconfig command in either the /etc/rc.tcpip file or the
<LOCAL>/rc.tcpip.local file .
-arp
Disables the use of the Address Resolution Protocol.
metric n
Sets the routing metric of the interface to n, (not 0). The routing metric
is used by the routing protocol ("route"). Higher metrics have the effect
of making a route less favorable. Metrics are counted as additional hops
to the destination network or host.
debug
Enables driver dependent debugging code. Usually, this turns on extra
console error logging.
-debug
Disables driver dependent debugging code.
netmask mask
(net only) Specifies how much of the address to reserve for subdividing
networks into sub-networks. The mask includes the network part of the
local address and the subnet part, which is taken from the host field of
the address. The mask can be specified as a single hexadecimal number with
a leading 0x, with a dot notation Internet address or with a pseudo-network
name listed in the network table "networks." The mask contains 1's for the
bit positions in the 32-bit address which are to be used for the network
and subnet parts, and 0's for the host part. The mask should contain at
least the standard network portion, and the subnet field should be
contiguous with the network portion.
broadcast address
(In net only) Specifies the address to use to represent broadcasts to the
network. The default broadcast address is the address with a host part of
all 1's.
Processed October 29, 1990 IFCONFIG(8c,C) 2
IFCONFIG(8c,C) AIX TCP/IP User's Guide IFCONFIG(8c,C)
ieee
Enables the ieee 802 protocol on an Ethernet device.
-ieee
Disables the ieee 802 protocol on an Ethernet device.
trailers
Request 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. On
networks that support the Address Resolution Protocol ("arp"; currently,
only 10M bytes Ethernet), this flag indicates that the system should
request that only systems use trailers when sending to this host.
Similarly, trailer encapsulations will be sent to other hosts that have
made such requests currently used by Internet protocols only.
-trailers
Disables the use of a trailer link level encapsulation.
The ifconfig command displays the current configuration for a network interface
when no optional parameters are supplied. If a protocol family is specified,
ifconfig reports only the details specific to that protocol family.
Only the superuser may modify the configuration of a network interface.
Note: ifconfig interface address sets the interface up.
EXAMPLES
Configure the interface "net0" on the host called "host2".
# /etc/ifconfig net0 host2
#
MESSAGES
Messages are provided indicating the specified interface does not exist, the
requested address is unknown, or the user is not privileged and tried to alter
an interface's configuration.
RELATED INFORMATION
In this book:
"netstat"
"rc.tcpip, rc.tcpip.local"
"netconfig"
Processed October 29, 1990 IFCONFIG(8c,C) 3