ifconfig(8)ifconfig(8)NAMEifconfig - Configures or displays network interface parameters
SYNOPSIS
For the AF_INET address family, use the following syntax:
/usr/sbin/ifconfig interface_id [address_family] [address[/bitmask]
[dest_address]] [parameters]
For the AF_INET6 address family, use the following syntax:
/usr/sbin/ifconfig interface_id address_family [[ip6prefix]
address[/bitmask] [dest_address]] [parameters]
For displaying interface information, use the following syntaxes:
/usr/sbin/ifconfig -a [-d] [-u] [-v] [address_family]
/usr/sbin/ifconfig -l [-d] [-u] [-v] [address_family]
/usr/sbin/ifconfig [-v] interface-id [address_family]
The ifconfig command assigns and displays an address to a network
interface, and configures network interface parameters.
OPTIONS
Displays information about all interfaces that are configured on a sys‐
tem. Displays information about interfaces that are down only. Dis‐
plays interface names only that are configured on a system. Displays
information about interfaces that are up only. Displays verbose infor‐
mation about interfaces, such as hardware addresses and IPv6 timers.
DESCRIPTION
You use the ifconfig command at boot time to define the network address
of each interface. You can also use the ifconfig command at other
times to display all interfaces that are configured on a system, to
redefine the address of an interface, or to set other operating parame‐
ters.
Note
If you want to redefine the address or the netmask of an interface, use
the SysMan Menu utility. Otherwise, any daemons currently running will
use the old address and netmask, and will fail. The SysMan Menu util‐
ity makes the necessary changes and restarts the network services.
The ifconfig command can modify most of the operating parameters asso‐
ciated with network interfaces, including some low-level parameters,
such as the speed (10, 100, or 1000 Mb/s) and mode (half-duplex or
full-duplex) parameters. However, to set other low-level parameters,
such as the media type (AUI, BNC, UTP, or Fiber) or IEEE 802.3u autone‐
gotiation, you must use the lan_config command or possibly a console
firmware command. See lan_config(8) for more information about chang‐
ing these low-level parameters, and viewing their current values.
Any user can query the status of a network interface; only the supe‐
ruser can modify the configuration of network interfaces.
You specify an interface with the ifconfig interface_id syntax. (See
your hardware documentation for information on obtaining an interface
ID.)
If you specify only an interface_id, the ifconfig command displays the
current configuration for the specified network interface only.
If a protocol family is specified by the address_family parameter,
ifconfig reports only the configuration details specific to that proto‐
col family. The following table lists valid values for address_family:
Address Family Value
AF_INET inet
AF_INET6 inet6
When changing an interface configuration, if the address family is not
AF_INET, you must specify an address family, which may alter the inter‐
pretation of any parameters that follow. You must specify an address
family because an interface can receive transmissions in different pro‐
tocols, each of which may require a separate naming scheme.
The address argument is the network address of the interface being con‐
figured. For the AF_INET address family, the address argument is
either a hostname or an Internet address in the standard dotted-decimal
notation with or without the optional Classless Inter-Domain Routing
(CIDR) bitmask (/bitmask). If using the bitmask argument, do not use
the netmask parameter.
For the AF_INET6 address family, the address argument is either a host‐
name or the 128-bit Internet Protocol Version 6 (IPv6) address, as fol‐
lows:
x:x:x:x:x:x:x:x
In this format, each x is the hexadecimal value of a 16-bit piece of
the address. An IPv6 address typically consists of a 64-bit prefix
followed by a 64-bit interface identifier. See the Network Administra‐
tion: Connections manual for more information on IPv6 addresses.
The ip6prefix argument, when configuring an address on the interface,
specifies that the address argument is an IPv6 prefix and that the
interface identifier is to be appended to it to create a 128-bit IPv6
address.
The interface identifier uniquely identifies an interface on a subnet,
and is typically the interface's link-layer address. According to RFC
2373, most prefixes are required to have 64-bit interface identifiers.
For 48-bit MAC addresses, the interface identifier is created by
inserting the hexadecimal values of 0xFF and 0xFE in the middle of the
address and inverting the universal/local bit (bit 7) in the resulting
64-bit address. For example, the 48-bit MAC address 0:0:f8:23:10:f3
becomes the 64-bit interface identifier 2:0:f8:ff:fe:23:10:f3.
The destination address (dest_address) argument specifies the address
of the correspondent on the remote end of a point-to-point link.
Parameters
Closes all TCP connections associated with a network address. Use this
parameter when removing aliases or deleting network addresses. This
prevents users from experiencing a hanging connection when the network
address is deleted. Creates or modifies a set of redundant adapters
(NetRAIN). The ifconfig interface-id parameter must be a NetRAIN vir‐
tual interface name of the form nrx, where x is the unit number (Valid
unit numbers are 0 to nr_maxdev-1. See sys_attrs_netrain(5) for a
description of nr_maxdev and other netrain subsystem attributes. You
can adjust this limit by using dxkerneltuner or the sysconfig command).
If the NetRAIN virtual interface does not exist, it is created.
You can also specify multiple interface-id parameters when cre‐
ating a NetRAIN set. The interface-id specified must represent
adapters of the same type connected to the same LAN segment.
You can also modify an existing NetRAIN set by adding one inter‐
face-id at a time. The interface-id specified must represent an
adapter of the same type and connected to the same LAN segment
as other adapters in the NetRAIN set.
See the Network Administration: Connections manual for complete
information on configuring a NetRAIN interface. [AF_INET only]
Establishes an additional network address for this interface.
This can be useful when changing network numbers and you want to
continue to accept packets addressed to the old interface. This
alias is in effect only until the system is rebooted. To estab‐
lish this alias automatically each time the system is booted,
edit the inet.local file and add the ifconfig alias entries to
it.
If you do not specify a bitmask or netmask with an alias
address, the default netmask is based on the alias address's
network class.
If you are using the optional bitmask argument, do not use the
netmask argument.
This parameter has the following restrictions: You can specify
only one alias alias_address parameter for each ifconfig command
line. You cannot specify an alias and a primary address on the
same command line. [AF_INET only] Removes the network address
specified. This can be used either if you incorrectly specified
an alias or if an alias is no longer needed. The -alias parame‐
ter functions in the same manner as the delete parameter.
[AF_INET only] Establishes a range of additional network
addresses for this interface. The range can be either a comma-
separated list or a hyphenated list, and is inclusive. You can
also specify the optional CIDR bitmask (/bitmask) argument at
the end of the list. Do not use a comma-separated list and a
hyphenated list for a range. See the "Examples" section for
valid examples of the aliaslist parameter.
If you do not specify a netmask with the alias list, the default
netmask is based on the alias address's network class. [AF_INET
only] Removes a range of network addresses for this interface.
This can be useful when deleting network numbers and you want to
keep the primary interface address. The alias list rules are
the same as for the aliaslist parameter. Enables the reception
of all multicast packets. Disables the reception of all multi‐
cast packets. [AF_INET6 only] Marks the address as being of
type Anycast. Enables the use of the Address Resolution Proto‐
col (ARP) in mapping between network-level IPv4 addresses and
link-level addresses. This parameter is on by default. Dis‐
ables the use of the ARP. Use of this parameter is not recom‐
mended. See arp(8) for more information. Specifies the address
to use to represent broadcasts to the network. The default
broadcast address is the address with a host part consisting of
all 1s (ones). Note that the computation of the host part is
dependent on netmask (see the description of the netmask parame‐
ter). Enables driver-dependent debug code. This might turn on
extra console error logging. (See your hardware documentation
for further information.) Disables driver-dependent debug code.
Removes the network address specified. This would be used if
you incorrectly specified an alias, or if it was no longer
needed. If you have incorrectly set an NS address having the
side effect of specifying the host portion, removing all NS
addresses will allow you to respecify the host portion.
Note
Be careful when you use this parameter. If you either specify
the network address before the delete parameter or specify no
network address after the delete parameter, all IPv4 and IPv6
network addresses for the interface and IPv6 routes are deleted.
IPv4 routes are not deleted. Marks an interface as not working
(down), which keeps the system from trying to transmit messages
through that interface. If possible, the ifconfig command also
resets the interface to disable reception of messages. Routes
that use the interface, however, are not automatically disabled.
Enables access filtering on the interface. Reads the /etc/ifac‐
cess.conf file and constructs an interface access filter based
on entries in the file. Interface access filtering provides a
mechanism for detecting and preventing IP spoofing attacks. (See
CERT Advisory CA-95:01). The source addresses of IP input pack‐
ets are checked against access filter entries; packets receive
the action associated with the first matching entry. The fol‐
lowing actions are valid: permit, deny, or denylog; the final
filter entry is a default permit all. See ifaccess.conf(4) for
more information.
Use the netstat(1) command to display the current access filters
for the interface. Disables access filtering on the interface.
[AF_INET6 only] Specifies the number of consecutive Neighbor
Solicitation messages that your system transmits while it per‐
forms Duplicate Address Detection on a tentative address.
[AF_INET6 only] Sets the default number of hops to be included
in transmitted unicast IP packets. [AF_INET6 only] Overrides
that default interface ID, which depends on the underlying link
type (for example, Ethernet, FDDI, and Token Ring), and speci‐
fies id as the interface ID. For example, if your system has
the Ethernet hardware address 08-00-2b-2a-1e-d3, the following
command generates the inet6 link-local address
fe80::a00:2bff:fe2a:1ed3 for the interface:
ifconfig ln0 ipv6
On the same system, the following command generates the inet6
interface ID abcd:1234 for the interface:
ifconfig ln0 ip6interfaceid ::abcd:1234 ipv6 [AF_INET6 only]
Alters the maximum transfer unit (MTU) for messages that your
system transmits on the link. [AF_INET6 only] Disables Neigh‐
bor Unreachability Detection (NUD) on the interface. [AF_INET6
only] Sets the time, in milliseconds, that your system consid‐
ers a neighbor is reachable after your system receives a reacha‐
bility confirmation message. [AF_INET6 only] Sets the time
interval, in milliseconds, between Neighbor Solicitation mes‐
sages to a neighbor. Specifies an Internet host willing to
receive IP packets encapsulating packets bound for a remote net‐
work. [AF_INET only] Alters the size of the maximum transfer
unit (MTU) for messages that your system transmits. It might be
necessary to reduce the MTU size so that bridges connecting
token rings can transfer frames without error. [AF_INET6
only] Initializes IPv6-related data structures and assigns an
IPv6 link-local address to the interface. [AF_INET6
only] Removes any IPv6 configuration associated with the inter‐
face, including all IPv6 addresses and IPv6 routes through the
interface. This command is equivalent to the ifconfig interface
inet6 delete command. Sets the routing metric, or number of
hops, for the interface to the value of number. The default
value is 0 (zero) if number is not specified, indicating that
both hosts are on the same network. The routing metric is used
by the routed and gated daemons, with higher metrics indicating
that the route is less favorable. [AF_INET only] Enables the
use of multiple subnets on the interface. This is required when
an IP alias address is configured on an interface and it is in a
different subnet than the primary IP address of the interface.
[AF_INET only] Disables the use of multiple subnets on the
interface. [AF_INET only] Specifies how much of the address to
reserve for subdividing networks into sub-networks. This param‐
eter can only be used with an address family of inet. Do not
use this parameter if you are specifying the CIDR mask (/bit‐
mask) with the address argument, alias parameter, or aliaslist
parameter.
The mask variable includes both 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 hexadeci‐
mal number beginning with 0x, in the standard Internet dotted-
decimal notation, or beginning with a name.
The mask contains 1s (ones) for the bit positions in the 32-bit
address that are reserved for the network and subnet parts, and
0s (zeros) for the bit positions that specify the host. The
mask should contain at least the standard network portion.
The default netmask is based on the address parameter's network
class. Sets two NetRAIN interface timing parameters. The t1
parameter specifies the time period, in seconds, that the traf‐
fic monitor thread delays between reads of the interface coun‐
ters when the network is running normally. If there is no
change in the received byte count for t1 seconds, the traffic
monitor thread issues a yellow alert. The recommended t1 value
is 4.
The t2 parameter specifies the traffic-free time period, in sec‐
onds, that must pass before the traffic monitor thread declares
the interface dead. The recommended t2 value is 10 for Ethernet
interfaces and 16 for Asynchronous Transfer Mode (ATM) LAN Emu‐
lation (LANE) interfaces.
You can specify decimal values for both the t1 and t2 parameters
(for example, 1.5 or 0.8). If you do this, the values are vali‐
dated similarly to the nr_timeout_t and nr_timeout_o kernel
attributes. See sys_attrs_netrain(5) for more information on
minimum and maximum NetRAIN timer values.
NetRAIN uses Network Interface Failure Finder (NIFF) to monitor
the NetRAIN interfaces. See nifftmt(7) for more information.
Associates a virtual Media Access Control (MAC) address (mac-
address) with an IP network address. You must specify an alias
address with this command. The system sends an ARP “whohas”
request containing the physical address followed by an ARP “who‐
has” request containing the virtual MAC address.
This association is in effect only until the system is rebooted.
To establish this association automatically each time the system
is booted, edit the inet.local file and add the ifconfig
physaddr entries to it. Disassociates the virtual MAC address
(mac-address) from an IP network address. Sets the interface
into promiscuous mode. This directs the network interface to
receive all packets off the network, rather than just those
packets directed to the host. Disables the promiscuous mode of
the interface. This is the default. [AF_INET6 only] Marks the
address as proxy only. The system will only respond to Neighbor
Solicitations for this address and will drop other IPv6 packets.
Removes one or all interfaces attached to a NetRAIN interface.
If you do not specify an interface-id, all interfaces are
removed from the NetRAIN set, their default hardware addresses
are restored, and the UP option is cleared. The hardware
address of the NetRAIN virtual interface is set to
00:00:00:00:00:00 and its UP option is cleared.
If you specify only one interface-id and it is a member of the
NetRAIN interface (nrx), the interface is removed from the
NetRAIN set. If interface-id is also the active interface and
there are other interfaces in the set, the active interface is
switched to another interface in the set.
If there is only one interface in the NetRAIN set, the following
two commands are equivalent: ifconfig nrx remove ifconfig nrx
remove interface-id
You can also reconfigure the NetRAIN virtual interface by using
the add command. Sets the speed at which the token ring adapter
transmits and receives on the token ring network to value. The
value can be either 4 for a ring speed of 4Mbs or 16 for 16Mbs.
The adapter speed must match the signal speed of the token ring.
This parameter also determines the speed (regular, fast, or
gigabit Ethernet) and half- or full-duplex mode operation on the
interface when that interface is using the twisted-pair port as
follows:
Value Configuration
10 10 Mbps Ethernet half-duplex
20 10 Mbps Ethernet full-duplex
100 100 Mbps Ethernet half-duplex
200 100 Mbps Ethernet full-duplex
1000 1000 Mbps Ethernet half-duplex
2000 1000 Mbps Ethernet full-duplex
After the interface is online, you can use the ifconfig up and
down options to change the speed value dynamically. Stop
adapter transmission with down and set the speed in the same
command line. Then specify up without a speed value to restart
the adapter. Force a NetRAIN interface to failover to another
interface in the NetRAIN set. If the ifconfig interface-id
specified is the NetRAIN virtual interface, the next available
interface in the set becomes active. If the ifconfig interface-
id is a member of the NetRAIN set, the interface-id specified
becomes the active member. If the interface-id specified is not
operational, the switch command has no effect. Requests the use
of a trailer link-level encapsulation when sending messages.
If a network interface supports trailers, the system will, when
possible, encapsulate outgoing messages in a manner that mini‐
mizes the number of memory-memory copy operations performed by
the receiver. On networks that support the Address Resolution
Protocol (see arp), this option indicates that the system should
request that other 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. Disables the use of a trailer link-level encap‐
sulation. This is the default. Sets the trust group identifier
for the interface. Trust group identifiers are passed from the
kernel to the screend daemon, and indicate the color of the
interface on which a packet was received and the color of the
interface to which a packet is intended, as indicated by the
kernel routing tables. The group can be one of the primary col‐
ors in the visible spectrum (for example, red, orange, yellow,
green, blue, indigo, and violet). The screend daemon can
optionally use trust group information to make packet screening
decisions.
By default, the trust group identifier is unknown, meaning any
interface. Only application gateways for firewall services use
trust group identifiers. Marks an interface as working (up).
This parameter is used automatically when setting the first
address for an interface, or can be used to enable an interface
after an ifconfig down command. If the interface was reset when
previously marked with the parameter down (see the following
section for a description of this parameter), the hardware will
be reinitialized. Associates a virtual Media Access Control
(MAC) address (mac-address) with an IP network address. You
must specify an alias address with this command. The system
sends both initial ARP “whohas” requests containing the virtual
MAC address.
This association is in effect only until the system is rebooted.
To establish this association automatically each time the system
is booted, edit the inet.local file and add the ifconfig
vphysaddr entries to it.
Use the -physaddr mac-address option to remove the virtual MAC
address association.
Display options
When you issue the ifconfig command for an interface you might see any
of the following options: The interface will receive all multicast
packets. The interface supports broadcast packets. This is a read-
only option that is set by the driver. Driver-dependent debugging is
enabled. The interface is a loopback mode. Packets transmitted on
this interface will be looped back in the driver and not be transmitted
out on the network. The interface supports multicast packets. This is
a read-only option that is set by the driver, does not mean that a mul‐
ticast address is configured for the interface. Multiple networks are
configured on the interface. This means that an IP alias is in a dif‐
ferent subnet than the primary IP address. The interface is not using
address resolution protocol (ARP). It will neither transmit nor
respond to ARP requests. The interface does not perform checksums on
transmitted or received packets. Use this only on very reliable net‐
work media. Trailer link-level encapsulation for transmitted packets
is disabled. The interface is actively transmitting packets. This is
a read-only option that is set by the driver. All packets transmitted
on this interface are copied and passed to the packet filter program.
The interface is point-to-point link. This is a read-only option that
is set by the driver. The interface is in promiscuous mode. All pack‐
ets received are copied and passed to the packet filter program. UP
interface marked DOWN due to cluster quorum loss. The interface is
reserved for use by another virtual interface. Members of a NetRAIN set
are reserved by the NetRAIN virtual interface; members of a link aggre‐
gation group are reserved by the LAG virtual interface; and interfaces
that are enabled for VLAN are reserved by the VLAN virtual interface.
Reserved interfaces are not available for general purpose use by
the system. Therefore, the following typical operations are not
available to them: The interface's flags (for example, up or
down, and promiscuous mode) cannot be changed. The interface
cannot be configured with IPv4 or IPv6 addresses. The inter‐
face's characteristics (for example, mtu and speed) cannot be
changed. The interface's physical address cannot be changed,
and VMAC addresses cannot be configured.
If you attempt to perform any of these operations on a reserved
interface, the operation will fail and a Function not imple‐
mented error message will be displayed.
In general, you must perform these operations on the reserving
virtual interface (for example, nr0, lag1, and vlan222). How‐
ever, NetRAIN configuration commands may be issued even if the
NetRAIN virtual interface is itself reserved. The driver has
allocated resources for the interface, and is ready to transmit
and receive packets. This is a read-only option that is set by
the driver. It is not applicable to loopback devices, for exam‐
ple, lo0. The interface cannot hear its own transmissions.
This is a read-only option that is set by the driver. The
interface is currently in IEEE 802.1q tagging support mode. The
interface is up. This option is turned on when an address has
been configured on the interface. The interface supports vari‐
able Maximum Transmission Unit (MTU) sizes. The is a read-only
option that is set by the driver.
In addition, you might see NetRAIN, VLAN, and link aggregation virtual
interface relationships, if any.
EXAMPLES
To query the status of serial line interface sl0, enter: $ ifconfig sl0
sl0: options=10<POINTOPOINT> To configure the local loopback interface,
enter: # ifconfig lo0 inet 127.0.0.1 up
Only a user with superuser authority can modify the configura‐
tion of a network interface. To configure a ee0 interface,
enter: # ifconfig ee0 212.232.32.1/22
The broadcast address is 212.232.35.255 as the 22-bit mask spec‐
ifies four Class C networks. To configure the token ring inter‐
face for a 4 Mbps token ring with a netmask of 255.255.255.0 in
CIDR format, enter: # ifconfig tra0 130.180.4.1/24 speed 4 To
stop the token ring interface and start it for a 16 Mbps token
ring, enter: # ifconfig tra0 down # ifconfig tra0 speed 16 up To
configure IPv6 on a ee0 interface, enter: # ifconfig ee0 ipv6 up
To create a NetRAIN set nr1 with the Ethernet interfaces ee0 and
ee2 as the set members, enter: # ifconfig nr1 add ee0,ee2
To set the IP address of this interface to 18.240.32.40, enter:
# ifconfig nr1 inet 18.240.32.40
To view this set, enter: # ifconfig nr1 nr1:
options=c63<UP,BROADCAST,NOTRAILERS,RUNNING,MULTICAST,SIMPLEX>
NetRAIN Attached Interfaces: ( ee0 ee2 ) Active Interface: ( ee0
) inet 18.240.32.40 netmask ffffff00 broadcast 18.240.32.255
ipmtu 1500
To add interfaces ee1 and ee3 to this set, enter: # ifconfig nr1
add ee1 # ifconfig nr1 add ee3
To remove the interface ee0 from the NetRAIN set created in the
previous example, enter: # ifconfig nr1 remove ee0
To disassemble the entire NetRAIN set created in the previous
example, enter: # ifconfig nr1 remove To add alias 132.50.40.35
with a netmask of 255.255.255.0 in CIDR format to interface tu0,
enter: # ifconfig tu0 alias 132.50.40.35/24 To add network
addresses 40 through 50, inclusive, to subnets 18.240.32,
18.240.33, 18.240.34, 18.240.35, and 18.240.36 with a netmask of
255.255.255.0 in CIDR format to the tu0 interface, enter: #
ifconfig tu0 aliaslist 132.240.32-36.40-50/24 To add network
addresses 40 through 50, inclusive, to subnets 18.240.32,
18.240.64, and 18.240.96 with a netmask of 255.255.255.0 in CIDR
format to the tu0 interface, enter: # ifconfig tu0 aliaslist
132.240.32,64,96.40-50/24 To stop Ethernet interface tu0, delete
all addresses associated with the interface, and close all TCP
connections, enter: # ifconfig tu0 down delete abort
145.92.16.1: aborting 7 tcp connection(s) To delete the alias
address 145.92.16.2 on interface tu0 and close all TCP connec‐
tions, enter: # ifconfig tu0 -alias 145.92.16.2 abort
145.92.16.2: aborting 2 tcp connection(s) To create an IPv6
address for prefix AB:CD:CE:AB, enter: # ifconfig tu0 inet6
ip6prefix AB:CD:CE:AB::/64
To associate MAC address aa:01:81:43:02:11 with the alias
address 145.92.16.2, enter: # ifconfig tu0 alias 145.92.16.2
physaddr aa:01:81:43:02:11 To disassociate MAC address
aa:01:81:43:02:11 from the alias address 145.92.16.2, enter: #
ifconfig tu0 -alias 145.92.16.2 -physaddr aa:01:81:43:02:11 To
display the names of the interfaces on the system only, enter: #
ifconfig-l fta0 lo0 tu0 tu1 To display the hardware and IP
address of interface tu0, enter: # ifconfig-v tu0 tu0:
options=c63<UP,BROADCAST,NOTRAILERS,RUNNING,MULTICAST,SIMPLEX>
HWaddr 8:0:2b:9e:14:a2 inet 192.140.34.16 netmask ffffff00
broadcast 192.140.34.255 ipmtu 1500
ERRORS
Broadcast can only be used with address, alias or aliaslist parameters.
Explanation
The broadcast option was specified without an address parameter.
Cannot set primary and alias addresses, or multiple alias addresses.
Explanation
You specified more than one alias alias_address parameter on the
same ifconfig command line or you specified an alias and an
interface-id on the same command line.
Invalid bitmask
Explanation
The bitmask specified is not in the range of 1 to 32, inclusive.
Netmask cannot be used with bitmask.
Explanation
The netmask option was specified together with a CIDR bitmask.
Netmask can only be used with address, alias or aliaslist parameters.
Explanation
The netmask option was specified without an address parameter.
No such device: nrx
Explanation
You specified the switch option and no other physical interfaces
that are part of the NetRAIN set are UP; it is impossible to
switch interfaces.
FILES
Specifies the command path Interface access filtering configuration
file File to invoke local network commands
RELATED INFORMATION
Commands: lan_config(8), netstat(1), niffconfig(8), pfconfig(8),
sysconfig(8)gated(8), routed(8), screend(8)
Files: ifaccess.conf(4), inet.local(4)
Interfaces: nifftmt(7), nr(7)
System Attributes: sys_attrs_netrain(5)
Network Administration: Connections
ifconfig(8)