IPCONFIG(8)

NAME
ipconfig - view and control IP configuration state

SYNOPSIS
ipconfig waitall
ipconfig getifaddr interface-name
ipconfig ifcount
ipconfig getoption interface-name (option-name | option-code)
ipconfig getpacket interface-name
ipconfig set interface-name NONE
ipconfig set interface-name (DHCP | BOOTP)
ipconfig set interface-name (MANUAL | INFORM) ip-address subnet-mask
ipconfig setverbose level

DESCRIPTION
ipconfig is a utility that communicates with the IPConfiguration agent to retrieve and set IP configuration parameters. It should only be used in a test and debug context. Using it for any other purpose is strongly discouraged. Public API's in the SystemConfiguration framework are currently the only supported way to access and control the state of IPConfiguration.

The IPConfiguration agent is responsible for configuring and managing the IP addresses on direct, connectionless interfaces such as IEEE 802.3 Ethernet and IEEE 1394 FireWire. The IPConfiguration agent is a program bundle that is loaded and executed by the configd(8) process.

The IPConfiguration agent implements the client side of the DHCP and BOOTP protocols described in RFC951, RFC1542, RFC2131, and RFC2132. It also assigns and maintains static IP addresses. It may also allocate and assign a link-local IP address if DHCP fails to acquire an IP address.

In all cases, the IPConfiguration agent performs IP address conflict detection before assigning an IP address to an interface.

COMMANDS
The ipconfig utility provides several commands:

waitall
    Blocks until all network services have completed configuring, or have timed out in the process of configuring. This is only useful for initial system start-up time synchronization for legacy network services that are incapable of dealing with dynamic network configuration changes.

getifaddr interface-name
    Prints to standard output the IP address for the first network service associated with the given interface. The output will be empty if no service is currently configured or active on the interface.

ifcount
    Prints the number of interfaces that IPConfiguration is capable of configuring. The value that's printed will not change unless relevant network interfaces are either added to or removed from the system.

getoption interface-name (option-name | option-code)
    Prints the BOOTP/DHCP option with the given name or option code integer value. See bootpd(8) for option code names. If an option has multiple values e.g. domain_name_server, only the first value is printed.

getpacket interface-name
    Prints to standard output the DHCP/BOOTP packet that the client accepted from the DHCP/BOOTP server. This command is useful to check what the server provided, and whether the values are sensible. This command outputs nothing if DHCP/BOOTP is not active on the interface, or the attempt to acquire an IP address was unsuccessful.

set interface-name NONE
set interface-name (DHCP | BOOTP)
set interface-name (MANUAL | INFORM) ip-address subnet-mask
    Sets the interface to have a new temporary network service of the given type. All existing services on the interface are first de-configured before the new service is instantiated. If NONE is supplied, no new service is instantiated.

    DHCP and BOOTP require no additional arguments. The IP address, subnet mask, router, and DNS information are retrieved automatically.

    Both MANUAL and INFORM require the specification of an IP address ip-address and a subnet mask subnet-mask.

    The INFORM service configures the IP address statically like MANUAL, but then broadcasts DHCP INFORM packets to retrieve DHCP option information. If the DHCP server responds and supplies a subnet mask, that subnet mask is used instead of the specified subnet-mask.

    The set command requires root privileges.

    Note: The set command is very useful for debugging, but it can't be used to configure a persistent service. The temporary services that are created only remain until the next network configuration change occurs. See scselect(8).

setverbose level
    Sets verbose mode logging in the IPConfiguration agent. Specify a level value of 0 to disable verbose logging, the default. Specify a value of 1 to enable verbose logging.

    When enabled, useful debugging information is logged using syslog(3) with level LOG_NOTICE. In addition, the packet trace file /var/log/com.apple.IPConfiguration.bootp is opened and BOOTP/DHCP packets that are sent and received are printed to the file.

    The setverbose command requires root privileges.

EXAMPLES
# ipconfig getpacket en0
op = BOOTREPLY
htype = 1
dp_flags = 0
hlen = 6
hops = 0
xid = 1956115059
secs = 0
ciaddr = 0.0.0.0
yiaddr = 192.168.4.10
siaddr = 192.168.4.1
giaddr = 0.0.0.0
chaddr = 0:3:93:7a:d7:5c
sname = dhcp.mycompany.net
file =
options:
Options count is 10
dhcp_message_type (uint8): ACK 0x5
server_identifier (ip): 192.168.4.1
lease_time (uint32): 0x164a
subnet_mask (ip): 255.255.255.0
router (ip_mult): {192.168.4.1}
domain_name_server (ip_mult): {192.168.4.1}
domain_name (string): mycompany.net
end (none):

# ipconfig getoption en0 router
192.168.4.1

SEE ALSO

configd(8), bootpd(8), scselect(8)

HISTORY

The ipconfig command first appeared in Mac OS X Version 10.0 Public Beta.