IPCONFIG
Last updated: 1/16/04

Q. How do I check my network IP address in Windows XP (and in Windows 2000/NT)?

A. Open a DOS windows in Windows XP (Start, All Programs, Accessories, Command Prompt). Enter at the command prompt enter ipconfig, e.g...

C:\Documents and Settings\Larry F. Byard>ipconfig

Windows IP Configuration

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 192.168.123.197
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.123.254

To obtain the syntax for ipconfig, enter ipconfig /?.

C:\Documents and Settings\Larry F. Byard>ipconfig /?

USAGE:
ipconfig [/? | /all | /renew [adapter] | /release [adapter] |
/flushdns | /displaydns | /registerdns |
/showclassid adapter |
/setclassid adapter [classid] ]

where
adapter Connection name
(wildcard characters * and ? allowed, see examples)

Options:
/? Display this help message
/all Display full configuration information.
/release Release the IP address for the specified adapter.
/renew Renew the IP address for the specified adapter.
/flushdns Purges the DNS Resolver cache.
/registerdns Refreshes all DHCP leases and re-registers DNS names
/displaydns Display the contents of the DNS Resolver Cache.
/showclassid Displays all the dhcp class IDs allowed for adapter.
/setclassid Modifies the dhcp class id.

The default is to display only the IP address, subnet mask and
default gateway for each adapter bound to TCP/IP.

For Release and Renew, if no adapter name is specified, then the IP address
leases for all adapters bound to TCP/IP will be released or renewed.

For Setclassid, if no ClassId is specified, then the ClassId is removed.

Examples:
> ipconfig ... Show information.
> ipconfig /all ... Show detailed information
> ipconfig /renew ... renew all adapters
> ipconfig /renew EL* ... renew any connection that has its

name starting with EL
> ipconfig /release *Con* ... release all matching connections, eg. "Local Area Connection 1" or
"Local Area Connection 2"

If your PC is connected to the a device such as broadband router or cable MODEM with a DHCP server, you are using automatic IP addresses, and you want to test it, config /release and ipconfig /renew to release and renew the IP address lease. You should see it change, however, the new IP address may be the same as the old one. Larry