Obtaining IP Address and Other Information

This document is to assist you to quickly find your IP address as you may require this information from time to time to check you are connected to the LAN and have been issued a DHCP address.

The IP Address is the unique address given to each computer and must be configured correctly in order to function on the network over TCP/IP. It is good to learn what appropriate configurations are needed for your locations and reference it when problems arise. For example, you may have the correct IP but the gateway or DNS setting could be the problem.

What Is My IP Address?

Networking Applet Utility

Taskbar - Using the Network taskbar icon.

  1. Right mouse click on Network Icon available on task bar (Dialogue box will open)
  2. Click on the Connection Information option:
  3. Dialogue box "Connection Information" will popup containing the relevant information.
    - right mouse click on icon
    - left mouse click on Connection Information

Example Connection

Active Connection Information

Active Connection Information

The following is a summary of the connection information from the graphical tool. The key details are IP Address, which is the unique set of numbers assigned to your system, the default route which is the path your system takes to get to the Internet, and DNS information which takes hostnames like www.google.com and translates it for your computer which only undertands the IP number of that address.

Active Connection Chart

Ethernet Item Details Examples
  • the currently connected device
802.11 WiFi (wlan0), Wired Ethernet
Hardware Address
  • The unique MAC number for your card
  • Linux driver loaded for device
ath5k_pci, iwl4965
  • The connection max. capability
11Mb/s, 54Mb/s, 100Mb/s
  • Wireless encryption type
IP Address
  • The unique address for your machine,
Broadcast Address
  • The beacon address for your subnet,
Default Route
  • The path out of your subnet,
Primary DNS
  • Is how your system looks up names like google.com,
Secondary DNS
  • Is how your system looks up names like google.com,

Terminal Session Tools

Terminal Session Tools

Command prompt - This is a tad more complex and best left to experienced users.

  1. Open a shell prompt: Right Click on Desktop --> Click 'Open Terminal'. (or locate the terminal icon from the menu)
  2. Then switch to root with the su - command
    $ su -
    Password *******
  3. The ifconfig command is similar to Windows ipconfig, at the command prompt issue /sbin/ifconfig. (press the enter key after each command)
  4. this will return information on installed interfaces, look for inet addr: text as that is where the ip address is printed (see example below).
  5. If you know the device such as eth0 (Wired ethernet) or wlan0 (Wireless), you can show only that one device using ifconfig :
    #/sbin/ifconfig wlan0
    wlan0 Link encap:Ethernet HWaddr 00:05:4E:4C:75:45
    inet addr: Bcast: Mask:
    inet6 addr: fe80::205:4eff:fe4c:7545/64 Scope:Link
    RX packets:3652 errors:0 dropped:0 overruns:0 frame:0
    TX packets:4128 errors:0 dropped:0 overruns:0 carrier:0
    collisions:0 txqueuelen:1000
    RX bytes:2075441 (1.9 MiB) TX bytes:890207 (869.3 KiB)
  6. The route command prints the routing information:
    Kernel IP routing table
    Destination Gateway Genmask Flags Metric Ref Use Iface * U 0 0 0 wlan0
    default UG 0 0 0 wlan0
  7. The mii-tool will show if you have a hardware link from your system to a router/switch:
    eth0: negotiated 100baseTx-FD, link ok

    For example, in this example the Ethernet connection is 100 speed with FD meaning full duplex (the fastest type). If there was a problem with the wall drop or the router, the message "eth0: no link" would return to the screen.

  8. The service network restart command can be used to clean up a system much like rebooting:
    /sbin/service network restart

    This will restart devices set to start upon boot up (i.e. eth0), for Wireless, use the Network Applet to connect to a network.

  9. The ifup and dhclient commands will try to get an IP address:
    /sbin/dhclient eth0


    /sbin/ifdown eth0
    /sbin/ifup eth0
  10. The ping command checks if you can talk to the world:
    ping www.google.com


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