Determining IP Address

This page offers suggestions on how one might determine the IP address associated with a particular system.

Internet IP Address

There are many ways in which one can determine the Internet IP address associated with a particular system.

For Client Side Scripting

The following URLs will return your IP address (as you appear to the Internet) as a simple text string:

• http://nst.sourceforge.net/nst/cgi-bin/ip.cgi
• http://www.networksecuritytoolkit.org/nst/cgi-bin/ip.cgi
• http://whatismyip.org/

The following bash script fragment demonstrates how one can retrieve the Internet IP address and store it in a variable:

# Use wget to retrieve the IP address
IP_ADDRESS="$(wget -O - http://nst.sourceforge.net/nst/cgi-bin/ip.cgi 2>/dev/null)";

The getipaddress script uses this basic technique and adds error checking, caching and the ability to use multiple sources (should a server be down). The following demonstrates how one would achieve similar results using the --public-address option provided by the getipaddr script:

# Use getipaddress to retrieve the IP address
IP_ADDRESS="$(getipaddr --public-address)";