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3.4 When using a function like GetLocalAddress to programmatically check web site’s IP or look into IIS 7.0 log, the result is “::1” instead of “127.0.0.1” or a string like "fe80::e1ac:c656:a6bd:d619
%10". Why? [top]
The result is expected. These are IPv6 addresses instead of IPv4. ::1 is the local loopback address of IPv6 which is corresponding to 127.0.0.1 in IPv4 format.
By default, IPv6 is enabled on Windows 2008. If you want to disable it, go to Control Panel->Network and Sharing Center->Manage network connections. Uncheck IPv6 in your network connection's property. However, this will not disable the loopback interface of IPv6 which means http://localhost/ will still result in ::1. To fully disable all IPv6 interfaces on the server, we need to create and set DisabledComponents registry property to 0xffffffff under:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip6\Parameters .
and reboot the server. IE and IIS7 will start to use IPv4 addresses after this.
Reference:
929852 How to disable certain Internet Protocol version 6 (IPv6) components in Windows Vista
http://support.microsoft.com/default.aspx?scid=kb;EN-US;929852