[EMAIL PROTECTED] wrote:
I'm trying to understand what loopback interface is used for and /how/ it is works.
I'm not exactly sure how it works. But it looks like a network interface, except it never leaves the box. This means that a Linux(UNIX) box with no network interfaces (no ethernet, no phone line, no ISDN, no toekn ring,no nothing) can still do all those neat networking protocol stuff.
Anyone got any examples of how an app uses loopback interface effectively??
Start a webserver. http://127.0.0.1/
Start an ftp server, ncftp 127.0.0.1
Start an X server DISPLAY=127.0.0.1:0; export DISPLAY (or setenv DISPLAY 127.0.0.1:0 for you *csh'rs)
I vaguely know it acts like a remote node without actually being one. I'd like the details.
Not sure what details you need.
-john
Quoted from:
http://www.geekcomix.com/cgi-bin/classnotes/wiki.pl?UNIX01/The_Loopback_Interface
Despite it coming from geekcomix the info is for real. It appeared in a series of tutorials called Unix01 written by Sam Hart who was/is affiliated with the Physics Department at the University of Arizona.
/begin quote The Loopback Interface
The loopback interface is a special kind of interface that allows applications and servers on your Linux machine to make connections back to the Linux machine. There are a variety of reasons why you would want to do something like this; you could be testing something out and not wish to disturb anyone on your local network, you could be running a server locally which will not have an external interface, or you could have specific encrypted tunneling you wish to do with an application that cannot natively support it. For the vast majority of Linux networking applications to work, you must have a loopback device.
Traditionally, the loopback interface is defined with the IP address of 127.0.0.1, thus, when you sit down at any Linux (or even UNIX) machine and connect to 127.0.0.1 you are connecting to the local machine. The loopback interface is also traditionally called 'lo'.
/end quote
Rick [EMAIL PROTECTED] -- [email protected] http://www.kernel-panic.org/cgi-bin/mailman/listinfo/kplug-list
