127.0.0.0 or 127.0.0.1?

127.0.0.0 or 127.0.0.1?

Post by Samuel Ziegl » Thu, 09 Jan 1997 04:00:00



Ok... I don't really have any problems with my machine when it comes to
networking.  However, I've noticed some strange behavior.  First off, what
should the inet address for the local loopback device be?  Mine is currently
at 127.0.0.0.  I remember reading somewhere that this was a Bad Thing.
However, I can telnet to 127.0.0.0 just fine.  Here is my ifconfig:
cerebus:~/$ ifconfig
lo        Link encap:Local Loopback  
          inet addr:127.0.0.0  Bcast:127.255.255.255  Mask:255.0.0.0
          UP BROADCAST LOOPBACK RUNNING  MTU:3584  Metric:1
          RX packets:89 errors:0 dropped:0 overruns:0
          TX packets:89 errors:0 dropped:0 overruns:0

However, localhost in my /etc/hosts is defined as 127.0.0.1.  As follows:
cerebus:~/$ cat /etc/hosts
127.0.0.1       localhost            
127.0.0.1       cerebus.bellatlantic.net cerebus

So I can also telnet to 127.0.0.1 as well.  And when I telnet to 127.0.0.1,
the number of packets transmitted and recieved changes for my loopback.  So
it appears that the loopback device is at 127.0.0.0 AND 127.0.0.1.  Is this
correct?  If not, what am I doing incorrectly?

--

 
 
 

127.0.0.0 or 127.0.0.1?

Post by Jon Martin Solaa » Thu, 09 Jan 1997 04:00:00



> Ok... I don't really have any problems with my machine when it comes to
> networking.  However, I've noticed some strange behavior.  First off, what
> should the inet address for the local loopback device be?  Mine is currently
> at 127.0.0.0.  I remember reading somewhere that this was a Bad Thing.
> However, I can telnet to 127.0.0.0 just fine.  Here is my ifconfig:
> cerebus:~/$ ifconfig
> lo        Link encap:Local Loopback  
>           inet addr:127.0.0.0  Bcast:127.255.255.255  Mask:255.0.0.0
>           UP BROADCAST LOOPBACK RUNNING  MTU:3584  Metric:1
>           RX packets:89 errors:0 dropped:0 overruns:0
>           TX packets:89 errors:0 dropped:0 overruns:0

> However, localhost in my /etc/hosts is defined as 127.0.0.1.  As follows:
> cerebus:~/$ cat /etc/hosts
> 127.0.0.1       localhost            
> 127.0.0.1       cerebus.bellatlantic.net cerebus

> So I can also telnet to 127.0.0.1 as well.  And when I telnet to 127.0.0.1,
> the number of packets transmitted and recieved changes for my loopback.  So
> it appears that the loopback device is at 127.0.0.0 AND 127.0.0.1.  Is this
> correct?  If not, what am I doing incorrectly?

Isn't 127, or 127.0.0.0 supposed to be the network address? The correct
address for the interface itself is 127.0.0.1

--
Jon Martin Solaas                              

http://www.ifi.uio.no/~jonso