127.0.0.1 vs 0.0.0.0


 
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Special Forums IP Networking 127.0.0.1 vs 0.0.0.0
# 1  
Old 08-17-2015
Network 127.0.0.1 vs 0.0.0.0

Which one should I use in '/etc/hosts'?
Please explain in details.

Random quotes on the topic:
Quote:
When you use the 0.0.0.0 method it doesnt try connect anywhere. But if you use 127.0.0.1 it actually tries to connect to a service on your computer which makes it take longer and use up more resources. Also you might run a webserver that it ask for invalid requests. Therefore it is better to use 0.0.0.0 than 127.0.0.1 as you want to kill the connection not to loop it back to your computer
Quote:
Why is it better? 0.0.0.0 doesn't connect anywhere. 127.0.0.1 does. If I run a web server that has a virtual host with the same domain name, it would serve the request.
Quote:
What does that have to do with 0.0.0.0? 0.0.0.0 has NO meaning on Linux, FreeBSD, or Mac OS-X and causes problems on those operating systems. The added benefit of using 127.0.0.1 is that the top phttpd (Pseudo HTTP Daemon) and Homer log what is being stopped and why.
Quote:
I have tested both ways in Windows XP and Windows Server 2003 only, and all I can tell so far is that using a template in this form:
127.0.0.1 google-analytics.com
127.0.0.1 ssl.google-analytics.com
is not good at all for my system, and it can slow down even the most common operations.

But I have found that using a template in this form:
0.0.0.0 google-analytics.com
0.0.0.0 ssl.google-analytics.com
seems to be ok as far as system stability is concerned, and even the webpages are loading faster.
# 2  
Old 08-17-2015
The culprit may be a "black hole" firewall response, which instead of refusing connection just stonewalls it by ignoring the attempt.
This User Gave Thanks to Corona688 For This Post:
# 3  
Old 08-18-2015
Unfortunately, 0.0.0.0 has different meanings depending on where it's used. The formal definition is given in RFC1122 Section 3.1.2.3, i.e this host on this network. Specifically, all available IP addresses on this host.

Assuming you are talking about a UNIX-like OS and not Microsoft Window, I have never seen 0.0.0.0 defined in /etc/hosts but have nearly always seen 127.0.0.1 defined. There simply is no reason to put 0.0.0.0 in /etc/hosts.
These 2 Users Gave Thanks to fpmurphy For This Post:
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