optimize apache example.com => www.example.com

[missjojo]

use

RewriteCond %{HTTP_HOST} !^www\. [NC]
RewriteCond %{SERVER_ADDR} !=127.0.0.1

replace

RewriteCond %{HTTP_HOST} !^www\..+$ [NC]
RewriteCond %{HTTP_HOST} !=localhost [NC]
RewriteCond %{HTTP_HOST} !=127.0.0.1

because:

1. save bits;
2. cover some non localhost virtual host such as a DIY xx.dev instead of localhost using hosts.

anyone agree?

[alrra]

Thanks @a25ce1!

Change made in fb1699d, but left localhost in (see: h5bp/server-configs#152).

[missjojo]

Thank you. But my other suggest is change RewriteCond %{HTTP_HOST} !=127.0.0.1 to RewriteCond %{SERVER_ADDR} !=127.0.0.1. Not just remove RewriteCond %{HTTP_HOST} !=localhost [NC].

This is good for automatic adjust to all virtual name for local environment, not just only for 127.0.0.1 and localhost, but also for other-local-virtual-names. 😄

[alrra]

RewriteCond %{SERVER_ADDR} !=127.0.0.1

@a25ce1: Sorry I've kinda missed that, mainly because the first time I've tested it didn't work on my machine (the reason was localhost was mapped to ::1, so %{SERVER_ADDR} ended up being ::1 instead of 127.0.0.1).

Thanks for bring it up again!

From http://en.wikipedia.org/wiki/Localhost:

The resolution of the name 'localhost' to the most-commonly used loopback addresses is set up by the following lines in each device's hosts file:

127.0.0.1 localhost
::1 localhost

So, I think a better solution would be:

<IfModule mod_rewrite.c>
    RewriteCond %{HTTPS} !=on
    RewriteCond %{HTTP_HOST} !^www\. [NC]
    RewriteCond %{SERVER_ADDR} !=127.0.0.1
    RewriteCond %{SERVER_ADDR} !=::1
    RewriteRule ^ http://www.%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
</IfModule>              

[missjojo]

That's right. I get new knowledge from you. You are very kind. Thanks! 😉

[jaimergp]

I know this is is old, but... who would want a non-www to www redirect when accessing via server IP? I know it's a corner case, but I think there's no harm in adding another condition like:

RewriteCond %{HTTP_HOST} !([0-9]{1,3}\.){3}[0-9]{1,3}

Correct me if I'm wrong please!

[mathiasbynens]

@jaimergp I expect everyone to be redirected to the one, true, canonical version of the URL they accessed. You wouldn’t want the site at the server IP to be indexed separately by search engines, would you?