Aliasing, Redirecting and Rewriting in Apache

Difference between Aliasing, Redirecting and Rewriting in Apache

Aliasing refers to mapping a URL to a particular directory

Redirecting refers mapping a URL to another URL

Rewriting refers to using mod_rewrite module to alter an URL

Aliasing

Alias directive helps with aliasing as follows

1) To map URLs to a directory outside of the DocumentRoot directory tree

Eg:

To view the directory contents of user xyz through an URL, add the following entries in httpd.conf file


Alias /xyz /home/xyz

<Directory "/home/xyz">
    Options Indexes MultiViews FollowSymLinks
    AllowOverride None
    Order allow,deny
    Allow from all
</Directory>

Access the directory contents of user xyz as follows now
                 http://localhost/xyz

2) Helps in accessing the same content using different names

Eg: 

For the example shown above, suppose I want to access the contents of user "xyz" with name "abc" in httpd.conf file as follows

Alias /abc  /home/xyz

Now both the URLs show the same content

  http://localhost/xyz
  http://localhost/abc

Redirecting

Redirect maps a URL to another URL. The second argument to Redirect directive is a full URL.

Eg:

I want all requests coming to URL, http://localhost/xyz to be redirected to http://anonexp.blogspot.com

        http://localhost/xyz    ---->  http://anonexp.blogspot.com

In httpd.conf file, make the following entry

       Redirect   "/xyz"        "http://anonexp.blogspot.com"

From access_log file, we can confirm the redirection from 302 status

192.168.1.4 - - [03/Mar/2013:07:53:16 +0530] "GET /xyz/ HTTP/1.1" 302 290 "-" "Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20100101 Firefox/12.0"