how to redirect a web page based on domain name using .htaccess

Question

At a site serving multiple domains (example.com, example.org, etc.), we would like to redirect a page depending on the domain:

https://www.example.com/page1 => https://www.example.com/page2
https://www.example.org/page1 => https://www.example.org/page3

using .htaccess, but the following:

Redirect "/page1" "https://www.example.com/page2"

will be applied to both domains. How can this be done?

Answer 1

The recommendation from the Apache project is:

In general, you should only use .htaccess files when you don't have access to the main server configuration file. [In other words: your site is on shared hosting and you don't have administrator level access to the main apache httpd configuration] ... a common misconception is that user authentication and mod_rewrite directives must go in .htaccess files.

Because there is a performance penalty for using the .htaccess mechanism.

So preferably you should simply adjust your httpd.conf (or the includes used to set up your sites) to have separate stanza's for each of your domains and make the necessary redirects there:

<VirtualHost *:443>
    DocumentRoot "/www/example"
    ServerName www.example.com

    # Other directives here

    Redirect "/page1" "https://www.example.com/page2"
</VirtualHost>

<VirtualHost *:443>
    DocumentRoot "/www/example"
    ServerName www.example.org

    # Other directives here

    Redirect "/page1" "https://www.example.org/page3"
</VirtualHost>

---

When you're on shared hosting and absolutely must use an .htaccess file; your question is actually off-topic for ServerFault, but the approach would be to make different conditional redirects, based on the HTTP Host: header the client uses.

You can alternatively accomplish this using the <If> directive:

<If "%{HTTP_HOST} == 'www.example.com'">
    Redirect "/page1" "https://www.example.com/page2"
</If>
<If "%{HTTP_HOST} == 'www.example.org'">
    Redirect "/page1" "https://www.example.org/page3"
</If>

Or with mod_rewrite rules :

RewriteCond "%{HTTP_HOST}"   "^www\.example\.com" [NC]
RewriteRule "^/page1"        "https://www.example.com/page2" [R]

RewriteCond "%{HTTP_HOST}"   "^www\.example\.org" [NC]
RewriteRule "^/page1"        "https://www.example.org/page3" [R]