.htaccess 301 redirect from old domain to new domain while structure of pages and url are same

Question

I want to redirect http://olddomain.com to http://newdomain.com for my all urls..keeping the page on new domain same. What i mean to say is URLs such as below

http://olddomain.com/home/category/page.html
http://olddomain.com/home/mybook/page2.html
http://olddomain.com/login

should be 301 redirect to the new newdomain but same pages, like below

http://newdomain.com/home/category/page.html
http://newdomain.com/home/mybook/page2.html
http://newdomain.com/login

this is what i have in my .htaccess currently

RewriteEngine on
RewriteCond $1 !^(index\.php|img|public|robots\.txt) [NC]
RewriteRule ^(.*)$ /index.php?/$1 [L]

Please help me to do this cleanly and exlpain things in details since i am new in this.

also does someone know how much time search engines might take to move away from the references of my olddomain? i mean the old-domain urls in search queries should be replaced by new-domain urls... n old domain should go away from search engines.

Answer 1

Add following code at the beginning of .htaccess -

    RewriteEngine On

    # Redirect Entire Site to New Domain
    RewriteCond %{HTTP_HOST} ^olddomain.com$ [OR]
    RewriteCond %{HTTP_HOST} ^another.olddomain.com$ [NC]
    RewriteRule ^(.*)$ http://newdomain.com/$1 [R=301,L]

Answer 2

Much simpler:

Redirect 301 / http://newdomain.com/

Replace your .htaccess file with that one line OR if you have access to it, put it in the apache conf file(s) for your old domain (I place it following the DocumentRoot directive).

See Redirecting and Remapping with mod_rewrite for more info.