301将旧网址重定向到新网址-Codeigniter

Question

I hope to get some help here. We had a static php website for a few years and recently we redesigned the site in codeigniter. Now after redesign many of our urls have changed, eg

example.com/about_us became example.com/about
example.com/programs-list became example.com/programs
and so on.

Our old urls were throwing up a 404 error. We asked the developer to add a 301 redirect for the old urls so that our SEO juice is fully passed on by google to the new urls. The developer says he has given a redirect using the routes.php file (and it is working) but I am not sure if it is really a 301 redirect. In most cases I have seen, a 301 redirect is added using the htaccess file. What is happening is that now when we go to the link example.com/about_us (which was the old url) it does display the contents of the new page (example.com/about) but the url in the address bar still stays example.com/about_us. My understanding is that if we add a 301 redirect it should simply redirect the link from example.com/about_us to example.com/about in the address bar. At the moment both of pages example.com/about and example.com/about_us are loading. Is this the correct way or are we missing something.

Appreciate your guidance.

Thank you

Here is my htaccess:

<IfModule mod_rewrite.c>
RewriteEngine On
# !IMPORTANT! Set your RewriteBase here and don't forget trailing and leading
#  slashes.
# If your page resides at
#  http://www.example.com/mypage/test1
# then use
# RewriteBase /mypage/test1/
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php?/$1 [L]
</IfModule>
<IfModule !mod_rewrite.c>
# If we don't have mod_rewrite installed, all 404's
# can be sent to index.php, and everything works as normal.
# Submitted by: ElliotHaughin
ErrorDocument 404 /index.php
RewriteRule ^(about_us)\.php$ /about/$1 [R=301,NC,L,QSA]
</IfModule>

Answer 1

.htaccess redirect

for same url use following code

      Redirect 301 /oldfile.htm /newfile.htm

Add this code or create new .htaccess file in the old-page.html directory. Single URL redirect Permanent redirect from old-page.html to new-page.html. .htaccess:

       Redirect 301 /old-page.html http://www.example.com/new-page.html

Entire domain redirect

Permanent redirect from all domain pages to newdomain.com. .htaccess file should be at the old website's root directory. .htaccess:

             Redirect 301 / http://www.newexample.com/