@robertjamespeacock

Using define() to set the constants should be all that’s required, unless the Apache configuration is using the IP as ServerName instead of your actual domain.

You can check the file in /etc/apache2/sites-available that corresponds to your website to see how the VirtualHost is setup. You’ll want to check ServerName and ServerAlias to see what is listed as the domain/IP.

Also make sure your domain is setup with the correct A entry pointing to your server IP.

Beyond that, clear your cookies/cache before trying to login again, just to make sure that isn’t the issue.

Thanks for the tips.

I did all that and I’ve managed to get it working. I think in the end it was something to with the write permissions for .htaccess.

Thanks to @robertjamespeacock, this is working on my wordpress webiste. But I still in confusion of is this work for security. How effective is this? I did blocking ip address using .htaccess file.