Can I use .htaccess file to block traffic from specific IP addresses?

Answer by: Andrew Hickl, Aplus.Net Knowledge Base Support.

.htaccess files can be used to block traffic from specific IP addresses that may be trying accessing your site maliciously.

Here’s how to do it:

1. Start by editing the .htaccess file in the directory you’re looking to customize.  (We recommend editing it using the “Edit” function found in the File Manager on the Control Panel.)  If you currently do not have a .htaccess file, create one locally using a text editor like NotePad (Windows), SimpleText (Macintosh) or Emacs (Linux / UNIX).

2. Next, enter the following code into your .htaccess file:

You will need to replace ‘domain.com’ in the code above with either the IP address or the domain name of the site(s) that you want to grant or deny access to your site. If you’re granting / denying access to several individual sites, you’ll need to make each request on an individual line, as in the following example:

In order to grant / deny access to all users, simply replace ‘domain.com’ in the above examples with the word ‘all’.  For example:

In the example above, traffic from originating at http://apluskb.com is blocked, but all other traffic is permitted.

3. Save your .htaccess file to your local computer.
   
   
4. Open your FTP client and establish a connection to your web space using your FTP Username and FTP Password.  Your connection URL should be www.yourdomainname.com (where ‘yourdomainname.com’ = the actual name of your domain).

5. Browse to the directory that you’d like to customize.
   
   
6. Set your upload settings to ASCII.  (Uploading .htaccess files in ‘binary’ format may have unexpected consequences.)
   
   
7. Upload your .htaccess file from your local computer.
   
   
8. After the upload is completed, you may need to change the file permissions for the .htaccess file.  They should be set to 644 (using chmod) or RW-R--R--.

Note: If you have a Windows-based hosting plan, you cannot use .htaccess files.