I attempt to install cPanel/WHM on CentOS 7 but was greet with an invalid hostname error. I never encounter this error before although I do many times cPanel/WHM installation.
Below is the error message.
Your hostname is invalid. Update the hostname to a fully qualified domain name and rerun the installer.
My first attempt to solve this is by changing hostname in network configuration file. Seem strange but the hostname configuration already correct.
Second attempt is by issuing the following command
hostname host.domain.net
I try to reinstall cPanel/WHM & it works!. Make sure you change host.domain.net to your preferred FQDN.
In dealing WordPress Login (wp-login.php) brute force attack, previously, I recommend changing username & password as mentioned in WordPress Brute Force Attack – Change Username/Login ID post.
It does help to prevent the hacker to gain access, but the attack caused another problem as it consumed a large amount of server resources. Plugins such as Brute Force Login Protection may assist you to block the IPs after a number of wrong attempts. However, some of the hackers have large numbers of IPs, from hundreds to thousands of IPs. I encounter this problem & really taxing my server resources similar to DDOS attack.
While looking for better alternative to solve this problem, I found out that if you are using Cloudflare, the request headers contain the country code of the visitor’s origin. The header I’m talking about is the “HTTP_CF_IPCOUNTRY”.
What you to do is to allow only visitors from certain country to access “wp-login.php” file by using “HTTP_CF_IPCOUNTRY” header and “.htaccess” file.
The example below is only allow visitors from United States & Canada. Change the country code in the third line to make it applicable to your locations.
<FilesMatch "wp-login.php">
RewriteEngine on
RewriteCond %{HTTP:CF-IPCOUNTRY} !^(US|CA)$
RewriteRule ^ - [F,L]
</FilesMatch>
