Now before getting into the details of how to configure Red Hat Linux for root logins, keep in mind that this is VERY BAD security. Make sure that you NEVER configure your production servers for this type of login.

Configure Telnet for root logins

Simply edit the file /etc/securetty and add the following to the end of the file:

pts/0
pts/1
pts/2
pts/3
pts/4
pts/5
pts/6
pts/7
pts/8
pts/9

This will allow up to 10 telnet sessions to the server as root.

Configure FTP for root logins

Edit the files /etc/vsftpd.ftpusers and /etc/vsftpd.user_list and remove the 'root' line from each file.


source: Configuring Telnet/FTP to login as root (Linux)