Tuesday, May 15, 2007

Telnet and FTP Services on Red Hat Enterprise Linux

Linux is configured to run the Telnet and FTP server, but by default, these services are not enabled. To enable the telnet service, login to the server as the root user account and run the following commands:

# chkconfig telnet on
# service xinetd reload
Reloading configuration: [ OK ]

Starting with the Red Hat Enterprise Linux 3.0 release (and in CentOS Enterprise Linux), the FTP server (wu-ftpd) is no longer available with xinetd. It has been replaced with vsftp and can be started from /etc/init.d/vsftpd as in the following:

# /etc/init.d/vsftpd start
Starting vsftpd for vsftpd: [ OK ]

If you want the vsftpd service to start and stop when recycling (rebooting) the machine, you can create the following symbolic links:

# ln -s /etc/init.d/vsftpd /etc/rc3.d/S56vsftpd
# ln -s /etc/init.d/vsftpd /etc/rc4.d/S56vsftpd
# ln -s /etc/init.d/vsftpd /etc/rc5.d/S56vsftpd


Allowing Root Logins to Telnet and FTP Services

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

This will allow up to 4 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.
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