Rackspace Cloud Essentials - Install vsftpd for CentOS

Previous section: Create a Cloud Server

By following the previous articles in this series, you should now have an active cloud server that is secured and has scheduled backups configured. Next, you'll want to upload your web content to the server. When you think of transferring files, you probably think of the File Transfer Protocol (FTP) because it has been around for so long. Although simple to use, FTP has become obsolete because it lacks the ability for secure file transfers.

Instead, we recommend installing and using a secure file transfer mechanism. This article describes how to install vsftpd (very secure FTP daemon) and the FTP client, and also walks you through some useful administration and security steps.

Install and run vsftpd

Use the group installation that is available in the YUM package manager.

  1. Run the following command to install everything you need:

    sudo yum install vsftpd

  2. To start vsftpd, run the following command:

    sudo service vsftpd start

Configure vsftpd

Now that you have a working installation of vsftpd on the server, you can make a few of configuration changes for security and convenience. These change might include:

  • starting vsftp on reboot
  • configuring the firewall

Set the vsftp service to start on reboot

You can use the chkconfig tool to view which services start automatically when the server starts, and on which run level they start. To get vsftpd to start on the most common run levels (3,4,5), run the following command:

sudo chkconfig vsftpd on

Verify the "on" status by checking the chkconfig output for vsftpd:

chkconfig --list vsftpd

The standard vsftpd configuration file and all subsequent files for CentOS reside in the /etc/vsftpd/ directory. The most important file in this directory is vsftpd.conf. You need to make two changes to this file for security and convenience: disable anonymous users and restrict user access. These are the changes described in the next two sections.

To get started, open the /etc/vsftpd/vsftpd.conf file in your favorite text
editor.

Disable anonymous users

We recommend disabling anonymous FTP, unless you have a specific requirement to
use it.

Change the value for anonymous_eanble to No, as follows:

# Allow anonymous FTP? (Beware - allowed by default if you comment this out).
anonymous_enable=NO
Restrict user access

Now configure vsftpd to be able to chroot (commonly referred to as jailing) users to their home directories for security and privacy.

  1. Change the value of chroot_list_enable to No, as follows:

    # You may specify an explicit list of local users to chroot() to their home
    # directory. If chroot_local_user is YES, then this list becomes a list of
    # users to NOT chroot().
    chroot_list_enable=NO
    # (default follows)
    chroot_list_file=/etc/vsftpd/chroot_list
    
  2. Ensure that users are jailed in their home directory by adding the following
    entry to the bottom of the file:

        chroot_local_user=YES
    
  3. Save the /etc/vsftpd/vsftpd.conf file.

  4. So that you do not get an error when restarting, create the chroot_list
    file, as follows:

        sudo touch /etc/vsftpd/chroot_list
    

Configure the firewall

  1. Open ports in your firewall by running the following command:

    sudo iptables -I INPUT 4 -m tcp -p tcp -m conntrack --ctstate NEW --dport 21 -j ACCEPT
    
  2. Save your configuration:

    sudo service iptables save
    
  3. Open the /etc/sysconfig/iptables-config file in your favorite editor.

  4. Verify that the IPTABLES_MODULES variable is specified as ip_conntrack_ftp
    (CentOS 5) or nf_conntrack_ftp (CentOS 6), as shown in the following examples:

     -  Centos 5 (ip_conntrack_ftp):
    
               IPTABLES_MODULES="ip_conntrack_ftp"
    
     -  Centos 6 (nf_conntrack_ftp):
    
                IPTABLES_MODULES="nf_conntrack_ftp"
    
  5. Save the iptables-config file and restart iptables:

    sudo service iptables restart
    

Access your server through FTP

Use one of the following methods to access the server.

Using a browser

Enter the name of your FTP site into a browser address bar, as shown in the
following screenshot, and supply the login credentials when prompted.

Using an FTP client

Use one of the many low-cost or free FTP applications, which are available for
download.

Using the command line

Use the following syntax to open an FTP session from the command line, where
example.com is your FTP site:

ftp example.com

To close the FTP session, type exit in the session window.

Next section: Rackspace Cloud Essentials - Configure a user in vsftpd