:Build an FTP site on a CentOS 8 instance

Step 1: Install vsftpd

1. Connect to a Linux instance.

   For more information, see Connection methods.

2. Change the CentOS 8 repository address.

   CentOS 8 reached end of life (EOL). In accordance with Linux community rules, all content was removed from the following CentOS 8 repository address: http://mirror.centos.org/centos/8/. If you continue to use the default CentOS 8 repository on Alibaba Cloud, an error is reported. To use specific installation packages of CentOS 8, change the CentOS 8 repository address. For more information, see Change CentOS 8 repository addresses. .

3. Run the following command to install vsftpd:

   dnf install -y vsftpd

   If the following command output is returned, vsftpd is installed.

4. Run the following command to enable the FTP service to automatically start on system startup:

   systemctl enable vsftpd.service

5. Run the following command to start the FTP service:

   systemctl start vsftpd.service

   Note

   If the system returns the Job for vsftpd.service failed because the control process exited with error code error message when the preceding command is run, check whether the following issues occur and troubleshoot the issues.

   • If the network environment does not support IPv6 addresses, run the vim /etc/vsftpd/vsftpd.conf command to change the value of listen_ipv6 from YES to NO.

   • If the MAC address that is specified for a network interface controller (NIC) in the /etc/sysconfig/network-scripts/ifcfg-xxx configuration file is not the actual MAC address of the NIC, run the ifconfig command to query the MAC addresses of NICs. Then, add HWADDR=<Actual MAC address of the NIC> to the file or change HWADDR in the file to the actual MAC address of the NIC.

6. Run the following command to query the listening port of the FTP service:

   netstat -antup | grep ftp

   If the following command output is returned, the FTP service is started and listens on port 21.

   By default, the local user mode is enabled. To use the FTP service, configure other parameters.

Step 2: Configure vsftpd

In this example, vsftpd is configured in passive and local user modes to ensure data security.

1. Run the following command to create a Linux user for the FTP service.

   In this example, the ftptest user is created.

   adduser ftptest

2. Run the following command to modify the password of the ftptest user:

   passwd ftptest

   Follow the command line instructions to modify the password of the user.

3. Run the following command to create a file directory for the FTP service:

   mkdir /var/ftp/test

4. Run the following command to create a test file.

   The test file is used when the FTP client accesses the FTP server.

   touch /var/ftp/test/testfile.txt

5. Run the following command to change the owner of the /var/ftp/test directory to ftptest:

   chown -R ftptest:ftptest /var/ftp/test

6. Modify the vsftpd.conf configuration file.

   1. Run the following command to open the configuration file of vsftpd.

      If vsftpd is installed by running the apt install vsftpd command, the path of the configuration file is /etc/vsftpd.conf.

      vim /etc/vsftpd/vsftpd.conf

   2. Press the I key to enter the Insert mode.

   3. Enable passive mode for the FTP server.

      Configure the following parameters:

      Important

      When you modify or add information in the configuration file, take note of the format. For example, an extra space may cause the service to fail to restart.

      #Use the default values for parameters other than the following parameters: 
      
      #Modify the values of the following parameters:
      #Disable anonymous users from logging on to the FTP server. 
      anonymous_enable=NO
      #Allow local users to log on to the FTP server. 
      local_enable=YES
      #Listen on IPv4 sockets. 
      listen=YES
      
      #Add a number sign (#) to the beginning of the line to comment out the following parameter:
      #Disable listening on IPv6 sockets. 
      #listen_ipv6=YES
      
      #Add the following parameters to the end of the configuration file:
      #Specify the directory of a local user after the local user logs on. 
      local_root=/var/ftp/test
      #Limit all users to the home directory after the users log on. 
      chroot_local_user=YES
      #Use a list to specify exception users. Exception users are not limited to the home directory after they log on. 
      chroot_list_enable=YES
      #Specify a file to store the list of exception users. 
      chroot_list_file=/etc/vsftpd/chroot_list
      #Enable passive mode. 
      pasv_enable=YES
      allow_writeable_chroot=YES
      #Enter the public IP address of the Linux instance that is used in this topic. 
      pasv_address=<Public IP address of the FTP server>
      #Specify the lowest possible port that is sent to the FTP clients for passive mode connections. 
      We recommend that you use ports in a high range, such as 50000 to 50010. These ports provide more secure access to the FTP server. 
      pasv_min_port=<port number>
      #Specify the highest possible port that is sent to the FTP clients for passive mode connections. 
      pasv_max_port=<port number>

      For information about more parameters, see the vsftpd configuration file and parameters section in this topic.

   4. Press the Esc key, enter :wq, and then press the Enter key to save and close the configuration file.

7. Create the chroot_list file and write the list of exception users to the file.

   1. Run the following command to create the chroot_list file:

      vim /etc/vsftpd/chroot_list

   2. Press the I key to enter Insert mode.

   3. Enter the list of exception users. Exception users are not limited to the home directory and can access other directories.

   4. Press the Esc key, enter :wq, and then press the Enter key to save and close the configuration file.

   Important

   If exception users do not exist, you must still create the chroot_list file. The file can be empty.

8. Run the following command to restart vsftpd:

   systemctl restart vsftpd.service

Step 3: Configure security groups

Step 4: Check whether you can access the FTP server from the client

You can use FTP clients, Windows command-line tools, or browsers to check whether the FTP server is reachable. In this example, an on-premises host that runs a Windows Server 2012 R2 64-bit operating system is used as an FTP client to show how to access the FTP server.

1. On the on-premises host, open This Computer.

2. In the address bar, enter ftp://<Public IP address of the FTP server>:<FTP port>. In this example, the public IP address of the Linux instance is used. Example: ftp://121.43.XX.XX:21.

3. In the Log on as dialog box, enter the FTP username and password that you configured and then click Logon.

   After you log on to the FTP server, you can view the files in the specified directory on the FTP server. For example, you can view the test file named testfile.txt.

vsftpd configuration file and parameters