Experiment - 70 :- Working with SMTP, TELNET, FTP, HTP, SNMP, LDAP etc

 

Objective:

To demonstrate the functionality of various network protocols (SMTP, TELNET, FTP, HTTP, SNMP, and LDAP) in a controlled environment.

Requirements:

• A Linux server (Ubuntu or CentOS) with the following services installed:
  • SMTP server (Postfix)
  • FTP server (vsftpd)
  • Web server (Apache or Nginx)
  • SNMP server (Net-SNMP)
  • LDAP server (OpenLDAP)
• A client machine (could be the same as the server) with:
  • Telnet client
  • FTP client (command line or GUI)
  • cURL or wget for HTTP requests
  • SNMP tools (snmpget, snmpwalk)
  • LDAP tools (ldapsearch)

Procedure:

1. Set Up the Environment:

   • Ensure all services are installed and running on the server.
   • For example, you can install the services on Ubuntu using:

     bash
     1sudo apt-get update
     2sudo apt-get install postfix vsftpd apache2 snmpd slapd ldap-utils

2. Configure Each Service:

   • SMTP (Postfix):

     • Configure Postfix to allow sending emails. Edit /etc/postfix/main.cf and set:

       bash
       1myhostname = yourdomain.com
       2mydestination = localhost

     • Restart Postfix:

       bash
       1sudo systemctl restart postfix

   • FTP (vsftpd):

     • Edit /etc/vsftpd.conf to allow local users and enable write access:

       bash
       1local_enable=YES
       2write_enable=YES

     • Restart vsftpd:

       bash
       1sudo systemctl restart vsftpd

   • HTTP (Apache):

     • Place an HTML file in /var/www/html/ to serve as a test page.
     • Restart Apache:

       bash
       1sudo systemctl restart apache2

   • SNMP (Net-SNMP):

     • Edit /etc/snmp/snmpd.conf to set the community string:

       bash
       1rocommunity public

     • Restart SNMP:

       bash
       1sudo systemctl restart snmpd

   • LDAP (OpenLDAP):

     • Configure OpenLDAP and add a test entry. You can use ldapadd to add entries to your directory.

3. Experiment with Each Protocol:

   • SMTP:

     • Open a terminal and connect to the SMTP server:

       bash
       1telnet localhost 25

     • Send a test email:

       1HELO yourdomain.com
       2MAIL FROM:<your_email@yourdomain.com>
       3RCPT TO:<recipient_email@recipientdomain.com>
       4DATA
       5Subject: Test Email
       6This is a test email sent using SMTP commands.
       7.
       8QUIT

   • TELNET:

     • Connect to the server using Telnet:

       bash
       1telnet localhost 23

     • Execute a simple command (if a Telnet server is running).

   • FTP:

     • Connect to the FTP server:

       bash
       1ftp localhost

     • Log in with your credentials and upload/download a file:

       bash
       1put testfile.txt
       2get testfile.txt
       3bye

   • HTTP:

     • Use curl to make a GET request:

       bash
       1curl -I http://localhost

     • Make a POST request (if you have an API set up):

       bash
       1curl -X POST -d "param1=value1&param2=value2" http://localhost/api

   • SNMP:

     • Use snmpwalk to query the SNMP server:

       bash
       1snmpwalk -v 2c -c public localhost

   • LDAP:

     • Use ldapsearch to query the LDAP directory:

       bash
       1ldapsearch -x -b "dc=yourdomain,dc=com" "(uid=username)"

4. Document Results:

   • Record the output from each command and any observations you make during the experiments.

5. Clean Up:

   • After completing the experiments, ensure to stop any services if they are not needed:

     bash
     1sudo systemctl