Create a ts3 user

  sudo adduser --disabled-login ts3

Get the latest TeamSpeak 3 server files for 64-bit Linux.

  // lets cd to the location where we want to install our ts server
  cd /opt
  wget http://dl.4players.de/ts/releases/3.1.1/teamspeak3-server_linux_amd64-3.2.3.tar.bz2

Extract the archive.

  sudo tar -xvf teamspeak3-server_linux_amd64-3.1.1.tar.bz2

In the extracted folder, we have the conditions for using Teamspeak servers. It will be necessary to accept them by creating a file before starting the server.

    cd teamspeak3-server_linux_amd64
    #Reading the Terms
    sudo nano LICENSE
    # Creation of the acceptance file
    sudo touch .ts3server_license_accepted

We will now start our server for the first time. At the first start of the server, we will have access to very important information, which will allow you to administer your server. It will therefore be necessary to note the connection information of the Admin Server and the Token.

    sudo sh ts3server_startscript.sh start

    ------------------------------------------------------------------
                          I M P O R T A N T                           
    ------------------------------------------------------------------
                   Server Query Admin Account created                 
             loginname= "serveradmin", password= "xxxxxxxx"
    ------------------------------------------------------------------

    ------------------------------------------------------------------
                          I M P O R T A N T                           
    ------------------------------------------------------------------
          ServerAdmin privilege key created, please use it to gain 
          serveradmin rights for your virtualserver. please
          also check the doc/privilegekey_guide.txt for details.

           token=xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
    ------------------------------------------------------------------

Make the TeamSpeak 3 server start on boot. Use your favorite editor to make a new file called teamspeak in /etc/init.d/.

  sudo nano /etc/init.d/ts3

Populate it with this content.

  #!/bin/sh
  ### BEGIN INIT INFO
  # Provides:         teamspeak
  # Required-Start:   $local_fs $network
  # Required-Stop:    $local_fs $network
  # Default-Start:    2 3 4 5
  # Default-Stop:     0 1 6
  # Description:      Teamspeak 3 Server
  ### END INIT INFO

  ######################################
  # Customize values for your needs: "User"; "DIR"

  USER="ts3"
  DIR="/opt/teamspeak3-server_linux_amd64"

  ###### Teamspeak 3 server start/stop script ######

  case "$1" in
  start)
  su $USER -c "${DIR}/ts3server_startscript.sh start"
  ;;
  stop)
  su $USER -c "${DIR}/ts3server_startscript.sh stop"
  ;;
  restart)
  su $USER -c "${DIR}/ts3server_startscript.sh restart"
  ;;
  status)
  su $USER -c "${DIR}/ts3server_startscript.sh status"
  ;;
  *)
  echo "Usage: {start|stop|restart|status}" >&2
  exit 1
  ;;
  esac
  exit 0

Once you are done, save the file and close the editor.

Make it executable and add it to the service.

 sudo chmod +x /etc/init.d/ts3
 sudo update-rc.d ts3 defaults

Make sure to change teamspeak folder ownership to ts3 user

sudo chown -R ts3:ts3 /opt/teamspeak3-server_linux_amd64

Fail2ban configuration

create a teamspeak.conf filter on your /etc/fail2ban/filter.d

  sudo nano /etc/fail2ban/filter.d/teamspeak.conf
  
  // populate it with this content
  [INCLUDES]
  before = common.conf
  [Definition]
  failregex = ^(.*)query from [0-9]{1,} :[0-9]{1,5} attempted to login with account "(.*)" and failed!$
  ignoreregex =

Make sure to enable all logs on your teamspeak server configuration

Now add your filter to the jail.local fail

   sudo nano /etc/fail2ban/jail.local
   
   add this rules to your file
   
   [teamspeak]
   enabled  = true
   port     = 9987,10011,30033
   filter   = teamspeak
   logpath  = /opt/ts3/teamspeak3-server_linux_amd64/logs/ts3server_*.log
   maxretry = 3
   bantime  = 86400
   findtime = 7800

Now check if our teamspeak filter is working by running the following commands:

 // this command will list all the enabled filters
 sudo fail2ban-client status 
 
 // this command will load the status of teamspeak filter and additional details
 sudo fail2ban-client status teamspeak