title: Testing a telnet connectivity for multiple servers from a file
body: <p>I have a file with 10 servers (one per line) and I need to check from time to time if telnet on port 1231 is opened.</p>
  
  <p>How can I do that using a bash script?</p>
  
  <p>I tried to find a similar topic related to my question on other topics, but I didn't find anything.</p>