Here’s a quick and easy way to figure out what kind of web server a website is using with good, old telnet. I like this method as most operating systems (both old and new versions) have a telnet client already installed.

Steps:

1. Open a command/terminal window.

2. Telnet to the server/website on port 80, e.g.

telnet www.glucosetracker.net 80

3. Type the following once you’re connected:

HEAD / HTTP/1.0

4. Hit the Enter key twice.

That’s pretty much it. You can get the web server in use, version, and operating system that the website is running on. Here’s a sample output:

Trying 162.242.213.211…
Connected to www.glucosetracker.net.
Escape character is ‘^]’.
HEAD / HTTP/1.0


HTTP/1.1 301 Moved Permanently
Server: nginx/1.2.6 (Ubuntu)
Date: Tue, 25 Mar 2014 02:21:00 GMT
Content-Type: text/html
Content-Length: 193
Connection: close
Location: https://www.glucosetracker.net/

Note that the response of the website here returns a 301 (permanent redirect) as the web server automatically redirects to https (which shows next to Location).