HEELPBOOK - Networking - How to test HTTP (Port 80) using Telnet ################## Telnet is a long-time favorite for troubleshooting connection issues. It can be used to attempt to connect to a server on a given port. Generally you can quickly ascertain whether sometime is "listening" on the remote side-which will confirm that: (1) you can get to the remote server from your test box, and... (2) that a server is running and bound to the specified port you requested. More specifically, telnet can be used to test HTTP scenarios, effectively stripping through all the friendly layers a browser usually hides from web visitor eyes. Troubleshooting HTTP using telnet is a great way to review exactly what is getting returned to your browser during a web request for a particular url. This allows you to see headers and collect other information related to the web server. Here is a simple example making an HTTP 1.1 request. First, get to a command prompt. For example, if you are using Windows, Start -> Run -> cmd. (Though if you are using Windows, you may want to use something like CYGWIN, or Putty rather than the DOS prompt). ######## INPUT: >telnet www.esqsoft.globalservers.com 80 Note: this launches telnet and tells it to look up and connect to the server for "www.esqsoft.globalservers.com" on port 80. ###### OUTPUT: Trying 64.136.56.122... Connected to www.esqsoft.globalservers.com. Escape character is '^]'. ###### INPUT: GET /index.htm HTTP/1.1 host: www.esqsoft.globalservers.com Notes: 1) no OS cursor caret, the connection is open so you just get a blank line waiting for input. 2) need to hit twice after the "host:" ##### OUTPUT: HTTP/1.1 200 OK Date: Mon, 18 Apr 2005 16:38:00 GMT Server: Apache/1.3.27 (Unix) (Red-Hat/Linux) mod_ssl/2.8.12 OpenSSL/0.9.6 PHP/4.1.2 mod_perl/1.27 FrontPage/5.0.2.2623 Last-Modified: Thu, 01 Jul 2004 01:16:05 GMT ETag: "158e008c-182c-40e365d5" Accept-Ranges: bytes Content-Length: 6188 Connection: close Content-Type: text/html ...big long nasty HTML code here... ############ ARTICLE INFO ############# Article Month: May Article Date: 03/05/2012 Permalink: http://heelpbook.altervista.org/2012/networking-how-to-test-http-port-80-using-telnet/ Source: http://www.esqsoft.com/examples/troubleshooting-http-using-telnet.htm Language: English View more articles on: http://www.heelpbook.net/ Follow us on Facebook: http://it-it.facebook.com/pages/HeelpBook/100790870008832 Follow us on Twitter: https://twitter.com/#!/HeelpBook Follow us on RSS Feed: http://feeds.feedburner.com/Heelpbook Follow us on Delicious: http://delicious.com/heelpbook