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        Verifying ports are listening

Section(s): Security , Network
Published on Jun 26, 2007.
Last Modified on Jun 26, 2007.
Last Modified by Mitch Tulloch.
Rating: Not Rated

How to determine if a server is listening on a given port.

In the old days of server troubleshooting, we used to use Telnet to check whether our SMTP server was listening on port 25, our HTTP server was listening on port 80, and so on. Open a Telnet session and type a few appropriate commands and you’d get a response (or not). Nowadays however we have LDAP ports and all kinds of ports and who knows what commands these ports respond to? How can you verify then whether a particular port is listening or not on a server? PortQry 2.0 is your friend, check it out at http://support.microsoft.com/kb/832919. You’ll also find PortQry on the Companion DVD of the Windows Vista Resource Kit, see http://www.mtit.com.

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Mitch Tulloch was lead author for the Windows Vista Resource Kit from Microsoft Press, which is THE book for IT pros who want to deploy, maintain and support Windows Vista in mid- and large-sized network environments. For more information see www.mtit.com.

About Mitch Tulloch

Mitch Tulloch was lead author for the Windows Vista Resource Kit from Microsoft Press, which is the book for IT pros who want to deploy, maintain and support Windows Vista in mid- and large-sized network environments. Mitch was also the author of Introducing Windows Server 2008 and technical project lead for the Microsoft Office Communications Server 2007 Resource Kit, both books also from Microsoft Press. For more information on these and other books by Mitch, see www.mtit.com .