Checking if a Port is Open

[Jake Colman]

My ISP has threatened to close the smtp port (25) to prevent commercial users
from using the residential cable.  I am running sendmail and can use
check_smtp to ensure that the server is up and running on my host. Is there
anything I can monitor to ensure that sendmail can be accessed from the
outside world?

More generally, is there I can use to monitor whether specific ports are open
to the outside and have nagios flag it if server on that port cannot be
reached?


-- 
Jake Colman                     

Principia Partners LLC                  Phone: (201) 209-2467
Harborside Financial Center               Fax: (201) 946-0320
902 Plaza Two                          E-mail: colman at ppllc.com
Jersey City, NJ 07311                  www.principiapartners.com


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