discovering a service behind a nated network

From: linux user (linuxteam_at_gmail.com)
Date: 09/04/04

  • Next message: Teo Gomez: "RE: a tool like nestat" 
    Date: Sat, 4 Sep 2004 15:54:45 +0300
To: security-basics@securityfocus.com

    Hiya All,
     
    I would like to discover if a service that is behind a NATed network
    is still working, for
    example if a web server is in a private network, Nated behind a
    gateway, how could i from an external network check if the server is
    down/ or there are network problems between the server and the
    gateway? is there a way to use a tool such as traceroute for
    NATed/Firewalled network from an external link?

    The reason i am asking this is because i have been asked that
    question on a job interview, and i did not know what the correct
    answer was, it was related to a web cluster farm then.

    another reason is howto troubleshoot a service that has been port forwarded from
    the gateway, the port forwarding works for other services, but this
    specific service is not reachable, and you can not tell whether the NATed box
    was down, or the route was down, or what, you could debate that you
    can use ssh to
    the gateway server, but then that is run by a different dept. and you
    have no access to that.

    sorry if my English langauge is a bit rusty

    TIA

    Anst

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  • Next message: Teo Gomez: "RE: a tool like nestat"

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