Any tool to check which ports/protocols firewalls prevent?

Posted by Jus12 on Server Fault See other posts from Server Fault or by Jus12
Published on 2011-02-09T15:08:24Z Indexed on 2011/02/09 15:27 UTC
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Filed under:

firewall

|

port

Suppose I have a setup as:

host_1 --- Firewall_1 --- Internet --- Firewall_2 --- host_2

I need to check which ports are open on host_2 from host_1 (which may be blocked by either firewalls)

If there a tool that comes in two parts (one running on host_1 and other on host_2) that does this for me? It should be something like:

1 Listen to all ports on host_2
2 Try to connect to every port on host_2 from host_1
3 Give a report what ports are allowed.

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