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I'm wondering what are the possible ways to block some port while it is in use by some other process?

Short story long: I've got an app(1) that communicates with another app(2) on one host/local machine through some port (7080). Periodically communication is being dropped or blocked or whatever, though processes are not suspended and their status report is OK. So I'm wondering how is it possible to perform such blocking and who can do it?

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up vote 1 down vote accepted

This sounds more like some kind of network outage or error than an active blocking to me.

Are these machines on the same network?

Are you connecting through the internet?

If you are going through the internet, is there NAT involved? If the connection is idle for a long time then NAT mappings could be being dropped by a router and hence the connection would break.


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Its quite complicated at that point. 1) Looks like it's not connected to an internet. 2) There's dozens of linux boxes connected to it or to network, to which that box is connected. – Denys S. Jun 9 '11 at 16:00

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