Hi Mark, On Jun 4, 2015, at 8:18 AM, 8 <421174439@qq.com> wrote:

A python process listen on port 4001, and there is clients connected to it and play some chess game. but strangely, One more than two days later, there may be one or two more other process listen on the same port 4001 which block the data which should send to my python server.

Unfortunately this is not nearly enough information to diagnose the issue. What messages do you see in your logs? When is your process re-started? If it isn't re-started, how did it lose access to the socket it was already listening on?

I use the "sudo netstat -antup" intented to find the process ID, but that newly created process listening on port 4001 has no pid or pname.

This doesn't make sense. By definition, processes on Linux have PIDs.

And when I try to kill the initial python server process listening on port 4001 using command kill pid, after exected the kill command, I use netstat -antup again, suprisingly, I found that process which should be killed are still alive.

And this makes even less sense - how can you kill a PID if there is no PID?

Then I use command kill -9 pid to kill it, then execute netstat - antup commnd, all the process listening on port 4001 disappeared.

Would u please kindly give me any answer?

I hope we can get to the bottom of this but we will definitely need more information. As it is I have no idea what is happening, let alone why. -glyph