Python异步套接字，端口无法重用

Question

This is my server code, I have already written self.set_reuse_addr() :

class ImageServer(asyncore.dispatcher):
    def __init__(self,port):
        asyncore.dispatcher.__init__(self)
        self.client = None      
        self.port = port 
        self.clientSocket = None
        self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
        self.set_reuse_addr()
        self.bind(("192.168.11.2",self.port))
        self.listen(20)
        print "[*] Listening ..."

still got this error , port reuse

self.bind(("192.168.11.2",self.port))

File "/usr/lib/python2.7/asyncore.py", line 342, in bind
return self.socket.bind(addr)

File "/usr/lib/python2.7/socket.py", line 228, in meth
return getattr(self._sock,name)(*args)

socket.error: [Errno 98] Address already in use

Is there anyone know how to fix this problem?

Answer 1

With SO_REUSEADDR :

1. ALLOW binding to 0.0.0.0:port AND 192.168.11.2:port
2. ALLOW binding to a socket in TIME_WAIT BUT you can't establish a connection to the same destination addr:port that the previous TIME_WAIT socket was.

SO_REUSEPORT will allow to do that (reuse the addr:port for multiple processes) with the caveat that a client CONNECT might result in EADDRINUSE since it can't distinguish between old socket info and new one.

sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)