蟒蛇TCPSERVER地址我关闭服务器，我用`allow_reuse_address`

Question

这里是我的代码来运行服务器：

class MyRequestHandler(SimpleHTTPServer.SimpleHTTPRequestHandler): 
    #.... 

PORT = 8089 

httpd = SocketServer.TCPServer(("", PORT), MyRequestHandler) 
httpd.allow_reuse_address = True 

print "Serving forever at port", PORT 
try: 
    httpd.serve_forever() 
except: 
    print "Closing the server." 
    httpd.server_close() 
    raise 

然而，这是发生了什么：

^CClosing the server. 
Traceback (most recent call last): 
    File "server.py", line 118, in <module> 
    self.send_error(400, "Unimplemented GET command: %s" % (self.path,)) 
    File "/home/claudiu/local/lib/python2.6/SocketServer.py", line 224, in serve_forever 
    r, w, e = select.select([self], [], [], poll_interval) 
KeyboardInterrupt 
(.virtualenv)claudiu@xxx:~/xxx$ python server.py 
Traceback (most recent call last): 
    File "server.py", line 122, in <module> 
    httpd = SocketServer.TCPServer(("", PORT), MyRequestHandler) 
    File "/home/claudiu/local/lib/python2.6/SocketServer.py", line 402, in __init__ 
    self.server_bind() 
    File "/home/claudiu/local/lib/python2.6/SocketServer.py", line 413, in server_bind 
    self.socket.bind(self.server_address) 
    File "<string>", line 1, in bind 
socket.error: [Errno 98] Address already in use 

为什么？我关闭服务器并将allow_reuse_address设置为True ...使用python 2.6.8。

Answer 1

感谢其他答案，我找到了答案。 allow_reuse_address应该在类，而不是实例：

SocketServer.TCPServer.allow_reuse_address = True 
httpd = SocketServer.TCPServer(("", PORT), MyRequestHandler) 

我仍然不知道为什么关闭套接字没有释放它的服务器在下次运行，虽然。

Answer 2

这是因为TCP TIME_WAIT。

Somebody discovered this exact problem.

However, if I try to stop and start the server again to test any modifications, I get a random “socket.error: [Errno 98] Address already in use” error. This happens only if a client has already connected to the server.

Checking with netstat and ps, I found that although the process it self is no longer running, the socket is still listening on the port with status “TIME_WAIT”. Basically the OS waits for a while to make sure this connection has no remaining packets on the way.

Answer 3

这是因为你必须设置SO_REUSEADDRESS 绑定套接字之前。由于您只需一步创建和绑定套接字，然后进行设置，现在已经太晚了。

Answer 4

的[Err 98] Address already in use是由于插座是.close()但它仍然在等待足够的时间来传递，以确保远程TCP接收到它的连接终止请求的确认（见TIME_WAIT）。默认情况下，你不能将套接字绑定，如果有一个套接字绑定到端口，但是你可以重写与allow_reuse_address（SO_REUSEADDR）

虽然是可能的变异TCPServer.allow_reuse_addr（如this other answer提出的），我认为是更干净你自己的TCPServer子类，其中allow_reuse_address设置为True：

import SocketServer 
import SimpleHTTPServer 
import time 

class MyRequestHandler(SimpleHTTPServer.SimpleHTTPRequestHandler): 
    def do_GET(): 
     time.sleep(60) 
     self.request.sendall("I'm here!") 

class ReuseAddrTCPServer(SocketServer.TCPServer): 
    allow_reuse_address = True 

PORT = 8089 

httpd = ReuseAddrTCPServer(("", PORT), MyRequestHandler) 
httpd.daemon_threads = True 


print "Serving forever at port", PORT 
try: 
    httpd.serve_forever() 
except: 
    print "Closing the server." 
    httpd.server_close() 
    raise 

您可以使用绝对设置实例本身allow_reuse_address（不带班搞乱），但你需要使用TCPServer(..., bind_and_activate=False)，否则插座会前绑定你有机会更改allow_reuse_address设置。然后，你需要serve_forever()之前手动调用.server_bind()和.server_activate()：

... 
httpd = SocketServer.TCPServer(("", PORT), MyRequestHandler, bind_and_activate=False) 
httpd.allow_reuse_address = True 
httpd.daemon_threads = True 
... 
httpd.server_bind() 
httpd.server_activate() 
httpd.serve_forever()