7、FIN-WAIT-2

7、FIN-WAIT-2

处于 FIN-WAIT-1状态的连接收到 ACK 确认包以后进入FIN-WAIT-2状态，这个时候主动关闭方的 FIN 包已经被对方确认，等待被动关闭方发送 FIN 包。

客户端超时关闭,服务端在正在处理,没法关闭,客户端处于FIN-WAIT-2

客户端:
node2:/root#netstat -an | grep 8080
tcp        0      0 192.168.137.3:57075         192.168.137.2:8080          FIN_WAIT2  


node2:/root/test#cat t19.py 
import socket
import time
import struct
s = socket.socket(socket.AF_INET,socket.SOCK_STREAM)
# SEND_BUF_SIZE = 2
s.connect(("192.168.137.2",8080))
s.settimeout(10)
s.send('112233')
s.recv(999)

node2:/root/test#time python t19.py 
Traceback (most recent call last):
  File "t19.py", line 9, in <module>
    s.recv(999)
socket.timeout: timed out

real	0m10.066s
user	0m0.027s
sys	0m0.021s


服务端:

node1:/root#netstat -na | grep 8080
tcp        0      0 192.168.137.2:8080          0.0.0.0:*                   LISTEN      
tcp        1      0 192.168.137.2:8080          192.168.137.3:57075         CLOSE_WAIT 


node1:/root/test#cat t2.py 
# coding = utf-8
# -*- coding:utf-8 -*-
import socket
import time
BUFSIZE=1024
ip_port = ('192.168.137.2',8080)
s=socket.socket(socket.AF_INET,socket.SOCK_STREAM)#创建套接字
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

print("Buffer size [Before]: %d" % s.getsockopt(socket.SOL_SOCKET, socket.SO_SNDBUF))
print("Buffer size [Before]: %d" % s.getsockopt(socket.SOL_SOCKET, socket.SO_RCVBUF))
#s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
print 'alter-----------------------------------------------------------------------';
print s.getsockopt(socket.SOL_SOCKET, socket.SO_SNDBUF)
print s.getsockopt(socket.SOL_SOCKET, socket.SO_RCVBUF)
s.bind(ip_port)#绑定地址
s.listen(5)#监听链接
print('server listening8080...')
while True: #无限等待连接
    conn,addr = s.accept() #接受客户端连接
    print('接到来自%s的链接'%addr[0])
    while True: #通信循环，无限接受客户端信息
        #print conn.getpeername()
        try:
         msg = conn.recv(BUFSIZE) #接受消息的内容
         print 'xxx--------------------xxx'
         print msg
         print 'xxx--------------------xxx'
        except Exception,err:
          break
        if len(msg)==0:break  #如果 不加，已连接的客户端突然断开，recv不再阻塞，发生死循环
        print '111-----------------------111'
        print msg
        print '111-----------------------111'
        try:
         print '开始回复报文' 
         time.sleep(100)
         conn.send('response:'+msg)
        except Exception,err:
          print err
        #conn.send(msg.upper())#服务端发送消息
    conn.close()#关闭链接
s.close()#关闭套接字