mysql数据库主从正常切换IP脚本

       此脚本主要用于mysql数据库主从在正常情况下，因某种原因需要切换IP的情况下使用，主要就是切换IP，主要是通过内网切换公网IP，脚本代码如下：

 

#!/usr/bin/env python
# -*- coding: utf-8 -*-
#script used in Slave Server for change server ip
import os,sys,time,socket,paramiko,MySQLdb

def mysql_connect(ip,sql):#数据库连接
    try:
        conn = MySQLdb.connect(host = ip,user = 'repl',passwd = 'VQrtetr8',connect_timeout=5)
        cursor = conn.cursor(cursorclass = MySQLdb.cursors.DictCursor)
        cursor.execute(sql)
        alldata = cursor.fetchall()
        return alldata
    except MySQLdb.Error,e:
        return e.args[0]

def ssh_conm(conm):#连接主库服务器并执行命令
    host = mysql_connect('127.0.0.1',"show slave status")[0]["Master_Host"]
    #stat = mysql_chcek(host)
    username='root'
    password = '3141315'
    port = 63008
    s=paramiko.SSHClient()
    s.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    s.connect(host,port,username,password)
    stdin,stdout,stderr=s.exec_command(conm)
    result = stdout.read()
    s.close()
    return result

def log_pos():#获取当前主从的同步位置
    result = mysql_connect('127.0.0.1',"show slave status")
    host = result[0]["Master_Host"]
    s_log = result[0]["Relay_Master_Log_File"].split('.')[1]
    s_pos = result[0]["Exec_master_log_pos"]
    result = mysql_connect(host,"show master status")
    if result == 2003:#这里是应对mysql数据库无法连接，可以选择据继续和终止脚本
        choose = raw_input('Can not connect Master,Do you go on ?  (y or n) :')
        if choose == 'y':
            return 0,0,0,0
        else:
            sys.exit(1)
    m_log = result[0]["File"].split('.')[1]
    m_pos = result[0]["Position"]
    return s_log,m_log,s_pos,m_pos

def show():#循环5次判断主从同步是否一致
    print "Check Master-Slave now..."
    for i in range(5):
        s_log,m_log,s_pos,m_pos = log_pos()
        if s_log == m_log and s_pos == m_pos:
            print "Slave and Master is OK."
            break
        else:
            print "Slave and Master not OK,please wait moment."
            if i == 4:
                #print "Must be show Replcation Error,Quit this script now !"
                choose = raw_input('Master-slave not synchronous,Do you go on ?  (y or n) :')
                if choose == 'y':
                    break
                else:
                    sys.exit(1)
            i = i + 1
            time.sleep(5)

def replace():
    #显示当前主从的IP,并检测主从3306是否存在
    print "Before switching IP:"
    s_ip = os.popen("cat /etc/sysconfig/network-scripts/ifcfg-eth0|grep IPADDR|awk -F '=' '{print $2}'").read().split()[:1][0]
    print "s_ip: " + s_ip
    conm = "cat /etc/sysconfig/network-scripts/ifcfg-eth0|grep IPADDR|awk -F '=' '{print $2}'"
    m_ip = ssh_conm(conm).split()[:1][0]
    print "m_ip: " + m_ip
    print
    #1：停用主的网卡
    conm = "ifdown eth0"
    ssh_conm(conm)
    #2: 判断主从同步是否一致，如果一致则切换，不一致则手动查看问题所在（不一致的情况重复检测5次，间隔5s，检测五次依然不同步可以选择停止脚本的执行或继续执行）
    show()
    #3：修改从IP为主的IP
    os.popen("sed -i 's/%s/%s/' /etc/sysconfig/network-scripts/ifcfg-eth0" % (s_ip,m_ip))
    print "Slave change IP is OK"
    #4：修改主IP为从的IP
    conm = "sed -i 's/%s/%s/' /etc/sysconfig/network-scripts/ifcfg-eth0" % (m_ip,s_ip)
    ssh_conm(conm)
    print "Master change IP is OK"
    #5: 显示替换之后主从的IP
    print
    print "After switching IP:"
    s_ip = os.popen("cat /etc/sysconfig/network-scripts/ifcfg-eth0|grep IPADDR|awk -F '=' '{print $2}'").read().split()[:1][0]
    print "s_ip: " + s_ip
    conm = "cat /etc/sysconfig/network-scripts/ifcfg-eth0|grep IPADDR|awk -F '=' '{print $2}'"
    m_ip = ssh_conm(conm).split()[:1][0]
    print "m_ip: " + m_ip
    #6: 停止主从同步
    mysql_connect("127.0.0.1","slave stop")
    print "Slave stop OK"
    #7: 重启用主从的网卡
    print
    print "Network service restart now,please wait ......"
    conm = "ifup eth0"
    ssh_conm(conm)
    os.system("ifdown eth0")
    os.system("ifup eth0")
    print "Network reatrt OK !"

if __name__ == "__main__":
    replace()