Mysql主从复制—5.7 gtid 双主 + Keepalived 配置及简单测试

 

参考：https://cloud.tencent.com/developer/article/1134077

 

keepalive下载：https://www.keepalived.org/download.html

 

这里主要讲keepalived配置和测试， mysql的gtid配置主从 详见 https://blog.csdn.net/fly43108622/article/details/86089178

 

说明：

master：192.168.56.80    mysqld的server_id 为222

slave   ：192.168.56.61    mysqld的server_id 为111

vip      ：192.168.56.168

 

注：maste 和slave  是gtid配置好的双主状态。

 

 

一、配置文件文件 /etc/keepalived/keepalived.conf   注释说明如下

global_defs {
   router_id MYSQL-1 //表示运行keepalived服务器的一个标识}
// 定义自动核对mysql的脚本
vrrp_script check_mysql {
    script "/etc/keepalived/bin/check_mysql.sh"
    interval 22
    weight 2   
}
vrrp_instance VI_1 {
    state BACKUP //指定keepalived的角色, 两台配置此处均是BACKUP,设为BACKUP将根据优先级决定主或从
    interface eth1 //指定HA监测网络的接口
    virtual_router_id 51 /虚拟路由标识，这个标识是一个数字(取值在0-255之间,用来区分多个instance的VRRP组播)，同一个vrrp实例使用唯一的标识,确保和master2相同，同网内不同集群此项必须不同,否则发生冲突。
    priority 100   //用来选举master的，要成为master，该项取值范围是1-255（在此范围之外会被识别成默认值100）,此处master2上设置为50
    advert_int 1 //发VRRP包的时间间隔，即多久进行一次master选举（可以认为是健康查检时间间隔）
    nopreempt //不抢占，即允许一个priority比较低的节点作为master，即使有priority更高的节点启动
    authentication {
        //认证区域，认证类型有PASS和HA（IPSEC），推荐使用PASS（密码只识别前8位）
        auth_type PASS
        auth_pass 1111
    }
    virtual_ipaddress {
        // 指定vip地址
        192.168.1.66
    }
    track_script {
        //指定核对的脚本，check_mysql是上述自定义的
        check_mysql
    }
}
virtual_server 192.168.1.66 3306 {
    delay_loop 2  //设置运行情况检查时间，单位是秒
    lb_algo rr   //设置后端调度算法，这里设置为rr，即轮询算法
    lb_kind DR //设置LVS实现负载均衡的机制，有NAT、TUN、DR三个模式可选
    persistence_timeout 50 //会话保持时间，单位是秒。这个选项对动态网页是非常有用的，为集群系统中的session共享提供了一个很好的解决方案。有了这个会话保持功能，用户的请求会被一直分发到某个服务节点，直到超过这个会话的保持时间。
    protocol TCP //指定转发协议类型，有TCP和UDP两种
    real_server 192.168.1.60 3306 {
        weight 3 //配置服务节点的权值，权值大小用数字表示，数字越大，权值越高，设置权值大小为了区分不同性能的服务器
        notify_stop /etc/keepalived/bin/shutdown.sh //检测到mysql服务down后执行的脚本，在一些版本中叫notify_down
        TCP_CHECK {
            connect_timeout 3 //连接超时时间
            nb_get_retry 3 //重连次数
            delay_before_retry 3 //重连间隔时间
            connect_port 3306 //健康检查端口
        }
    }}

 

 

二、主库上配置keepalived  master：192.168.56.80(slave备库配置同理， 只是keepalived.conf 配置文件需要略为修改，详见如下)

--解压缩
[root@hostmysql80 mysql_setup]# tar -xzvf keepalived-2.0.19.tar.gz

--修改权限
[root@hostmysql80 mysql_setup]# chown -R root:root  keepalived-2.0.19/


--新建keepalive目录
[root@hostmysql80 mysql_setup]# mkdir keepalived
[root@hostmysql80 mysql_setup]# cd keepalived-2.0.19/


--初次配置 报错 需要安装包
[root@hostmysql80 keepalived-2.0.19]# ./configure  --prefix=/mysql_setup/keepalived
*** WARNING - this build will not support IPVS with IPv6. Please install libnl/libnl-3 dev libraries to support IPv6 with IPVS.

--安装libnl/libnl-3
[root@hostmysql80 mysql_setup]# rpm -ivh libnl-devel-1.1.4-3.el7.x86_64.rpm
Preparing...                          ################################# [100%]
Updating / installing...
   1:libnl-devel-1.1.4-3.el7          ################################# [100%]
[root@hostmysql80 mysql_setup]# rpm -ivh libnl3-devel-3.2.28-4.el7.x86_64.rpm
Preparing...                          ################################# [100%]
Updating / installing...
   1:libnl3-devel-3.2.28-4.el7        ################################# [100%]
[root@hostmysql80 mysql_setup]#


--再次配置  成功
[root@hostmysql80 keepalived-2.0.19]# ./configure  --prefix=/mysql_setup/keepalived-2.0.19

--编译&安装
[root@hostmysql80 keepalived-2.0.19]# make && make install


--注册系统服务
[root@hostmysql80 keepalived]# cp /mysql_setup/keepalived/sbin/keepalived /usr/sbin/
[root@hostmysql80 keepalived]# cp /mysql_setup/keepalived/etc/sysconfig/keepalived  /etc/sysconfig/
[root@hostmysql80 keepalived]# cp /mysql_setup/keepalived-2.0.19/keepalived/etc/init.d/keepalived  /etc/init.d
[root@hostmysql80 keepalived]# mkdir -p /etc/keepalived
[root@hostmysql80 keepalived]# cp /mysql_setup/keepalived/etc/keepalived/keepalived.conf  /etc/keepalived/


--修改keepalived的systemctl 服务
[root@hostmysql80 ~]# vi /lib/systemd/system/keepalived.service

[Unit]
Description=LVS and VRRP High Availability Monitor
After=network-online.target syslog.target
Wants=network-online.target

[Service]
Type=forking
PIDFile=/run/keepalived.pid
KillMode=process
EnvironmentFile=/etc/sysconfig/keepalived
ExecStart=/usr/sbin/keepalived $KEEPALIVED_OPTIONS
ExecReload=/bin/kill -HUP $MAINPID

[Install]
WantedBy=multi-user.target


--生效新配置keepalived的systemctl 服务
[root@hostmysql80 mysql_setup]# systemctl daemon-reload



--编辑keepalived.conf配置文件
[root@hostmysql80 keepalived]# pwd
/etc/keepalived

[root@hostmysql80 keepalived]# vi keepalived.conf

! Configuration File for keepalived

global_defs {
   router_id MYSQL-M               //备库改为MYSQL-S
}

vrrp_script check_mysql {
   script "/etc/keepalived/bin/check_mysql.sh"
   interval 2
   weight 2
}

vrrp_instance VI_1 {
    state BACKUP
    interface enp0s3
    virtual_router_id 51
    priority 100                    //备库改为50  权重
    advert_int 1
    nopreempt
    authentication {
        auth_type PASS
        auth_pass 1111
    }
    unicast_src_ip 192.168.56.80    //备库改ip(为本机ip)
    unicast_peer {
        192.168.56.61               //备库改ip(为对端ip)
    }
    virtual_ipaddress {
        192.168.56.168
    }
    track_script {
        check_mysql
    }
}

virtual_server 192.168.56.168 3306 {
    delay_loop 2
    lb_algo rr
    lb_kind DR
    persistence_timeout 50
    protocol TCP

    real_server 192.168.56.80 3306 {     //备库改ip(为本机ip)
        weight 3
        notify_stop "/etc/keepalived/bin/shutdown.sh"
        TCP_CHECK {
            connect_timeout 3
            nb_get_retry 3
            delay_before_retry 3
            connect_port 3306
        }
    }
}



--建立check_mysql.sh check文件  ，用来检测在mysqld服务没有时 关闭本地keepalived服务 让vip指向其他real ip 
[root@localmysql-source keepalived]# pwd
/etc/keepalived
[root@hostmysql80 keepalived]# mkdir bin
[root@hostmysql80 keepalived]# cd bin
[root@hostmysql80 bin]# vi check_mysql.sh


#!/bin/bash
MYSQL_HOST=localhost
MYSQL_USER=root
MYSQL_PASSWORD=Root123$


mysql -h $MYSQL_HOST -u $MYSQL_USER -p$MYSQL_PASSWORD -e "show status;" >/dev/null 2>&1
if [ $? == 0 ]
then
    echo " $host mysql login successfully "
    exit 0
else
    service keepalived stop
    exit 2
fi



--建立shutdown.sh 文件
[root@localmysql-source bin]# pwd
/etc/keepalived/bin
[root@hostmysql80 bin]# vi shutdown.sh


#!/bin/bash
service keepalived stop



--执行权限
[root@localmysql-source bin]# chmod +x /etc/keepalived/bin/check_mysql.sh
[root@localmysql-source bin]# chmod +x /etc/keepalived/bin/shutdown.sh



--启动keepalived
[root@hostmysql80 keepalived]# service keepalived start
Redirecting to /bin/systemctl start keepalived.service


--查看keepalived状态
[root@hostmysql80 keepalived]# service keepalived status
Redirecting to /bin/systemctl status keepalived.service
鈼?[0m keepalived.service - LVS and VRRP High Availability Monitor
   Loaded: loaded (/usr/lib/systemd/system/keepalived.service; disabled; vendor preset: disabled)
   Active: active (running) since Fri 2019-10-25 16:36:09 CST; 4s ago
  Process: 3178 ExecStart=/mysql_setup/keepalived/sbin/keepalived $KEEPALIVED_OPTIONS (code=exited, status=0/SUCCESS)
Main PID: 3179 (keepalived)
    Tasks: 3
   CGroup: /system.slice/keepalived.service
           鈹溾攢3179 /mysql_setup/keepalived/sbin/keepalived -D
           鈹溾攢3180 /mysql_setup/keepalived/sbin/keepalived -D
           鈹斺攢3181 /mysql_setup/keepalived/sbin/keepalived -D


Oct 25 16:36:11 hostmysql80 Keepalived_healthcheckers[3180]: TCP connection to [192.168.56.80]:tcp:3306 success.
Oct 25 16:36:12 hostmysql80 Keepalived_vrrp[3181]: (VI_1) Receive advertisement timeout
Oct 25 16:36:13 hostmysql80 Keepalived_vrrp[3181]: (VI_1) Entering MASTER STATE
Oct 25 16:36:13 hostmysql80 Keepalived_vrrp[3181]: (VI_1) setting VIPs.
Oct 25 16:36:13 hostmysql80 Keepalived_vrrp[3181]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 25 16:36:13 hostmysql80 Keepalived_vrrp[3181]: (VI_1) Sending/queueing gratuitous ARPs on enp0s3 for 192.168.56.168
Oct 25 16:36:13 hostmysql80 Keepalived_vrrp[3181]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 25 16:36:13 hostmysql80 Keepalived_vrrp[3181]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 25 16:36:13 hostmysql80 Keepalived_vrrp[3181]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 25 16:36:13 hostmysql80 Keepalived_vrrp[3181]: Sending gratuitous ARP on enp0s3 for 192.168.56.168



--查看ip，有vip出现192.168.56.168
[root@hostmysql80 keepalived]# ip addr
1: lo:  mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host
       valid_lft forever preferred_lft forever
2: enp0s3:  mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 08:00:27:78:13:79 brd ff:ff:ff:ff:ff:ff
    inet 192.168.56.80/24 brd 192.168.56.255 scope global noprefixroute enp0s3
       valid_lft forever preferred_lft forever
    inet 192.168.56.168/32 scope global enp0s3
       valid_lft forever preferred_lft forever
    inet6 fe80::fb26:9506:8c30:d55d/64 scope link noprefixroute
       valid_lft forever preferred_lft forever
3: virbr0:  mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:71:1f:75 brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
4: virbr0-nic:  mtu 1500 qdisc pfifo_fast master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:71:1f:75 brd ff:ff:ff:ff:ff:ff
[root@hostmysql80 keepalived]#

 

 

 

三、测试流程：

--1、说明
1：master(192.168.56.80)和slave (192.168.56.61)，都开启keepalived，此时连接vip的mysqld为master(192.168.56.80)    因为master上keepalived配置的priority大
2：在master(192.168.56.80)上停止mysqld服务(systemctl stop mysqld.service) ，当master(192.168.56.80)的check_mysql.sh 检测到mysqld服务停止时，会停止掉master(192.168.56.80)的keepalived。
3：此时keepalived的实例会漂移到另一个节点上，也就是slave (192.168.56.61)的keepalived会开启，
4：此时连接vip的mysqld为slave (192.168.56.61)， 建立测试表插入数据 (create table  t_20191030_slave_61(a int) ;  insert into t_20191030_slave_61 values(1);)  这时slave库有数据但master库没有
5：master(192.168.56.80)修复好后，启动master的mysqld和keepalived  (systemctl start mysqld.service    systemctl start keepalived.service)
6：由于keepalived不是抢占模式(nopreempt)，需要让slave (192.168.56.61)的keepalived停掉(systemctl stop keepalived.service)，这样vip回切到master(192.168.56.80)
7：查看master(192.168.56.80) 是有t_20191030_slave_61表 且有数据(select * from t_20191030_slave_61;)，回切成功 且 停掉时间段的数据无丢失。


--2、流程

--master(192.168.56.80) 的mysqld和keepalived 状态 都是开启，并且现在keepalived在master上
[root@hostmysql80 ~]# systemctl status mysqld.service

[root@hostmysql80 ~]# systemctl status keepalived.service



--slave(192.168.56.61) 的mysqld和keepalived 状态 都是开启，但现在keepalived不在slave上
[root@hostmysql61 ~]# systemctl status mysqld.service

[root@hostmysql61 ~]# systemctl status keepalived.service

--现在连接vip 192.168.56.168 是server_id 222的，也就是master上的id

 

--停掉master(192.168.56.80)的mysqld服务后，因为check_mysql.sh自动检测脚本，也会关闭keepalived服务，使得real ip 漂移到可用的节点上(这里为slave(192.168.56.61) 节点)
[root@hostmysql80 keepalived]# systemctl stop mysqld.service
[root@hostmysql80 ~]# systemctl status keepalived.service


--此时查看slave(192.168.56.61)，发现keepalived已漂移过来，
[root@hostmysql61 ~]# systemctl status keepalived.service

 

--现在连接vip 192.168.56.168 是server_id 111的，也就是slave上的id，漂移成功

 

--vip现在 连接的是slave库 ，建立测试表并插入数据

 

--修复master操作，手动启动master库的mysqld和keepalived
[root@hostmysql80 ~]# systemctl start mysqld.service
[root@hostmysql80 ~]#  systemctl status mysqld.service

[root@hostmysql80 ~]# systemctl start keepalived.service
[root@hostmysql80 ~]#  systemctl status keepalived.service


--回切操作，停掉slave库的keepalived
[root@hostmysql61 ~]# systemctl stop keepalived.service
[root@hostmysql61 ~]# systemctl status keepalived.service

 

--此时vip成功回切到master (master库的server_id为222 )

 

--vip现在 连接的是master库 ，刚才在slave库创建的测试表可以查询出数据，master停掉期间内的数据同步成功

 

 

四、配置keepalived单独的日志文件

--1、修改/etc/sysconfig/keepalived，从KEEPALIVED_OPTIONS="-D" 改为 KEEPALIVED_OPTIONS="-D -d -S 0"
[root@hostmysql80 ~]# vi /etc/sysconfig/keepalived
# Options for keepalived. See `keepalived --help' output and keepalived(8) and
# keepalived.conf(5) man pages for a list of all options. Here are the most
# common ones :
#
# --vrrp               -P    Only run with VRRP subsystem.
# --check              -C    Only run with Health-checker subsystem.
# --dont-release-vrrp  -V    Dont remove VRRP VIPs & VROUTEs on daemon stop.
# --dont-release-ipvs  -I    Dont remove IPVS topology on daemon stop.
# --dump-conf          -d    Dump the configuration data.
# --log-detail         -D    Detailed log messages.
# --log-facility       -S    0-7 Set local syslog facility (default=LOG_DAEMON)
#

KEEPALIVED_OPTIONS="-D -d -S 0"



--2、修改/etc/rsyslog.conf文件 ，最后增加 local0.*    /var/log/keepalived.log
[root@hostmysql80 ~]# vi /etc/rsyslog.conf
#keepalived#
local0.*                                                /var/log/keepalived.log

--重启rsyslog和keepalived
[root@hostmysql80 ~]# systemctl restart rsyslog.service
[root@hostmysql80 ~]# systemctl restart keepalived.service

--查看/var/log/keepalived.log 文件有日志生成
[root@hostmysql80 ~]# tail -10 /var/log/keepalived.log
Oct 29 17:25:36 hostmysql80 Keepalived_vrrp[2701]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 29 17:25:36 hostmysql80 Keepalived_vrrp[2701]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 29 17:25:36 hostmysql80 Keepalived_vrrp[2701]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 29 17:25:36 hostmysql80 Keepalived_vrrp[2701]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 29 17:25:41 hostmysql80 Keepalived_vrrp[2701]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 29 17:25:41 hostmysql80 Keepalived_vrrp[2701]: (VI_1) Sending/queueing gratuitous ARPs on enp0s3 for 192.168.56.168
Oct 29 17:25:41 hostmysql80 Keepalived_vrrp[2701]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 29 17:25:41 hostmysql80 Keepalived_vrrp[2701]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 29 17:25:41 hostmysql80 Keepalived_vrrp[2701]: Sending gratuitous ARP on enp0s3 for 192.168.56.168
Oct 29 17:25:41 hostmysql80 Keepalived_vrrp[2701]: Sending gratuitous ARP on enp0s3 for 192.168.56.168