文章目录
前言
目前MySQL已经成为市场上主流数据库之一，考虑到业务的重要性，MySQL数据库单点问题已成为企业网站架构中最大的隐患。随着技术的发展，MHA的出现就是解决MySQL单点的问题。另外随着企业数据量越来越庞大，数据库的压力又成为企业的另一个瓶颈，MySQL多主多从架构的出现可以减轻MySQL本身的压力。
一、MHA 概述
1.1、MHA 是什么
MHA目前在MySQL高可用方面是一个相对成熟的解决方案，它由日本DeNA公司 youshimaton（现就职于 Facebook公司）开发，是一套优秀的作为MySQL高可用性环境下故障切换和主从提升的高可用软件。在MySQL故障切换过程中，MHA能做到在0~30秒之内自动完成数据库的故障切换操作，并且在进行故障切换的过程中，MHA能在最大程度上保证数据的一致性，以达到真正意义上的高可用。
1.2、MHA 的组成
由两部分组成：MHA Manager（管理节点）和MHA Node（数据节点）。MHA Manager可以单独部署在一台独立的机器上，管理多个master-slave集群，也可以部署在一台slave节点上。MHA Node运行在每台MySQL服务器上，MHA Manager会定时探测集群中的master节点。当master出现故障时，它可以自动将最新数据的slave提升为新的master，然后将其他所有的slave重新指向新的master。整个故障转移过程应用程序完全透明。
1.3、MHA 的特点
自动故障切换过程中，MHA试图从宕机的主服务器上保存二进制日志，最大程度的保证数据的不丢失
使用半同步复制，可以大大降低数据丢失的风险
目前MHA支持一主多从架构，最少三台服务，及一主两从
二、MHA 实验
2.1、案例环境
服务器 CentOS7.6(64 位) MHA-manager/20.0.0.21
管理节点，安装 manager 组件
服务器 CentOS7.6(64 位) Mysql1/20.0.0.25 Master 节点，安装 node 组件
服务器 CentOS7.6(64 位) Mysql2/20.0.0.23 Slave 节点，安装 node 组件
服务器 CentOS7.6(64 位) Mysql3/20.0.0.22 Slave 节点，安装 node 组件
环境均为防火墙，内核防护关闭。yum仓库为线网源
这里操作系统是 CentOS7 版本，所以这里下载 MHA 版本是 0.57 版本。
在三台 MySQL 节点上分别安装数据库，MySQL 版本请使用 5.7.20
详情 https://blog.csdn.net/weixin_48191211/article/details/108385418
搭建好mysql主从复制环境
详情 https://blog.csdn.net/weixin_48191211/article/details/108578317
2.2、拓扑图
2.3、实验目的
通过MHA监控MySQL数据库，在故障时自动进行切换，不影响业务
当主库失效时，备选主库自动成为主库
2.4、实验过程
2.4.1、主从复制调整
修改主从的主配置文件/etc/my.cnf 文件，三台服务器的 server-id 不能一样
master服务器：
[root@mysql1 ~]# vi /etc/my.cnf
[client]
port = 3306
#default-character-set=utf8
socket = /usr/local/mysql/mysql.sock
[mysql]
port = 3306
default-character-set=utf8
socket = /usr/local/mysql/mysql.sock
[mysqld]
user = mysql
basedir = /usr/local/mysql
datadir = /usr/local/mysql/data
port = 3306
character_set_server=utf8
pid-file = /usr/local/mysql/mysqld.pid
socket = /usr/local/mysql/mysql.sock
server-id = 11
log_bin = master-bin
log-slave-updates = ture
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_AUTO_VALUE_ON_ZERO,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,PIPES_AS_CONCAT,ANSI_QUOTES
主备服务器：
[root@mysql2 ~]# vi /etc/my.cnf
[client]
port = 3306
#default-character-set=utf8
socket = /usr/local/mysql/mysql.sock
[mysql]
port = 3306
default-character-set=utf8
socket = /usr/local/mysql/mysql.sock
[mysqld]
user = mysql
basedir = /usr/local/mysql
datadir = /usr/local/mysql/data
port = 3306
character_set_server=utf8
pid-file = /usr/local/mysql/mysqld.pid
socket = /usr/local/mysql/mysql.sock
server-id = 22
log_bin = master-bin
relay-log = relay-log-bin
relay-log-index = slave-relay-bin.index
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_AUTO_VALUE_ON_ZERO,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,PIPES_AS_CONCAT,ANSI_QUOTES
从服务器：
[root@mysql3 ~]# vi /etc/my.cnf
[client]
port = 3306
#default-character-set=utf8
socket = /usr/local/mysql/mysql.sock
[mysql]
port = 3306
default-character-set=utf8
socket = /usr/local/mysql/mysql.sock
[mysqld]
user = mysql
basedir = /usr/local/mysql
datadir = /usr/local/mysql/data
port = 3306
character_set_server=utf8
pid-file = /usr/local/mysql/mysqld.pid
socket = /usr/local/mysql/mysql.sock
server-id = 33
log_bin = master-bin
relay-log = relay-log-bin
relay-log-index = slave-relay-bin.index
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES,NO_AUTO_CREATE_USER,NO_AUTO_VALUE_ON_ZERO,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,PIPES_AS_CONCAT,ANSI_QUOTES
~
mysql1、mysql2、mysql3 分别做两个软链接
[root@mysql1 ~]# ln -s /usr/local/mysql/bin/mysql /usr/sbin/
[root@mysql1 ~]# ln -s /usr/local/mysql/bin/mysqlbinlog /usr/sbin/
在所有数据库节点上授权两个用户，一个是从库同步使用，另外一个是 manager 使用。
mysql> grant replication slave on *.* to 'myslave'@'20.0.0.%' identified by '123';
mysql> grant all privileges on *.* to 'mha'@'20.0.0.%' identified by 'manager';
mysql> flush privileges;
必须设置两个从库为只读模式：
mysql> set global read_only=1;
注意：设置完成直接验证主从复制功能
2.4.2、安装 MHA 软件
所有服务器上都安装 MHA 依赖的环境，首先安装 epel 源。此处是manager服务器的安装方法
[root@mha-manager ~]# yum install epel-release --nogpgcheck -y
[root@mha-manager ~]# yum install -y perl-DBD-MySQL \
perl-Config-Tiny \
perl-Log-Dispatch \
perl-Parallel-ForkManager \
perl-ExtUtils-CBuilder \
perl-ExtUtils-MakeMaker \
perl-CPAN
注意：所有服务器上必须先安装 node 组件，最后在 mha-manager 节点上安装 manager 组件，
因为 manager 依赖 node 组件，下面都是在manager上操作演示安装 node 组件。
[root@mha-manager ~]#tar zxvf mha4mysql-node-0.57.tar.gz
[root@mha-manager ~]# cd mha4mysql-node-0.57/
[root@mha-manager mha4mysql-node-0.57]# perl Makefile.PL
[root@mha-manager mha4mysql-node-0.57]# make && make install
在 mha-manager 上安装 manager 组件（一定要先安装node 组件才能安装manager 组件）
[root@mha-manager ~]# tar zxvf mha4mysql-manager-0.57.tar.gz
[root@mha-manager ~]# cd mha4mysql-manager-0.57/
[root@mha-manager mha4mysql-manager-0.57]# perl Makefile.PL
[root@mha-manager mha4mysql-manager-0.57]# make && make install
2.4.3、配置节点间SSH面交互无密码认证
在 manager 上配置到所有数据库节点的无密码认证
[root@mha-manager ~]# ssh-keygen -t rsa //一路按回车键
[root@mha-manager ~]# ssh-copy-id 20.0.0.25
[root@mha-manager ~]# ssh-copy-id 20.0.0.23
[root@mha-manager ~]# ssh-copy-id 20.0.0.22
在 Mysql1 上配置到数据库节点Mysql2和Mysql3的无密码认证
[root@mysql1 ~]# ssh-keygen -t rsa
[root@mysql1 ~]# ssh-copy-id 20.0.0.23
[root@mysql1 ~]# ssh-copy-id 20.0.0.22
在 Mysql2 上配置到数据库节点Mysql1和Mysql3的无密码认证
[root@mysql2 ~]# ssh-keygen -t rsa
[root@mysql2 ~]# ssh-copy-id 20.0.0.25
[root@mysql2 ~]# ssh-copy-id 20.0.0.22
在 Mysql3 上配置到数据库节点Mysql1和Mysql2的无密码认证
[root@mysql3 ~]# ssh-keygen -t rsa
[root@mysql3 ~]# ssh-copy-id 20.0.0.25
[root@mysql3 ~]# ssh-copy-id 20.0.0.23
2.4.4、配置 MHA
在 manager 节点上复制相关脚本到/usr/local/bin 目录
[root@mha-manager ~]# cp -ra /root/mha4mysql-manager-0.57/samples/scripts/ /usr/local/bin
修改master_ip_failover 脚本
[root@MHA-manager ~]# cp /usr/local/bin/scripts/master_ip_failover /usr/local/bin
[root@mha-manager ~]# vi /usr/local/bin/master_ip_failover
#!/usr/bin/env perl
use strict;
use warnings FATAL => 'all';
use Getopt::Long;
my (
$command, $ssh_user, $orig_master_host, $orig_master_ip,
$orig_master_port, $new_master_host, $new_master_ip, $new_master_port
);
#############################添加内容部分#########################################
my $vip = '20.0.0.200';
my $brdc = '20.0.0.255';
my $ifdev = 'ens33';
my $key = '1';
my $ssh_start_vip = "/sbin/ifconfig ens33:$key $vip";
my $ssh_stop_vip = "/sbin/ifconfig ens33:$key down";
my $exit_code = 0;
#my $ssh_start_vip = "/usr/sbin/ip addr add $vip/24 brd $brdc dev $ifdev label $ifdev:$key;/usr/sbin/arping -q -A -c 1 -I $ifdev $vip;iptables -F;";
#my $ssh_stop_vip = "/usr/sbin/ip addr del $vip/24 dev $ifdev label $ifdev:$key";
##################################################################################
GetOptions(
'command=s' => \$command,
'ssh_user=s' => \$ssh_user,
'orig_master_host=s' => \$orig_master_host,
'orig_master_ip=s' => \$orig_master_ip,
'orig_master_port=i' => \$orig_master_port,
'new_master_host=s' => \$new_master_host,
'new_master_ip=s' => \$new_master_ip,
'new_master_port=i' => \$new_master_port,
);
exit &main();
sub main {
print "\n\nIN SCRIPT TEST====$ssh_stop_vip==$ssh_start_vip===\n\n";
if ( $command eq "stop" || $command eq "stopssh" ) {
my $exit_code = 1;
eval {
print "Disabling the VIP on old master: $orig_master_host \n";
&stop_vip();
if ($@) {
warn "Got Error: $@\n";
exit $exit_code;
}
exit $exit_code;
}
elsif ( $command eq "start" ) {
my $exit_code = 10;
eval {
print "Enabling the VIP - $vip on the new master - $new_master_host \n";
&start_vip();
$exit_code = 0;
};
if ($@) {
warn $@;
exit $exit_code;
}
exit $exit_code;
}
elsif ( $command eq "status" ) {
print "Checking the Status of the script.. OK \n";
exit 0;
}
else {
&usage();
exit 1;
}
}
sub start_vip() {
`ssh $ssh_user\@$new_master_host \" $ssh_start_vip \"`;
}
# A simple system call that disable the VIP on the old_master
sub stop_vip() {
`ssh $ssh_user\@$orig_master_host \" $ssh_stop_vip \"`;
}
sub usage {
print
"Usage: master_ip_failover --command=start|stop|stopssh|status --orig_master_host=host --orig_master_ip=ip --orig_master_port=port --new_master_host=host --new_master_ip=ip --new_master_port=port\n";
}
创建 MHA 软件目录并拷贝配置文件
[root@mha-manager ~]# mkdir /etc/masterha
[root@mha-manager ~]# cp /root/mha4mysql-manager-0.57/samples/conf/app1.cnf /etc/masterha/
[root@mha-manager ~]# vim /etc/masterha/app1.cnf
[server default]
manager_log=/var/log/masterha/app1/manager.log
manager_workdir=/var/log/masterha/app1
master_binlog_dir=/usr/local/mysql/data
master_ip_failover_script=/usr/local/bin/master_ip_failover
master_ip_online_change_script=/usr/local/bin/master_ip_online_change
password=manager
ping_interval=1
remote_workdir=/tmp
repl_password=123
repl_user=myslave
secondary_check_script=/usr/local/bin/masterha_secondary_check -s 20.0.0.23 -s 20.0.0.22
shutdown_script=""
ssh_user=root
user=mha
[server1]
hostname=20.0.0.25
port=3306
[server2]
candidate_master=1
check_repl_delay=0
hostname=20.0.0.23
port=3306
[server3]
hostname=20.0.0.22
port=3306
2.4.5、测试 ssh 无密码认证
[root@mha-manager ~]# masterha_check_ssh -conf=/etc/masterha/app1.cnf
Wed Oct 21 05:19:30 2020 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Wed Oct 21 05:19:30 2020 - [info] Reading application default configuration from /etc/masterha/app1.cnf..
Wed Oct 21 05:19:30 2020 - [info] Reading server configuration from /etc/masterha/app1.cnf..
Wed Oct 21 05:19:30 2020 - [info] Starting SSH connection tests..
Wed Oct 21 05:19:31 2020 - [debug]
Wed Oct 21 05:19:30 2020 - [debug] Connecting via SSH from [email protected](20.0.0.25:22) to [email protected](20.0.0.23:22)..
Wed Oct 21 05:19:31 2020 - [debug] ok.
Wed Oct 21 05:19:31 2020 - [debug] Connecting via SSH from [email protected](20.0.0.25:22) to [email protected](20.0.0.22:22)..
Wed Oct 21 05:19:31 2020 - [debug] ok.
Wed Oct 21 05:19:32 2020 - [debug]
Wed Oct 21 05:19:31 2020 - [debug] Connecting via SSH from [email protected](20.0.0.23:22) to [email protected](20.0.0.25:22)..
Wed Oct 21 05:19:31 2020 - [debug] ok.
Wed Oct 21 05:19:31 2020 - [debug] Connecting via SSH from [email protected](20.0.0.23:22) to [email protected](20.0.0.22:22)..
Wed Oct 21 05:19:32 2020 - [debug] ok.
Wed Oct 21 05:19:33 2020 - [debug]
Wed Oct 21 05:19:31 2020 - [debug] Connecting via SSH from [email protected](20.0.0.22:22) to [email protected](20.0.0.25:22)..
Wed Oct 21 05:19:32 2020 - [debug] ok.
Wed Oct 21 05:19:32 2020 - [debug] Connecting via SSH from [email protected](20.0.0.22:22) to [email protected](20.0.0.23:22)..
Wed Oct 21 05:19:32 2020 - [debug] ok.
Wed Oct 21 05:19:33 2020 - [info] All SSH connection tests passed successfully.
2.4.6、测试mysql主从连接
[root@mha-manager ~]# masterha_check_repl -conf=/etc/masterha/app1.cnf
Wed Oct 21 06:13:03 2020 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Wed Oct 21 06:13:03 2020 - [info] Reading application default configuration from /etc/masterha/app1.cnf..
Wed Oct 21 06:13:03 2020 - [info] Reading server configuration from /etc/masterha/app1.cnf..
Wed Oct 21 06:13:03 2020 - [info] MHA::MasterMonitor version 0.57.
Wed Oct 21 06:13:05 2020 - [info] GTID failover mode = 0
Wed Oct 21 06:13:05 2020 - [info] Dead Servers:
Wed Oct 21 06:13:05 2020 - [info] Alive Servers:
Wed Oct 21 06:13:05 2020 - [info] 20.0.0.25(20.0.0.25:3306)
Wed Oct 21 06:13:05 2020 - [info] 20.0.0.23(20.0.0.23:3306)
Wed Oct 21 06:13:05 2020 - [info] 20.0.0.22(20.0.0.22:3306)
Wed Oct 21 06:13:05 2020 - [info] Alive Slaves:
Wed Oct 21 06:13:05 2020 - [info] 20.0.0.23(20.0.0.23:3306) Version=5.7.20-log (oldest major version between slaves) log-bin:enabled
Wed Oct 21 06:13:05 2020 - [info] Replicating from 20.0.0.25(20.0.0.25:3306)
Wed Oct 21 06:13:05 2020 - [info] Primary candidate for the new Master (candidate_master is set)
Wed Oct 21 06:13:05 2020 - [info] 20.0.0.22(20.0.0.22:3306) Version=5.7.20-log (oldest major version between slaves) log-bin:enabled
Wed Oct 21 06:13:05 2020 - [info] Replicating from 20.0.0.25(20.0.0.25:3306)
Wed Oct 21 06:13:05 2020 - [info] Current Alive Master: 20.0.0.25(20.0.0.25:3306)
Wed Oct 21 06:13:05 2020 - [info] Checking slave configurations..
Wed Oct 21 06:13:05 2020 - [warning] relay_log_purge=0 is not set on slave 20.0.0.23(20.0.0.23:3306).
Wed Oct 21 06:13:05 2020 - [warning] relay_log_purge=0 is not set on slave 20.0.0.22(20.0.0.22:3306).
Wed Oct 21 06:13:05 2020 - [info] Checking replication filtering settings..
Wed Oct 21 06:13:05 2020 - [info] binlog_do_db= , binlog_ignore_db=
Wed Oct 21 06:13:05 2020 - [info] Replication filtering check ok.
Wed Oct 21 06:13:05 2020 - [info] GTID (with auto-pos) is not supported
Wed Oct 21 06:13:05 2020 - [info] Starting SSH connection tests..
Wed Oct 21 06:13:07 2020 - [info] All SSH connection tests passed successfully.
Wed Oct 21 06:13:07 2020 - [info] Checking MHA Node version..
Wed Oct 21 06:13:08 2020 - [info] Version check ok.
Wed Oct 21 06:13:08 2020 - [info] Checking SSH publickey authentication settings on the current master..
Wed Oct 21 06:13:08 2020 - [info] HealthCheck: SSH to 20.0.0.25 is reachable.
Wed Oct 21 06:13:08 2020 - [info] Master MHA Node version is 0.57.
Wed Oct 21 06:13:08 2020 - [info] Checking recovery script configurations on 20.0.0.25(20.0.0.25:3306)..
Wed Oct 21 06:13:08 2020 - [info] Executing command: save_binary_logs --command=test --start_pos=4 --binlog_dir=/usr/local/mysql/data --output_file=/tmp/save_binary_logs_test --manager_version=0.57 --start_file=master-bin.000003
Wed Oct 21 06:13:08 2020 - [info] Connecting to [email protected](20.0.0.25:22)..
Creating /tmp if not exists.. ok.
Checking output directory is accessible or not..
ok.
Binlog found at /usr/local/mysql/data, up to master-bin.000003
Wed Oct 21 06:13:08 2020 - [info] Binlog setting check done.
Wed Oct 21 06:13:08 2020 - [info] Checking SSH publickey authentication and checking recovery script configurations on all alive slave servers..
Wed Oct 21 06:13:08 2020 - [info] Executing command : apply_diff_relay_logs --command=test --slave_user='mha' --slave_host=20.0.0.23 --slave_ip=20.0.0.23 --slave_port=3306 --workdir=/tmp --target_version=5.7.20-log --manager_version=0.57 --relay_log_info=/usr/local/mysql/data/relay-log.info --relay_dir=/usr/local/mysql/data/ --slave_pass=xxx
Wed Oct 21 06:13:08 2020 - [info] Connecting to [email protected](20.0.0.23:22)..
Checking slave recovery environment settings..
Opening /usr/local/mysql/data/relay-log.info ... ok.
Relay log found at /usr/local/mysql/data, up to relay-log-bin.000002
Temporary relay log file is /usr/local/mysql/data/relay-log-bin.000002
Testing mysql connection and privileges..mysql: [Warning] Using a password on the command line interface can be insecure.
done.
Testing mysqlbinlog output.. done.
Cleaning up test file(s).. done.
Wed Oct 21 06:13:08 2020 - [info] Executing command : apply_diff_relay_logs --command=test --slave_user='mha' --slave_host=20.0.0.22 --slave_ip=20.0.0.22 --slave_port=3306 --workdir=/tmp --target_version=5.7.20-log --manager_version=0.57 --relay_log_info=/usr/local/mysql/data/relay-log.info --relay_dir=/usr/local/mysql/data/ --slave_pass=xxx
Wed Oct 21 06:13:08 2020 - [info] Connecting to [email protected](20.0.0.22:22)..
Checking slave recovery environment settings..
Opening /usr/local/mysql/data/relay-log.info ... ok.
Relay log found at /usr/local/mysql/data, up to relay-log-bin.000002
Temporary relay log file is /usr/local/mysql/data/relay-log-bin.000002
Testing mysql connection and privileges..mysql: [Warning] Using a password on the command line interface can be insecure.
done.
Testing mysqlbinlog output.. done.
Cleaning up test file(s).. done.
Wed Oct 21 06:13:09 2020 - [info] Slaves settings check done.
Wed Oct 21 06:13:09 2020 - [info]
20.0.0.25(20.0.0.25:3306) (current master)
+--20.0.0.23(20.0.0.23:3306)
+--20.0.0.22(20.0.0.22:3306)
Wed Oct 21 06:13:09 2020 - [info] Checking replication health on 20.0.0.23..
Wed Oct 21 06:13:09 2020 - [info] ok.
Wed Oct 21 06:13:09 2020 - [info] Checking replication health on 20.0.0.22..
Wed Oct 21 06:13:09 2020 - [info] ok.
Wed Oct 21 06:13:09 2020 - [info] Checking master_ip_failover_script status:
Wed Oct 21 06:13:09 2020 - [info] /usr/local/bin/master_ip_failover --command=status --ssh_user=root --orig_master_host=20.0.0.25 --orig_master_ip=20.0.0.25 --orig_master_port=3306
IN SCRIPT TEST====/sbin/ifconfig ens33:1 down==/sbin/ifconfig ens33:1 20.0.0.200===
Checking the Status of the script.. OK
Wed Oct 21 06:13:09 2020 - [info] OK.
Wed Oct 21 06:13:09 2020 - [warning] shutdown_script is not defined.
Wed Oct 21 06:13:09 2020 - [info] Got exit code 0 (Not master dead).
MySQL Replication Health is OK.
这边特别容易not OK 报错，有问题可以留言交流。
2.4.7、配置虚拟IP，启动MHA
第一次配置需要去master上手动开启虚拟IP
[root@mysql1 ~]# /sbin/ifconfig ens33:1 20.0.0.200/24
[root@mysql1 ~]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 20.0.0.25 netmask 255.255.255.0 broadcast 20.0.0.255
inet6 fe80::3069:1a3d:774b:18f prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:11:0d:16 txqueuelen 1000 (Ethernet)
RX packets 79297 bytes 81001774 (77.2 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 34637 bytes 5776599 (5.5 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
ens33:1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 20.0.0.200 netmask 255.255.255.0 broadcast 20.0.0.255
ether 00:0c:29:11:0d:16 txqueuelen 1000 (Ethernet)
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 147 bytes 12794 (12.4 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 147 bytes 12794 (12.4 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
virbr0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
inet 192.168.122.1 netmask 255.255.255.0 broadcast 192.168.122.255
ether 52:54:00:b8:68:e7 txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
启动 MHA
[root@mha-manager ~]# nohup masterha_manager --conf=/etc/masterha/app1.cnf --remove_dead_master_conf --ignore_last_failover < /dev/null > /var/log/masterha/app1/manager.log 2>&1 &
[1] 76349
[root@mha-manager ~]# masterha_check_status --conf=/etc/masterha/app1.cnf
app1 (pid:76349) is running(0:PING_OK), master:20.0.0.25
2.4.8、故障模拟
启动监控观察日志记录
[root@mha-manager ~]# tailf /var/log/masterha/app1/manager.log
关掉master服务器
[root@mysql1 ~]# systemctl stop mysqld
2.5、验证
此时发现主服务器已经变更 VIP地址已经漂移
master查看
[root@mysql1 ~]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 20.0.0.25 netmask 255.255.255.0 broadcast 20.0.0.255
inet6 fe80::3069:1a3d:774b:18f prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:11:0d:16 txqueuelen 1000 (Ethernet)
RX packets 79841 bytes 81058483 (77.3 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 34987 bytes 5828849 (5.5 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 147 bytes 12794 (12.4 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 147 bytes 12794 (12.4 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
virbr0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
inet 192.168.122.1 netmask 255.255.255.0 broadcast 192.168.122.255
ether 52:54:00:b8:68:e7 txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
主备服务器上查看
[root@mysql2 ~]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 20.0.0.23 netmask 255.255.255.0 broadcast 20.0.0.255
inet6 fe80::f855:f004:6dc2:350e prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:e9:be:0c txqueuelen 1000 (Ethernet)
RX packets 78492 bytes 82869713 (79.0 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 34710 bytes 5886201 (5.6 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
ens33:1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 20.0.0.200 netmask 255.0.0.0 broadcast 20.255.255.255
ether 00:0c:29:e9:be:0c txqueuelen 1000 (Ethernet)
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 446 bytes 38922 (38.0 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 446 bytes 38922 (38.0 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
virbr0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
inet 192.168.122.1 netmask 255.255.255.0 broadcast 192.168.122.255
ether 52:54:00:11:1c:3f txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
监测日志也可以查看
[root@mha-manager ~]# tailf /var/log/masterha/app1/manager.log
...省略部分内容
Master 20.0.0.25(20.0.0.25:3306) is down!
Check MHA Manager logs at mha-manager:/var/log/masterha/app1/manager.log for details.
Started automated(non-interactive) failover.
Invalidated master IP address on 20.0.0.25(20.0.0.25:3306)
The latest slave 20.0.0.23(20.0.0.23:3306) has all relay logs for recovery.
Selected 20.0.0.23(20.0.0.23:3306) as a new master.
20.0.0.23(20.0.0.23:3306): OK: Applying all logs succeeded.
20.0.0.23(20.0.0.23:3306): OK: Activated master IP address.
20.0.0.22(20.0.0.22:3306): This host has the latest relay log events.
Generating relay diff files from the latest slave succeeded.
20.0.0.22(20.0.0.22:3306): OK: Applying all logs succeeded. Slave started, replicating from 20.0.0.23(20.0.0.23:3306)
20.0.0.23(20.0.0.23:3306): Resetting slave info succeeded.
Master failover to 20.0.0.23(20.0.0.23:3306) completed successfully.
此时发现配置文件etc/masterha/app1.cnf中的因为切换 server1 被删除
[root@mha-manager ~]# vim /etc/masterha/app1.cnf
[server default]
manager_log=/var/log/masterha/app1/manager.log
manager_workdir=/var/log/masterha/app1
master_binlog_dir=/usr/local/mysql/data
master_ip_failover_script=/usr/local/bin/master_ip_failover
master_ip_online_change_script=/usr/local/bin/master_ip_online_change
password=manager
ping_interval=1
remote_workdir=/tmp
repl_password=123
repl_user=myslave
secondary_check_script=/usr/local/bin/masterha_secondary_check -s 20.0.0.23 -s 20.0.0.22
shutdown_script=""
ssh_user=root
user=mha
[server2]
candidate_master=1
check_repl_delay=0
hostname=20.0.0.23
port=3306
[server3]
hostname=20.0.0.22
port=3306
验证成功