基于 MHA 的MySQL高可用-CentOS7（理论）
MHA 简介
MHA（Master High Availability）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 公司的 youshimaton 员工（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角色提升的高可用软件。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主从故障切换操作，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。
MHA 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 服务器及 Manager 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，它可以自动将拥有最新数据的 slave 提升 为新的 master，然后将所有其他的 slave 重新指向新提升的 master。整个故障转移过程对应 用程序层面完全透明。
在 MHA 自动故障切换过程中，MHA 会试图从宕机的主服务器上保存二进制日志，最大 程度的保证数据不丢失，但这种操作是有概率性的。例如，如果主服务器硬件故障或无法通 过 ssh 访问，MHA没法保存二进制日志，只进行故障转移从而丢失了最新的数据。使用MySQL 5.5 的半同步复制，可以降低数据丢失的风险。MHA 可以与半同步复制结合起来。如果只有 一个 slave 已经收到了最新的二进制日志，MHA 可以将最新的二进制日志应用于其他所有的 slave 服务器上，因此可以保证所有节点的数据一致性。
目前 MHA 主要支持一主多从的架构，要搭建 MHA,要求一个复制集群中必须最少有三 台数据库服务器，一主二从，即一台充当 master，一台充当备用 master，另外一台充当从 库，因为至少需要三台服务器，出于机器成本的考虑，淘宝也在该基础上进行了改造，目前 淘宝 TMHA 已经支持一主一从。另外对于想快速搭建的可以参考：MHA 快速搭建 我们自己使用其实也可以使用 1 主 1 从，但是 master 主机宕机后无法切换，以及无法补全 binlog。master 的 mysqld 进程 crash 后，还是可以切换成功，以及补全 binlog 的。
官方介绍：https://code.google.com/p/mysql-master-ha/
工作流程
（1）从宕机崩溃的 master 上尝试保存二进制日志事件（binlog events）;
（2）识别含有最新更新的 slave 服务器；
（3）应用差异的中继日志（relay log）到其他的 slave；
（4）应用从 master 保存的二进制日志事件（binlog events）；
（5）提升一个 slave 为新的 master 服务器；
（6）将其他的 slave 连接指向新的 master 进行主从复制；
MHA 工具介绍
MHA 软件由两部分组成，Manager 工具包和 Node 工具包，具体的说明如下。
Manager 工具包主要包括以下几个工具：
➢ masterha_check_ssh 检查 MHA 的 SSH 配置状况
➢ masterha_check_repl 检查 MySQL 复制状况
➢ masterha_manger 启动 MHA
➢ masterha_check_status 检测当前 MHA 运行状态
➢ masterha_master_monitor 检测 master 是否宕机
➢ masterha_master_switch 控制故障转移（自动或者手动）
➢ masterha_conf_host 添加或删除配置的 server 信息
Node 工具包（这些工具通常由 MHA Manager 的脚本触发，无需人为操作）主要包括以下几 个工具：
➢ save_binary_logs 保存和复制 master 的二进制日志
➢ apply_diff_relay_logs 识别差异的中继日志事件并将其差异的事件应用于其他的 slave
➢ filter_mysqlbinlog 去除不必要的 ROLLBACK 事件（MHA 已不再使用这个工具）
➢ purge_relay_logs 清除中继日志（不会阻塞 SQL 线程）
注意：为了尽可能的减少主库硬件损坏宕机造成的数据丢失，因此在配置 MHA 的同时建议 配置成 MySQL 5.5 的半同步复制。关于半同步复制原理各位自己进行查阅。（不是必须）
MHA 环境说明
所有操作系统均为 centos 7.x 64bit，涉及到主从复制环境搭建后面会简单演示步骤，但 是相关的安全复制不会详细说明，MySQL Replication 需要注意的问题：
| 角色 | IP地址 | 主机名 | ServerID | 数据库类型 |
| Primary Master | 192.168.200.111 | server01 | 1 | 写 |
| Secondary Master | 192.168.200.112 | server02 | 2 | 写 |
| Slave1 | 192.168.200.113 | server03 | 3 | 读 |
| Slave2 | 192.168.200.114 | server04 | 4 | 读 |
| Manager | 192.168.200.115 | server05 | - | 监控复制组 |
其中 Primary Master 对外提供写服务，备选 Secondary Master（实际的 slave 提供读服务， slave1和slave2也提供相关的读服务，一旦Primary Master宕机，将会把备选Secondary Master 提升为新的 Primary Master，slave1 和 slave2 指向新的 master。
基于 MHA 的MySQL高可用-CentOS7（实例）
环境部署
| 角色 | IP地址 | 主机名 | ServerID | 数据库类型 |
| Primary Master | 192.168.200.111 | server01 | 1 | 写 |
| Secondary Master | 192.168.200.112 | server02 | 2 | 写 |
| Slave1 | 192.168.200.113 | server03 | 3 | 读 |
| Slave2 | 192.168.200.114 | server04 | 4 | 读 |
| Manager | 192.168.200.115 | server05 | - | 监控复制组 |
配置所有主机名称
master1 主机:
hostname server01
bash
master2 主机:
hostname server02
bash
slave1 主机:
hostname server03
bash
slave2 主机:
hostname server04
bash
manager 主机:
hostname server05
bash
配置所有主机名映射
[root@server05 ~]# vim /etc/hosts
192.168.200.111 server01
192.168.200.112 server02
192.168.200.113 server03
192.168.200.114 server04
192.168.200.115 server05
scp /etc/hosts 192.168.200.111:/etc/
scp /etc/hosts 192.168.200.112:/etc/
scp /etc/hosts 192.168.200.113:/etc/
scp /etc/hosts 192.168.200.114:/etc/
所有主机关闭防火墙和安全机制
iptables -F
systemctl stop firewalld
setenforce 0
下载 mha-manager 和 mha-node
http://downloads.mariadb.com/MHA/
安装 MHA node
所有主机安装 MHA node 及相关 perl 依赖包
安装 epel 源:
rpm -ivh epel-release-latest-7.noarch.rpm
yum -y install perl-DBD-MySQL.x86_64 perl-DBI.x86_64 perl-CPAN perl-ExtUtils-CBuilder perl-ExtUtils-MakeMaker
rpm -q perl-DBD-MySQL.x86_64 perl-DBI.x86_64 perl-CPAN perl-ExtUtils-CBuilder
perl-ExtUtils-MakeMaker
perl-DBD-MySQL-4.023-6.el7.x86_64
perl-DBI-1.627-4.el7.x86_64
perl-CPAN-1.9800-292.el7.noarch
perl-ExtUtils-CBuilder-0.28.2.6-292.el7.noarch
perl-ExtUtils-MakeMaker-6.68-3.el7.noarch
注意：安装后建议检查一下所需软件包是否全部安装
所有主机上安装 MHA Node
tar xf mha4mysql-node-0.56.tar.gz
cd mha4mysql-node-0.56/
perl Makefile.PL
make && make install
MHA Node 安装完后会在 /usr/local/bin 生成以下脚本
ls -l /usr/local/bin/
总用量 40
-r-xr-xr-x 1 root root 16346 12 月 29 15:07 apply_diff_relay_logs
-r-xr-xr-x 1 root root 4807 12 月 29 15:07 filter_mysqlbinlog
-r-xr-xr-x 1 root root 7401 12 月 29 15:07 purge_relay_logs
-r-xr-xr-x 1 root root 7395 12 月 29 15:07 save_binary_logs
安装 MHA Manger
注意：安装 MHA Manger 之前也需要安装 MHA Node
首先安装 MHA Manger 依赖的 perl 模块（我这里使用 yum 安装）
yum -y install perl perl-Log-Dispatch perl-Parallel-ForkManager perl-DBD-MySQL perl-DBI perl-Time-HiRes
yum -y install perl-Config-Tiny-2.14-7.el7.noarch.rpm
rpm -q perl cpan perl-Log-Dispatch perl-Parallel-ForkManager perl-DBD-MySQL perl-DBI perl-Time-HiRes perl-Config-Tiny
perl-5.16.3-292.el7.x86_64
perl-Log-Dispatch-2.41-1.el7.1.noarch
perl-Parallel-ForkManager-1.18-2.el7.noarch
perl-DBD-MySQL-4.023-6.el7.x86_64
perl-DBI-1.627-4.el7.x86_64
perl-Time-HiRes-1.9725-3.el7.x86_64
perl-Config-Tiny-2.14-7.el7.noarch
注意：之前时候 perl-Config-Tiny.noarch 没有安装成功,后来用 cpan(cpan install Config::Tiny )
安装 MHA Manger 软件包
tar xf mha4mysql-manager-0.56.tar.gz
cd mha4mysql-manager-0.56/
perl Makefile.PL
make && make install
安装完成后会有以下脚本文件
ls -l /usr/local/bin/
总用量 76
-r-xr-xr-x 1 root root 16346 12 月 29 15:08 apply_diff_relay_logs
-r-xr-xr-x 1 root root 4807 12 月 29 15:08 filter_mysqlbinlog
-r-xr-xr-x 1 root root 1995 12 月 29 15:37 masterha_check_repl
-r-xr-xr-x 1 root root 1779 12 月 29 15:37 masterha_check_ssh
-r-xr-xr-x 1 root root 1865 12 月 29 15:37 masterha_check_status
-r-xr-xr-x 1 root root 3201 12 月 29 15:37 masterha_conf_host
-r-xr-xr-x 1 root root 2517 12 月 29 15:37 masterha_manager
-r-xr-xr-x 1 root root 2165 12 月 29 15:37 masterha_master_monitor
-r-xr-xr-x 1 root root 2373 12 月 29 15:37 masterha_master_switch
-r-xr-xr-x 1 root root 3879 12 月 29 15:37 masterha_secondary_check
-r-xr-xr-x 1 root root 1739 12 月 29 15:37 masterha_stop
-r-xr-xr-x 1 root root 7401 12 月 29 15:08 purge_relay_logs
-r-xr-xr-x 1 root root 7395 12 月 29 15:08 save_binary_logs
配置 SSH 密钥对验证
服务器之间需要实现密钥对验证。关于配置密钥对验证可看下面步骤。但是有一点需要 注意：不能禁止 password 登陆，否则会出现错误
1. 服务器先生成一个密钥对
2. 把自己的公钥传给对方
Server05(192.168.200.115)上:
ssh-keygen -t rsa
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
注意：Server05 需要连接每个主机测试，因为第一次连接的时候需要输入 yes，影响后期故 障切换时，对于每个主机的 SSH 控制。
ssh server01
yes
ssh server02
yes
ssh server03
yes
ssh server04
yes
Primary Master(192.168.200.111):
ssh-keygen -t rsa
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
Secondary Master(192.168.200.112):
ssh-keygen -t rsa
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
slave1(192.168.200.113):
ssh-keygen -t rsa
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
slave2(192.168.200.114):
ssh-keygen -t rsa
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
ssh-copy-id -i /root/.ssh/id_rsa.pub [email protected]
安装 mysql
111-114 主机上的操作：
yum -y install mariadb mariadb-server mariadb-devel
systemctl start mariadb
netstat -lnpt | grep :3306
设置数据库初始密码（后续操作中使用）
mysqladmin -u root password 123456
搭建主从复制环境
注意：binlog-do-db 和 replicate-ignore-db 设置必须相同。 MHA 在启动时候会检测过滤规则，如果过滤规则不同，MHA 将不启动监控和故障转移功能。
修改 mysql 主机的配置文件
Primary Master(192.168.200.111):
vim /etc/my.cnf
[mysqld]
server-id = 1
log-bin=master-bin
log-slave-updates=true
relay_log_purge=0
systemctl restart mariadb
Secondary Master(192.168.200.112):
vim /etc/my.cnf
[mysqld]
server-id=2
log-bin=master-bin
log-slave-updates=true
relay_log_purge=0
systemctl restart mariadb
slave1(192.168.200.113):
vim /etc/my.cnf
[mysqld]
server-id=3
log-bin=mysql-bin
relay-log=slave-relay-bin
log-slave-updates=true
relay_log_purge=0
systemctl restart mariadb
slave2(192.168.200.114):
vim /etc/my.cnf
[mysqld]
server-id=4
log-bin=mysql-bin
relay-log=slave-relay-bin
log-slave-updates=true
relay_log_purge=0
systemctl restart mariadb
在 Primary Master(192.168.200.111)上对旧数据进行备份
mysqldump --master-data=2 --single-transaction -R --triggers -A > all.sql
参数解释：
--master-data=2 备份时刻记录 master 的 Binlog 位置和 Position
--single-transaction 获取一致性快照
-R 备份存储过程和函数
-triggres 备份触发器
-A 备份所有的库
mysql 服务器创建复制授权用户
grant replication slave on *.* to 'repl'@'192.168.200.%' identified by '123456';
flush privileges;
查看主库备份时的 binlog 名称和位置
MariaDB [(none)]> show master status;
+-------------------+----------+--------------+------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |
+-------------------+----------+--------------+------------------+
| master-bin.000001 | 474 | | |
+-------------------+----------+--------------+------------------+
1 row in set (0.00 sec)
把数据备份复制其他主机
scp all.sql 192.168.200.112:/tmp/
scp all.sql 192.168.200.113:/tmp/
scp all.sql 192.168.200.114:/tmp/
导入备份数据到 112-114 主机上执行复制相关命令
mysql -uroot -p123456 < /tmp/all.sql
stop slave;
CHANGE MASTER TO
MASTER_HOST='192.168.200.111',
MASTER_USER='repl',
MASTER_PASSWORD='123456',
MASTER_LOG_FILE='master-bin.000001',
MASTER_LOG_POS=474;
start slave;
show slave status\G
# 检查 IO 和 SQL 线程是否为：yes
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
主从同步故障处理
Slave_IO_Running: No
Slave_SQL_Running: Yes
-----------------------------------忽略部分信息-----------------------------------
Last_IO_Errno: 1236
Last_IO_Error: Got fatal error 1236 from master when reading data from binary log: 'Could not find first log file name in binary log index file'
-----------------------------------忽略部分信息-----------------------------------
处理方式：
stop slave;
reset slave;
set global sql_slave_skip_counter =1;
start slave;
三台 slave 服务器设置 read_only 状态
从库对外只提供读服务，只所以没有写进 mysql 配置文件，是因为随时 server02 会提升为 master
[root@server02 ~]# mysql -uroot -p123456 -e 'set global read_only=1'
[root@server03 ~]# mysql -uroot -p123456 -e 'set global read_only=1'
[root@server04 ~]# mysql -uroot -p123456 -e 'set global read_only=1'
创建监控用户（111-114 主机上的操作）：
grant all privileges on *.* to 'root'@'192.168.200.%' identified by '123456';
flush privileges;
为自己的主机名授权：
grant all privileges on *.* to 'root'@'server04' identified by '123456';
flush privileges;
到这里整个 mysql 主从集群环境已经搭建完毕。
配置 MHA 环境
创建 MHA 的工作目录及相关配置文件
Server05(192.168.200.115)：在软件包解压后的目录里面有样例配置文件
mkdir /etc/masterha
cp mha4mysql-manager-0.56/samples/conf/app1.cnf /etc/masterha
修改 app1.cnf 配置文件
/usr/local/bin/master_ip_failover 脚本需要根据自己环境修改 ip 和网卡名称等。
vim /etc/masterha/app1.cnf
[server default]
#设置 manager 的工作日志
manager_workdir=/var/log/masterha/app1
#设置 manager 的日志,这两条都是默认存在的
manager_log=/var/log/masterha/app1/manager.log
#设置 master 默认保存 binlog 的位置,以便 MHA 可以找到 master 日志
master_binlog_dir=/var/lib/mysql
#设置自动 failover 时候的切换脚本
master_ip_failover_script= /usr/local/bin/master_ip_failover
#设置 mysql 中 root 用户的密码
password=123456
user=root
#ping 包的时间间隔
ping_interval=1
#设置远端 mysql 在发生切换时保存 binlog 的具体位置
remote_workdir=/tmp
#设置复制用户的密码和用户名
repl_password=123456
repl_user=repl
[server1]
hostname=server01
port=3306
[server2]
hostname=server02
candidate_master=1
port=3306
check_repl_delay=0
[server3]
hostname=server03
port=3306
[server4]
hostname=server04
port=3306
配置故障转移脚本
[root@server05 ~]# vim /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,
);
my $vip = '192.168.200.100'; # 写入 VIP
my $key = "1"; #非 keepalived 方式切换脚本使用的
my $ssh_start_vip = "/sbin/ifconfig ens32:$key $vip";
my $ssh_stop_vip = "/sbin/ifconfig ens32:$key down"; #那么这里写服务的开关命令
$ssh_user = "root";
GetOptions(
'command=s' => \$command,
'ssh_user=s' => \$ssh_user,
'orig_master_host=s' => \$orig_master_host,
'orig_master_ip=s' => \$orig_master_ip,
'orig_master_port=i' => \$orig_master_port,
'new_master_host=s' => \$new_master_host,
'new_master_ip=s' => \$new_master_ip,
'new_master_port=i' => \$new_master_port,
);
exit &main();
sub main {
print "\n\nIN SCRIPT TEST====$ssh_stop_vip==$ssh_start_vip===\n\n";
if ( $command eq "stop" || $command eq "stopssh" ) {
# $orig_master_host, $orig_master_ip, $orig_master_port are passed.
# If you manage master ip address at global catalog database,
# invalidate orig_master_ip here.
my $exit_code = 1;
#eval {
# print "Disabling the VIP on old master: $orig_master_host \n";
# &stop_vip();
# $exit_code = 0;
#};
eval {
print "Disabling the VIP on old master: $orig_master_host \n";
#my $ping=`ping -c 1 10.0.0.13 | grep "packet loss" | awk -F',' '{print $3}' | awk '{print $1}'`;
#if ( $ping le "90.0%"&& $ping gt "0.0%" ){
#$exit_code = 0;
#}
#else {
&stop_vip();
# updating global catalog, etc
$exit_code = 0;
#}
};
if ($@) {
warn "Got Error: $@\n";
exit $exit_code;
}
exit $exit_code;
}
elsif ( $command eq "start" ) {
# all arguments are passed.
# If you manage master ip address at global catalog database,
# activate new_master_ip here.
# You can also grant write access (create user, set read_only=0, etc) here.
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";
`ssh $ssh_user\@$orig_master_ip \" $ssh_start_vip \"`;
exit 0;
}
else {
&usage();
exit 1;
}
}
# A simple system call that enable the VIP on the new master
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 {
"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"; }
[root@server05 ~]# chmod +x /usr/local/bin/master_ip_failover
设置从库 relay log 的清除方式(112-114)：
mysql -uroot -p123456 -e 'set global relay_log_purge=0;'
注意：
MHA 在故障切换的过程中，从库的恢复过程依赖于 relay log 的相关信息，所以这里要 将 relay log 的自动清除设置为 OFF，采用手动清除 relay log 的方式。在默认情况下，从服务 器上的中继日志会在 SQL 线程执行完毕后被自动删除。但是在 MHA 环境中，这些中继日志 在恢复其他从服务器时可能会被用到，因此需要禁用中继日志的自动清除功能。定期清除中 继日志需要考虑到复制延时的问题。在 ext3 的文件系统下，删除大的文件需要一定的时间， 会导致严重的复制延时。为了避免复制延时，需要暂时为中继日志创建硬链接，因为在 linux 系统中通过硬链接删除大文件速度会很快。（在 mysql 数据库中，删除大表时，通常也采用 建立硬链接的方式）
配置从库（112-114）relay_log 清除脚本加入计划任务
MHA 节点中包含了 pure_relay_logs 命令工具，它可以为中继日志创建硬链接，执行 SET GLOBAL relay_log_purge=1,等待几秒钟以便 SQL 线程切换到新的中继日志，再执行 SET GLOBAL relay_log_purge=0。
vim purge_relay_log.sh
#!/bin/bash
user=root
passwd=123456 #注意：数据库要有密码,填自己所设置的密码就可以，前面设置过 port=3306
log_dir='/tmp'
work_dir='/tmp'
purge='/usr/local/bin/purge_relay_logs'
if [ ! -d $log_dir ]
then
mkdir $log_dir -p
fi
$purge --user=$user --password=$passwd --disable_relay_log_purge --port=$port --workdir=$work_dir >> $log_dir/purge_relay_logs.log 2>&1
chmod +x purge_relay_log.sh
crontab -e
0 4 * * * /bin/bash /root/purge_relay_log.sh
pure_relay_logs 脚本参数如下所示：
--user mysql 用户名
--password mysql 密码
--port 端口号
--workdir 指定创建 relay log 的硬链接的位置，默认是/var/tmp，由于系统不同 分区创建硬链接文件会失败，故需要执行硬链接具体位置，成功执行脚本后，硬链接的中继 日志文件被删除 --disable_relay_log_purge 默认情况下，如果 relay_log_purge=1，脚本会什么都不清理，自 动退出，通过设定这个参数，当 relay_log_purge=1 的情况下会将 relay_log_purge 设置为 0。 清理 relay log 之后，最后将参数设置为 OFF。
手动清除中继日志
purge_relay_logs --user=root --password=123456 --disable_relay_log_purge --port=3306 --workdir=/tmp
2017-08-31 21:33:52: purge_relay_logs script started. Found relay_log.info: /usr/local/mysql/data/relay-log.info Removing hard linked relay log files slave-relay-bin* under /tmp.. done. Current relay log file: /usr/local/mysql/data/slave-relay-bin.000002 Archiving unused relay log files (up to /usr/local/mysql/data/slave-relay-bin.000001) ... Creating hard link for /usr/local/mysql/data/slave-relay-bin.000001 under /tmp/slave-relay-bin.000001 .. ok. Creating hard links for unused relay log files completed. Executing SET GLOBAL relay_log_purge=1; FLUSH LOGS; sleeping a few seconds so that SQL thread can delete older relay log files (if i t keeps up); SET GLOBAL relay_log_purge=0; .. ok. Removing hard linked relay log files slave-relay-bin* under /tmp.. done. 2017-08-31 21:33:56: All relay log purging operations succeeded.
检查 MHA ssh 通信状态
[root@server05 ~]# masterha_check_ssh --conf=/etc/masterha/app1.cnf
Sat Dec 29 16:03:57 2018 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Sat Dec 29 16:03:57 2018 - [info] Reading application default configurations from /etc/masterha/app1.cnf..
Sat Dec 29 16:03:57 2018 - [info] Reading server configurations from /etc/masterha/app1.cnf..
Sat Dec 29 16:03:57 2018 - [info] Starting SSH connection tests..
Sat Dec 29 16:04:02 2018 - [debug]
Sat Dec 29 16:03:58 2018 - [debug] Connecting via SSH from root@server02(192.168.200.112:22) to root@server01(192.168.200.111:22)..
Sat Dec 29 16:03:59 2018 - [debug] ok.
Sat Dec 29 16:03:59 2018 - [debug] Connecting via SSH from root@server02(192.168.200.112:22) to root@server03(192.168.200.113:22)..
Sat Dec 29 16:04:00 2018 - [debug] ok.
Sat Dec 29 16:04:00 2018 - [debug] Connecting via SSH from root@server02(192.168.200.112:22) to root@server04(192.168.200.114:22)..
Sat Dec 29 16:04:02 2018 - [debug] ok.
Sat Dec 29 16:04:02 2018 - [debug]
Sat Dec 29 16:03:58 2018 - [debug] Connecting via SSH from root@server03(192.168.200.113:22) to root@server01(192.168.200.111:22)..
Sat Dec 29 16:04:00 2018 - [debug] ok.
Sat Dec 29 16:04:00 2018 - [debug] Connecting via SSH from root@server03(192.168.200.113:22) to root@server02(192.168.200.112:22)..
Sat Dec 29 16:04:01 2018 - [debug] ok.
Sat Dec 29 16:04:01 2018 - [debug] Connecting via SSH from root@server03(192.168.200.113:22) to root@server04(192.168.200.114:22)..
Sat Dec 29 16:04:02 2018 - [debug] ok.
Sat Dec 29 16:04:02 2018 - [debug]
Sat Dec 29 16:03:57 2018 - [debug] Connecting via SSH from root@server01(192.168.200.111:22) to root@server02(192.168.200.112:22)..
Sat Dec 29 16:03:59 2018 - [debug] ok.
Sat Dec 29 16:03:59 2018 - [debug] Connecting via SSH from root@server01(192.168.200.111:22) to root@server03(192.168.200.113:22)..
Sat Dec 29 16:04:00 2018 - [debug] ok.
Sat Dec 29 16:04:00 2018 - [debug] Connecting via SSH from root@server01(192.168.200.111:22) to root@server04(192.168.200.114:22)..
Sat Dec 29 16:04:01 2018 - [debug] ok.
Sat Dec 29 16:04:02 2018 - [debug]
Sat Dec 29 16:03:59 2018 - [debug] Connecting via SSH from root@server04(192.168.200.114:22) to root@server01(192.168.200.111:22)..
Sat Dec 29 16:04:00 2018 - [debug] ok.
Sat Dec 29 16:04:00 2018 - [debug] Connecting via SSH from root@server04(192.168.200.114:22) to root@server02(192.168.200.112:22)..
Sat Dec 29 16:04:01 2018 - [debug] ok.
Sat Dec 29 16:04:01 2018 - [debug] Connecting via SSH from root@server04(192.168.200.114:22) to root@server03(192.168.200.113:22)..
Sat Dec 29 16:04:02 2018 - [debug] ok.
Sat Dec 29 16:04:02 2018 - [info] All SSH connection tests passed successfully.
最后会返回 successfully 表示没有问题
检查整个集群的状态
[root@server05 ~]# masterha_check_repl --conf=/etc/masterha/app1.cnf
Sat Dec 29 16:04:53 2018 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Sat Dec 29 16:04:53 2018 - [info] Reading application default configurations from /etc/masterha/app1.cnf..
Sat Dec 29 16:04:53 2018 - [info] Reading server configurations from /etc/masterha/app1.cnf..
Sat Dec 29 16:04:53 2018 - [info] MHA::MasterMonitor version 0.56. Creating directory /var/log/masterha/app1.. done.
Sat Dec 29 16:04:55 2018 - [info] Dead Servers:
Sat Dec 29 16:04:55 2018 - [info] Alive Servers:
Sat Dec 29 16:04:55 2018 - [info] server01(192.168.200.111:3306)
Sat Dec 29 16:04:55 2018 - [info] server02(192.168.200.112:3306)
Sat Dec 29 16:04:55 2018 - [info] server03(192.168.200.113:3306)
Sat Dec 29 16:04:55 2018 - [info] server04(192.168.200.114:3306)
Sat Dec 29 16:04:55 2018 - [info] Alive Slaves:
Sat Dec 29 16:04:55 2018 - [info] server02(192.168.200.112:3306) Version=5.5.56-MariaDB (oldest major version between slaves) log-bin:enabled
Sat Dec 29 16:04:55 2018 - [info] Replicating from 192.168.200.111(192.168.200.111:3306)
Sat Dec 29 16:04:55 2018 - [info] Primary candidate for the new Master (candidate_master is set)
Sat Dec 29 16:04:55 2018 - [info] server03(192.168.200.113:3306) Version=5.5.56-MariaDB (oldest major version between slaves) log-bin:enabled
Sat Dec 29 16:04:55 2018 - [info] Replicating from 192.168.200.111(192.168.200.111:3306)
Sat Dec 29 16:04:55 2018 - [info] server04(192.168.200.114:3306) Version=5.5.56-MariaDB (oldest major version between slaves) log-bin:enabled
Sat Dec 29 16:04:55 2018 - [info] Replicating from 192.168.200.111(192.168.200.111:3306)
Sat Dec 29 16:04:55 2018 - [info] Current Alive Master: server01(192.168.200.111:3306)
Sat Dec 29 16:04:55 2018 - [info] Checking slave configurations..
Sat Dec 29 16:04:55 2018 - [info] Checking replication filtering settings..
Sat Dec 29 16:04:55 2018 - [info] binlog_do_db= , binlog_ignore_db=
Sat Dec 29 16:04:55 2018 - [info] Replication filtering check ok.
Sat Dec 29 16:04:55 2018 - [info] Starting SSH connection tests..
Sat Dec 29 16:05:00 2018 - [info] All SSH connection tests passed successfully.
Sat Dec 29 16:05:00 2018 - [info] Checking MHA Node version..
Sat Dec 29 16:05:02 2018 - [info] Version check ok.
Sat Dec 29 16:05:02 2018 - [info] Checking SSH publickey authentication settings on the current master..
Sat Dec 29 16:05:03 2018 - [info] HealthCheck: SSH to server01 is reachable.
Sat Dec 29 16:05:04 2018 - [info] Master MHA Node version is 0.56.
Sat Dec 29 16:05:04 2018 - [info] Checking recovery script configurations on the current master..
Sat Dec 29 16:05:04 2018 - [info] Executing command: save_binary_logs --command=test --start_pos=4 --binlog_dir=/var/lib/mysql --output_file=/tmp/save_binary_logs_test -- manager_version=0.56 --start_file=master-bin.000001
Sat Dec 29 16:05:04 2018 - [info] Connecting to root@server01(server01).. Creating /tmp if not exists.. ok. Checking output directory is accessible or not.. ok. Binlog found at /var/lib/mysql, up to master-bin.000001
Sat Dec 29 16:05:04 2018 - [info] Master setting check done.
Sat Dec 29 16:05:04 2018 - [info] Checking SSH publickey authentication and checking recovery script configurations on all alive slave servers..
Sat Dec 29 16:05:04 2018 - [info] Executing command : apply_diff_relay_logs --command=test --slave_user='root' --slave_host=server02 --slave_ip=192.168.200.112 --slave_po rt=3306 --workdir=/tmp --target_version=5.5.56-MariaDB --manager_version=0.56 --relay_log_info=/var/lib/mysql/relay-log.info --relay_dir=/var/lib/mysql/ --slave_pass=xxx
Sat Dec 29 16:05:04 2018 - [info] Connecting to [email protected](server02:22).. Checking slave recovery environment settings.. Opening /var/lib/mysql/relay-log.info ... ok. Relay log found at /var/lib/mysql, up to mariadb-relay-bin.000002 Temporary relay log file is /var/lib/mysql/mariadb-relay-bin.000002 Testing mysql connection and privileges.. done. Testing mysqlbinlog output.. done. Cleaning up test file(s).. done.
Sat Dec 29 16:05:05 2018 - [info] Executing command : apply_diff_relay_logs --command=test --slave_user='root' --slave_host=server03 --slave_ip=192.168.200.113 --slave_po rt=3306 --workdir=/tmp --target_version=5.5.56-MariaDB --manager_version=0.56 --relay_log_info=/var/lib/mysql/relay-log.info --relay_dir=/var/lib/mysql/ --slave_pass=xxx
Sat Dec 29 16:05:05 2018 - [info] Connecting to [email protected](server03:22).. Checking slave recovery environment settings.. Opening /var/lib/mysql/relay-log.info ... ok. Relay log found at /var/lib/mysql, up to slave-relay-bin.000002 Temporary relay log file is /var/lib/mysql/slave-relay-bin.000002 Testing mysql connection and privileges.. done. Testing mysqlbinlog output.. done. Cleaning up test file(s).. done.
Sat Dec 29 16:05:07 2018 - [info] Executing command : apply_diff_relay_logs --command=test --slave_user='root' --slave_host=server04 --slave_ip=192.168.200.114 --slave_po rt=3306 --workdir=/tmp --target_version=5.5.56-MariaDB --manager_version=0.56 --relay_log_info=/var/lib/mysql/relay-log.info --relay_dir=/var/lib/mysql/ --slave_pass=xxx
Sat Dec 29 16:05:07 2018 - [info] Connecting to [email protected](server04:22).. Checking slave recovery environment settings.. Opening /var/lib/mysql/relay-log.info ... ok. Relay log found at /var/lib/mysql, up to slave-relay-bin.000002 Temporary relay log file is /var/lib/mysql/slave-relay-bin.000002 Testing mysql connection and privileges.. done. Testing mysqlbinlog output.. done. Cleaning up test file(s).. done.
Sat Dec 29 16:05:08 2018 - [info] Slaves settings check done.
Sat Dec 29 16:05:09 2018 - [info]
server01 (current master)
+--server02
+--server03
+--server04
Sat Dec 29 16:05:09 2018 - [info] Checking replication health on server02.. Sat Dec 29 16:05:09 2018 - [info] ok.
Sat Dec 29 16:05:09 2018 - [info] Checking replication health on server03.. Sat Dec 29 16:05:09 2018 - [info] ok.
Sat Dec 29 16:05:09 2018 - [info] Checking replication health on server04.. Sat Dec 29 16:05:09 2018 - [info] ok.
Sat Dec 29 16:05:09 2018 - [info] Checking master_ip_failover_script status:
Sat Dec 29 16:05:09 2018 - [info] /usr/local/bin/master_ip_failover --command=status --ssh_user=root --orig_master_host=server01 --orig_master_ip=192.168.200.111 --orig_m aster_port=3306
IN SCRIPT TEST====/etc/init.d/keepalived stop==/etc/init.d/keepalived start===
Checking the Status of the script.. OK
bash: /etc/init.d/keepalived: 没有那个文件或目录
Sat Dec 29 16:05:09 2018 - [info] OK.
Sat Dec 29 16:05:09 2018 - [warning] shutdown_script is not defined.
Sat Dec 29 16:05:09 2018 - [info] Got exit code 0 (Not master dead).
MySQL Replication Health is OK.
返回 OK 表示也没有问题
VIP 配置管理
Master vip 配置有两种方式,一种是通过 keepalived 或者 heartbeat 类似的软件的方式管 理 VIP 的浮动,另一种为通过命令方式管理。
通过命令方式管理 VIP 地址：
打开在前面编辑过的文件/etc/masterha/app1.cnf，检查如下行是否正确，再检查集群状态。
[root@server05 ~]# grep -n 'master_ip_failover_script' /etc/masterha/app1.cnf
9:master_ip_failover_script= /usr/local/bin/master_ip_failover
Primary Master(192.168.200.111)
[root@server01 ~]# ip a | grep ens32
2: ens32: <broadcast,multicast,up,lower_up> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 inet 192.168.200.111/24 brd 192.168.200.255 scope global ens32 inet 192.168.200.100/24 brd 192.168.200.255 scope global secondary ens32:1
Server05(192.168.200.115)修改故障转移脚本
[root@server05 ~]# head -13 /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,
);
my $vip = '192.168.200.100'; # 写入 VIP
my $key = "1"; #非 keepalived 方式切换脚本使用的
my $ssh_start_vip = "/sbin/ifconfig ens32:$key $vip"; #若是使用 keepalived
my $ssh_stop_vip = "/sbin/ifconfig ens32:$key down"; #那么这里写服务的开关命令
/usr/local/bin/master_ip_failover 文件的内容意思是当主库发生故障时，会触发 MHA 切 换，MHA manager 会停掉主库上的 ens32:1 接口，触发虚拟 ip 漂移到备选从库，从而完成 切换。
Server05(192.168.200.115) 检查 manager 状态
masterha_check_status --conf=/etc/masterha/app1.cnf app1
is stopped(2:NOT_RUNNING).
注意：如果正常会显示"PING_OK"，否则会显示"NOT_RUNNING"，代表 MHA 监控没有开启。
Server05(192.168.200.115) 开启 manager 监控
[root@server05 ~]# nohup masterha_manager --conf=/etc/masterha/app1.cnf --remove_dea d_master_conf --ignore_last_failover< /dev/null >/var/log/masterha/app1/manager.log 2>&1 &
[1] 65837
启动参数介绍：
--remove_dead_master_conf 该参数代表当发生主从切换后，老的主库的 ip 将会从配置 文件中移除。
--manger_log 日志存放位置
--ignore_last_failover 在缺省情况下，如果 MHA 检测到连续发生宕机，且两次宕 机间隔不足 8 小时的话，则不会进行 Failover，之所以这样限制是为了避免 ping-pong 效应。 该参数代表忽略上次 MHA 触发切换产生的文件，默认情况下，MHA 发生切换后会在日志目 录，也就是上面我设置的/data 产生 app1.failover.complete 文件，下次再次切换的时候如果 发现该目录下存在该文件将不允许触发切换，除非在第一次切换后收到删除该文件，为了方 便，这里设置为--ignore_last_failover。
Server05(192.168.200.115)查看 Server05 监控是否正常：
[root@monitor ~]# masterha_check_status --conf=/etc/masterha/app1.cnf
app1 (pid:65837) is running(0:PING_OK), master:server01
可以看见已经在监控了
Server05(192.168.200.115)查看启动日志
[root@server05 ~]# cat /var/log/masterha/app1/manager.log
Sat Dec 29 16:09:50 2018 - [warning] Global configuration file /etc/masterha_default.cnf not found. Skipping.
Sat Dec 29 16:09:50 2018 - [info] Reading application default configurations from /etc/masterha/app1.cnf..
Sat Dec 29 16:09:50 2018 - [info] Reading server configurations from /etc/masterha/app1.cnf..
Sat Dec 29 16:09:50 2018 - [info] MHA::MasterMonitor version 0.56. Sat Dec 29 16:09:51 2018 - [info] Dead Servers:
Sat Dec 29 16:09:51 2018 - [info] Alive Servers:
Sat Dec 29 16:09:51 2018 - [info] server01(192.168.200.111:3306)
Sat Dec 29 16:09:51 2018 - [info] server02(192.168.200.112:3306)
Sat Dec 29 16:09:51 2018 - [info] server03(192.168.200.113:3306)
Sat Dec 29 16:09:51 2018 - [info] server04(192.168.200.114:3306)
Sat Dec 29 16:09:51 2018 - [info] Alive Slaves:
Sat Dec 29 16:09:51 2018 - [info] server02(192.168.200.112:3306) Version=5.5.56-MariaDB (oldest major version between slaves) log-bin:enabled
Sat Dec 29 16:09:51 2018 - [info] Replicating from 192.168.200.111(192.168.200.111:3306)
Sat Dec 29 16:09:51 2018 - [info] Primary candidate for the new Master (candidate_master is set)
Sat Dec 29 16:09:51 2018 - [info] server03(192.168.200.113:3306) Version=5.5.56-MariaDB (oldest major version between slaves) log-bin:enabled
Sat Dec 29 16:09:51 2018 - [info] Replicating from 192.168.200.111(192.168.200.111:3306)
Sat Dec 29 16:09:51 2018 - [info] server04(192.168.200.114:3306) Version=5.5.56-MariaDB (oldest major version between slaves) log-bin:enabled
Sat Dec 29 16:09:51 2018 - [info] Replicating from 192.168.200.111(192.168.200.111:3306)
Sat Dec 29 16:09:51 2018 - [info] Current Alive Master: server01(192.168.200.111:3306)
Sat Dec 29 16:09:51 2018 - [info] Checking slave configurations..
Sat Dec 29 16:09:51 2018 - [info] Checking replication filtering settings..
Sat Dec 29 16:09:51 2018 - [info] binlog_do_db= , binlog_ignore_db=
Sat Dec 29 16:09:51 2018 - [info] Replication filtering check ok.
Sat Dec 29 16:09:51 2018 - [info] Starting SSH connection tests..
Sat Dec 29 16:09:58 2018 - [info] All SSH connection tests passed successfully.
Sat Dec 29 16:09:58 2018 - [info] Checking MHA Node version..
Sat Dec 29 16:10:01 2018 - [info] Version check ok.
Sat Dec 29 16:10:01 2018 - [info] Checking SSH publickey authentication settings on the current master..
Sat Dec 29 16:10:02 2018 - [info] HealthCheck: SSH to server01 is reachable.
Sat Dec 29 16:10:03 2018 - [info] Master MHA Node version is 0.56.
Sat Dec 29 16:10:03 2018 - [info] Checking recovery script configurations on the current master..
Sat Dec 29 16:10:03 2018 - [info] Executing command: save_binary_logs --command=test --start_pos=4 --binlog_dir=/var/lib/mysql --output_file=/tmp/save_binary_logs_test -- manager_version=0.56 --start_file=master-bin.000001
Sat Dec 29 16:10:03 2018 - [info] Connecting to root@server01(server01).. Creating /tmp if not exists.. ok. Checking output directory is accessible or not.. ok. Binlog found at /var/lib/mysql, up to master-bin.000001
Sat Dec 29 16:10:03 2018 - [info] Master setting check done.
Sat Dec 29 16:10:03 2018 - [info] Checking SSH publickey authentication and checking recovery script configurations on all alive slave servers..
Sat Dec 29 16:10:03 2018 - [info] Executing command : apply_diff_relay_logs --command=test --slave_user='root' --slave_host=server02 --slave_ip=192.168.200.112 --slave_po rt=3306 --workdir=/tmp --target_version=5.5.56-MariaDB --manager_version=0.56 --relay_log_info=/var/lib/mysql/relay-log.info --relay_dir=/var/lib/mysql/ --slave_pass=xxx
Sat Dec 29 16:10:03 2018 - [info] Connecting to [email protected](server02:22).. Checking slave recovery environment settings.. Opening /var/lib/mysql/relay-log.info ... ok. Relay log found at /var/lib/mysql, up to mariadb-relay-bin.000002 Temporary relay log file is /var/lib/mysql/mariadb-relay-bin.000002 Testing mysql connection and privileges.. done. Testing mysqlbinlog output.. done. Cleaning up test file(s).. done.
Sat Dec 29 16:10:04 2018 - [info] Executing command : apply_diff_relay_logs --command=test --slave_user='root' --slave_host=server03 --slave_ip=192.168.200.113 --slave_po rt=3306 --workdir=/tmp --target_version=5.5.56-MariaDB --manager_version=0.56 --relay_log_info=/var/lib/mysql/relay-log.info --relay_dir=/var/lib/mysql/ --slave_pass=xxx
Sat Dec 29 16:10:04 2018 - [info] Connecting to [email protected](server03:22).. Checking slave recovery environment settings.. Opening /var/lib/mysql/relay-log.info ... ok. Relay log found at /var/lib/mysql, up to slave-relay-bin.000002 Temporary relay log file is /var/lib/mysql/slave-relay-bin.000002 Testing mysql connection and privileges.. done. Testing mysqlbinlog output.. done. Cleaning up test file(s).. done.
Sat Dec 29 16:10:05 2018 - [info] Executing command : apply_diff_relay_logs --command=test --slave_user='root' --slave_host=server04 --slave_ip=192.168.200.114 --slave_po rt=3306 --workdir=/tmp --target_version=5.5.56-MariaDB --manager_version=0.56 --relay_log_info=/var/lib/mysql/relay-log.info --relay_dir=/var/lib/mysql/ --slave_pass=xxx
Sat Dec 29 16:10:05 2018 - [info] Connecting to [email protected](server04:22).. Checking slave recovery environment settings.. Opening /var/lib/mysql/relay-log.info ... ok. Relay log found at /var/lib/mysql, up to slave-relay-bin.000002 Temporary relay log file is /var/lib/mysql/slave-relay-bin.000002 Testing mysql connection and privileges.. done. Testing mysqlbinlog output.. done. Cleaning up test file(s).. done.
Sat Dec 29 16:10:06 2018 - [info] Slaves settings check done.
Sat Dec 29 16:10:06 2018 - [info]
server01 (current master)
+--server02
+--server03
+--server04
Sat Dec 29 16:10:06 2018 - [info] Checking master_ip_failover_script status:
Sat Dec 29 16:10:06 2018 - [info] /usr/local/bin/master_ip_failover --command=status --ssh_user=root --orig_master_host=server01 --orig_master_ip=192.168.200.111 --orig_m aster_port=3306
IN SCRIPT TEST====/etc/init.d/keepalived stop==/etc/init.d/keepalived start=== Checking the Status of the script.. OK
bash: /etc/init.d/keepalived: 没有那个文件或目录
Sat Dec 29 16:10:07 2018 - [info] OK.
Sat Dec 29 16:10:07 2018 - [warning] shutdown_script is not defined.
Sat Dec 29 16:10:07 2018 - [info] Set master ping interval 1 seconds.
Sat Dec 29 16:10:07 2018 - [warning] secondary_check_script is not defined. It is highly recommended setting it to check master reachability from two or more routes.
Sat Dec 29 16:10:07 2018 - [info] Starting ping health check on server01(192.168.200.111:3306)..
Thu Aug 31 21:55:23 2017 - [info] Ping(SELECT) succeeded, waiting until MySQL doesn't respond..
注意：其中"Ping(SELECT) succeeded, waiting until MySQL doesn't respond.."说明整个系统已经 开始监控了。
关闭 MHA manager 监控，忽略操作
masterha_stop --conf=/etc/masterha/app1.cnf
发现已经将 VIP：192.168.200.100 绑定在网卡 ens32。
[root@server01 ~]# ip a | grep ens32
2: ens32: <broadcast,multicast,up,lower_up> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 inet 192.168.200.111/24 brd 192.168.200.255 scope global ens32 inet 192.168.200.100/24 brd 192.168.200.255 scope global secondary ens32:1
Primary Master(192.168.200.111) 模拟主库故障
[root@server01 ~]# systemctl stop mariadb
[root@server01 ~]# netstat -lnpt | grep :3306
[root@server01 ~]# ip a | grep ens32
2: ens32: <broadcast,multicast,up,lower_up> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 inet 192.168.200.111/24 brd 192.168.200.255 scope global ens32
slave1(192.168.200.113)状态：
MariaDB [(none)]> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.200.112
Master_User: repl
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: master-bin.000001
Read_Master_Log_Pos: 1372
Relay_Log_File: slave-relay-bin.000002
Relay_Log_Pos: 530
Relay_Master_Log_File: master-bin.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
slave2(192.168.200.114)状态：
MariaDB [(none)]> show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.200.112
Master_User: repl
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: master-bin.000001
Read_Master_Log_Pos: 1372
Relay_Log_File: slave-relay-bin.000002
Relay_Log_Pos: 530
Relay_Master_Log_File: master-bin.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Server05(192.168.200.115) 监控已经自动关闭：
[root@server05 ~]# (回车)
[1]+ 完成 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
Server05(192.168.200.115) 查看监控配置文件已经发生了变化（server01 的配置已被删除）：
[root@server05 ~]# cat /etc/masterha/app1.cnf
[server default]
manager_log=/var/log/masterha/app1/manager.log
manager_workdir=/var/log/masterha/app1
master_binlog_dir=/var/lib/mysql
master_ip_failover_script=/usr/local/bin/master_ip_failover
password=123456 ping_interval=1
remote_workdir=/tmp
repl_password=123456
repl_user=repl
user=root
[server2]
candidate_master=1
check_repl_delay=0
hostname=server02
port=3306
[server3]
hostname=server03
port=3306
[server4]
hostname=server04
port=3306
Server05(192.168.200.115) 故障切换过程中的日志文件内容如下：
[root@server05 ~]# tail -f /var/log/masterha/app1/manager.log
Selected server02 as a new master.
server02: OK: Applying all logs succeeded.
server02: OK: Activated master IP address.
server04: This host has the latest relay log events.
server03: This host has the latest relay log events.
Generating relay diff files from the latest slave succeeded.
server04: OK: Applying all logs succeeded. Slave started, replicating from server02.
server03: OK: Applying all logs succeeded. Slave started, replicating from server02.
server02: Resetting slave info succeeded.
Master failover to server02(192.168.200.112:3306) completed successfully.
故障主库修复及 VIP 切回测试
Primary Master(192.168.200.111)：
[root@server01 ~]# systemctl start mariadb
[root@server01 ~]# netstat -lnpt | grep :3306
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 6131/mysqld
Primary Master(192.168.200.111) 指向新的主库
[root@server01 ~]# mysql -u root -p123456
stop slave;
CHANGE MASTER TO
MASTER_HOST='192.168.200.112',
MASTER_USER='repl',
MASTER_PASSWORD='123456';
start slave;
show slave status\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.168.200.112
Master_User: repl
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: master-bin.000001
Read_Master_Log_Pos: 1372
Relay_Log_File: mariadb-relay-bin.000002
Relay_Log_Pos: 1208
Relay_Master_Log_File: master-bin.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Server05(192.168.200.115) 修改监控配置文件添加 server1 配置：
[root@server05 ~]# vim /etc/masterha/app1.cnf
[server01]
hostname=server01
port=3306
Server05(192.168.200.115) 检查集群状态：
[root@server05 ~]# masterha_check_repl --conf=/etc/masterha/app1.cnf
-----------------------------------忽略部分信息-----------------------------------
Thu Aug 31 22:20:30 2017 - [info] Alive Servers:
Thu Aug 31 22:20:30 2017 - [info] server01(192.168.200.111:3306)
Thu Aug 31 22:20:30 2017 - [info] server02(192.168.200.112:3306)
Thu Aug 31 22:20:30 2017 - [info] server03(192.168.200.113:3306)
Thu Aug 31 22:20:30 2017 - [info] server04(192.168.200.114:3306)
-----------------------------------忽略部分信息-----------------------------------
server02 (current master)
+--server01
+--server03
+--server04
-----------------------------------忽略部分信息-----------------------------------
MySQL Replication Health is OK.
Server05(192.168.200.115) 开启监控
[root@server05 ~]# 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] 68199
