一、恢复MHA
#1.修复旧主库
[root@db01 ~]# /etc/init.d/mysqld start
#2.在mha日志中找到change master语句
#GTID模式下：
[root@db04 ~]# grep -i 'change master to' /etc/mha/manager.log
Tue Nov 19 20:49:31 2019 - [info] All other slaves should start replication from here. Statement should be: CHANGE MASTER TO MASTER_HOST='10.0.0.52', MASTER_PORT=3306, MASTER_AUTO_POSITION=1, MASTER_USER='slave', MASTER_PASSWORD='123';
#普通模式下：
[root@db03 ~]# grep -i 'change master to' /etc/mha/manager.log
Tue Nov 19 19:22:22 2019 - [info] All other slaves should start replication from here. Statement should be: CHANGE MASTER TO MASTER_HOST='10.0.0.52', MASTER_PORT=3306, MASTER_LOG_FILE='mysql-bin.000003', MASTER_LOG_POS=120, MASTER_USER='slave', MASTER_PASSWORD='xxx';
#3.在旧主库中执行change master语句
CHANGE MASTER TO MASTER_HOST='10.0.0.52', MASTER_PORT=3306, MASTER_AUTO_POSITION=1, MASTER_USER='slave', MASTER_PASSWORD='123';
#4.将mha配置文件修复
[server1]
hostname=10.0.0.51
port=3306
#5.启动mha
[root@db04 ~]# nohup masterha_manager --conf=/etc/mha/app1.cnf --remove_dead_master_conf -- ignore_last_failover < /dev/null > /etc/mha/manager.log 2>&1 &
##### MHA启动命令 详解
nohup masterha_manager --conf=/etc/mha/app1.cnf
#从配置文件中移除旧主库
--remove_dead_master_conf
#忽略上一次切换
--ignore_last_failover
## mha工作机制：在mha一次切换后，会在mha的工作目录下生成一个lock，锁文件
执行脚本恢复
[root@db01 ~]# cat mysql_vip.sh
#!/bin/bash
/etc/init.d/mysqld start
mha=10.0.0.53
change=`ssh $mha "grep -i 'change master to' /etc/mha/manager.log"|awk -F : '{print $4}'|sed 's#xxx#123#g'`
mysql -e "$change;start slave;"
ssh $mha cp /etc/mha/app1.cnf.ori /etc/mha/app1.cnf
二、MHA切换
如果在数据量相同的情况下，根据配置文件中的server标签，越小优先级越高。
[server4]
hostname=10.0.0.53
port=3306
[server2]
hostname=10.0.0.53
port=3306
[server1]
hostname=10.0.0.54
port=3306
[server3]
hostname=10.0.0.53
port=3306
注意：如果10.0.0.53宕机，会自动切换到10.0.0.54当主库
三、配置VIP漂移
VIP漂移的两种方式
1）通过keepalived的方式，管理虚拟IP的漂移
2）通过MHA自带脚本方式，管理虚拟IP的漂移
修改配置文件
#编辑配置文件
[root@mysql-db03 ~]# vim /etc/mha/app1.cnf
#在[server default]标签下添加
[server default]
#使用MHA自带脚本
master_ip_failover_script=/usr/local/bin/master_ip_failover
编辑脚本
[root@db03 ~]# cat /etc/mha/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 = '10.0.0.55/24';
my $key = '0';
my $ssh_start_vip = "/sbin/ifconfig eth0:$key $vip";
my $ssh_stop_vip = "/sbin/ifconfig eth0:$key down";
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' => $new_master_port,
);
exit &main();
sub main {
print "
IN SCRIPT TEST====$ssh_stop_vip==$ssh_start_vip===
";
if ( $command eq "stop" || $command eq "stopssh" ) {
my $exit_code = 1;
eval {
print "Disabling the VIP on old master: $orig_master_host
";
&stop_vip();
$exit_code = 0;
};
if ($@) {
warn "Got Error: $@
";
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
";
&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
";
exit 0;
}
else {
&usage();
exit 1;
}
}
sub start_vip() {
`ssh $ssh_user@$new_master_host " $ssh_start_vip "`;
}
sub stop_vip() {
return 0 unless ($ssh_user);
`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
";
}
#根据配置文件中脚本路径编辑
[root@mysql-db03 ~]# vim /etc/mha/master_ip_failover
#修改以下几行内容
my $vip = '10.0.0.55/24';
my $key = '0';
my $ssh_start_vip = "/sbin/ifconfig eth0:$key $vip";
my $ssh_stop_vip = "/sbin/ifconfig eth0:$key down";
注意：
1.脚本权限问题
2.语法问题
3.格式问题
[root@db04 mha]# chmod +x master_ip_failover
[root@db04 mha]# dos2unix master_ip_failover
dos2unix: converting file master_ip_failover to Unix format ...
手动绑定VIP
#绑定vip
[root@mysql-db01 ~]# ifconfig eth0:0 10.0.0.55/24
#查看vip
[root@mysql-db01 ~]# ip a |grep eth0
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
inet 10.0.0.51/24 brd 10.0.0.255 scope global eth0
inet 10.0.0.55/24 brd 10.0.0.255 scope global secondary eth0:0
测试ip漂移
#登录db02
[root@mysql-db02 ~]# mysql -uroot -p123
#查看slave信息
mysql> show slave statusG
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 10.0.0.51
Master_User: rep
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000007
Read_Master_Log_Pos: 191
Relay_Log_File: mysql-db02-relay-bin.000002
Relay_Log_Pos: 361
Relay_Master_Log_File: mysql-bin.000007
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
#停掉主库
[root@mysql-db01 ~]# /etc/init.d/mysqld stop
Shutting down MySQL..... SUCCESS!
#在db01上查看vip信息
[root@mysql-db01 ~]# ip a |grep eth0
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
inet 10.0.0.51/24 brd 10.0.0.255 scope global eth0
[root@db01 ~]# mysql
mysql> show master status;
+------------------+----------+--------------+------------------+------------------------------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+------------------+----------+--------------+------------------+------------------------------------------+
| mysql-bin.000005 | 120 | | | 6e607afa-0a67-11ea-ac08-000c29f3321a:1-2 |
+------------------+----------+--------------+------------------+------------------------------------------+
1 row in set (0.00 sec)
#在db02上查看vip信息
[root@mysql-db02 ~]# ip a |grep eth0
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
inet 10.0.0.52/24 brd 10.0.0.255 scope global eth0
inet 10.0.0.55/24 brd 10.0.0.255 scope global secondary eth0:0
#在db03上查看从库slave信息
mysql> show slave statusG
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 10.0.0.52
Master_User: rep
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mysql-bin.000006
Read_Master_Log_Pos: 191
Relay_Log_File: mysql-db03-relay-bin.000002
Relay_Log_Pos: 361
Relay_Master_Log_File: mysql-bin.000006
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
写脚本启动mha,检测主库，并绑定主库虚拟vip
[root@db03 ~]# vim mha_check.sh
#1.在manager节点上检查MHA复制状态
mha=10.0.0.53
# 启动mha
cp /etc/mha/app1.cnf.ori /etc/mha/app1.cnf
ssh $mha 'nohup masterha_manager --conf=/etc/mha/app1.cnf --remove_dead_master_cnf --ignore_last_failover < /dev/null > /etc/mha/manager.log 2>&1 &'
echo "mha 正在启动，请稍后..."
sleep 20
#定义主库
master_ip=`ssh $mha "masterha_check_status --conf=/etc/mha/app1.cnf"|awk -F : '{print $4}'`
if [[ $? = 0 ]];then
echo "mha 启动成功，master_ip: $master_ip "
else
echo "$(date +%F-%T) MHA没有启动" > /etc/mha/app1.log
fi
#2.主库先绑定虚拟vip
ssh $master_ip 'ifconfig eth0:0 10.0.0.55/24'
#宕掉主库会自己恢复
#ssh $master '/etc/init.d/mysqld stop'
配置文件
[root@db03 ~]# vim /etc/mha/app1.cnf.ori
[server default]
manager_log=/etc/mha/manager.log
manager_workdir=/etc/mha/app1
master_binlog_dir=/application/mysql/data
master_ip_failover_script=/etc/mha/master_ip_failover
password=123
ping_interval=2
repl_password=123
repl_user=db
ssh_user=root
user=mha
[server1]
hostname=10.0.0.51
port=3306
[server3]
hostname=10.0.0.53
port=3306
[server4]
hostname=10.0.0.54
port=3306
[server2]
hostname=10.0.0.52
port=3306
[binlog1]
no_master=1
hostname=10.0.0.53
master_binlog_dir=/data/mysql/binlog/
执行结果
[root@db03 ~]# sh mha_check.sh
mha 正在启动，请稍后...
mha 启动成功，master_ip: 10.0.0.54
把自动恢复宕机主库的脚本写进perl里，宕机自动恢复变成从库
[root@db03 ~]# cat mysql_vip.sh
#!/bin/bash
/etc/init.d/mysqld start
mha=10.0.0.53
change=`ssh $mha "grep -i 'change master to' /etc/mha/manager.log"|awk -F : '{print $4}'|sed 's#xxx#123#g'`
mysql -e "$change;start slave;"
[root@db03 mha]# cat master_ip_failover
#!/usr/bin/env perl
...
sub start_vip() {
`ssh $ssh_user@$new_master_host " $ssh_start_vip "`;
`ssh $ssh_user@$orig_master_host " sh /root/mysql_vip.sh "`;
...
perl脚本参考
[root@db03 mha]# pwd
/etc/mha
[root@db03 mha]# cat 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 = '10.0.0.55/24';
my $key = '0';
my $ssh_start_vip = "/sbin/ifconfig eth0:$key $vip";
my $ssh_stop_vip = "/sbin/ifconfig eth0:$key down";
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' => $new_master_port,
);
exit &main();
sub main {
print "
IN SCRIPT TEST====$ssh_stop_vip==$ssh_start_vip===
";
if ( $command eq "stop" || $command eq "stopssh" ) {
my $exit_code = 1;
eval {
print "Disabling the VIP on old master: $orig_master_host
";
&stop_vip();
$exit_code = 0;
};
if ($@) {
warn "Got Error: $@
";
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
";
&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
";
exit 0;
}
else {
&usage();
exit 1;
}
}
sub start_vip() {
`ssh $ssh_user@$new_master_host " $ssh_start_vip "`;
`ssh $ssh_user@$orig_master_host " sh /root/mysql_vip.sh "`;
}
sub stop_vip() {
return 0 unless ($ssh_user);
`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
";
}