文章目录
实验思路
1、MHA架构
数据库安装
一主两从
MHA搭建
2、故障模拟
模拟主库失效
备选主库成为主库
原故障主库恢复重新加入到MHA成为从库
实验环境
MHA manger 192.168.3.11 先安装mha node组件后安装mha manger组件
mysql① 192.168.3.12 mysql-boost-5.7.20.tar.gz、MHAnode组件
mysql② 192.168.3.13mysql-boost-5.7.20.tar.gz、MHAnode组件
mysql③ 192.168.3.15mysql-boost-5.7.20.tar.gz、MHAnode组件
#先在三台mysql服务器上查看服务有无起来,若没有可使用脚本一键部署mysql
[root@mysql1 ~]# netstat -natp |grep 3306
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 971/mysqld
[root@mysql2 ~]# netstat -natp |grep 3306
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 1016/mysqld
[root@mysql3 ~]# netstat -natp |grep 3306
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 115617/mysqld
所有服务器关闭防火墙与安全机制
systemctl stop firewalld
systemctl disable firewalld
setenforce 0
修改 master(192.168.3.12)、
Slave1(192.168.3.13)、
Slave2(192.168.3.15) 节点的主机名
#修改三台MySQL服务器的主配置文件/etc/my.cnf
其中三台服务器得server-id =1需要不同,可改1,2,3
[root@mysql1 ~]# vim /etc/my.cnf
[mysqld]
...
server-id = 1
log_bin = master-bin #开启二进制日志
log-slave-updates = true #允许从服务器进行复制二进制文件
:wq
[root@mysql1 ~]# systemctl restart mysqld.service
配置mysql2(192.168.3.13)
mysql3(192.168.3.15)
[root@mysql2 ~]vim /etc/my.cnf
...
server-id = 2
#server-id 不能一样
log_bin = master-bin
relay-log = relay-log-bin
relay-log-index = slave-relay-bin.index
:wq
[root@mysql2 ~]systemctl restart mysqld
[root@mysql2 ~]ln -s /usr/local/mysql/bin/mysql /usr/sbin/
[root@mysql2 ~]ln -s /usr/local/mysql/bin/mysqlbinlog /usr/sbin/
192.168.3.13
192.168.3.15
配置MySQL一主两从
所有MySQL服务器进行MySQL授权
mysql -e "grant replication slave on *.* to 'myslave'@'192.168.184.%' identified by '123123';"
mysql -e "grant all privileges on *.* to 'mha'@'192.168.184.%' identified by 'manager';"
mysql -e "grant all privileges on *.* to 'mha'@'mysql1' identified by 'manager';"
mysql -e "grant all privileges on *.* to 'mha'@'mysql2' identified by 'manager';"
mysql -e "grant all privileges on *.* to 'mha'@'mysql3' identified by 'manager';"
在Master节点查看二进制文件和同步点
[root@mysql1 ~]# mysql -e "show master status;"
+-------------------+----------+--------------+------------------+-------------------+
| File | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+-------------------+----------+--------------+------------------+-------------------+
| master-bin.000001 | 1591 | | | |
+-------------------+----------+--------------+------------------+-------------------+
在 Slave1、Slave2 节点执行同步操作
[root@mysql2 ~]# mysql -e "change master to master_host='192.168.3.12',master_user='myslave',master_password='123123',master_log_file='master-bin.000001',master_log_pos=1591;"
[root@mysql2 ~]# mysql -e "start slave;" #启动同步
[root@mysql2 ~]# mysql -e "show slave Xstatus\G" | awk '/Running:/{print}' #查看线程相关参数,awk过滤只看包含running字段
Slave_IO_Running: Yes #io线程是否开启
Slave_SQL_Running: Yes #sql线程是否开启(如果不开启就看/etc/my.cnf配置)
[root@mysql3 ~]# mysql -e "change master to master_host='192.168.3.12',master_user='myslave',master_password='123123',master_log_file='master-bin.000001',master_log_pos=1591;"
[root@mysql3 ~]# mysql -e "start slave;"
[root@mysql3 ~]# mysql -e "show slave status\G" | awk '/Running:/{print}'
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Slave1、Slave2 节点设置为只读模式
[root@mysql2 ~]# mysql -e "set global read_only=1;"
主从复制验证
在Master创建库
[root@mysql1 ~]# mysql -e "create database test_test;"
[root@mysql1 ~]# mysql -e "show databases;"
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| test_test |
+--------------------+
slave查询库验证
[root@mysql2 ~]# mysql -e "set global read_only=1;"
[root@mysql2 ~]# mysql -e "show databases;"
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| test_test |
+--------------------+
[root@mysql3 ~]# mysql -e "show databases;"
+--------------------+
| Database |
+--------------------+
| information_schema |
| cat |
| mysql |
| performance_schema |
| sys |
| test_test |
+--------------------+
主从复制搭建完成
安装 MHA 软件
安装 MHA 软件
(1)所有服务器上都安装 MHA 依赖的环境,首先安装 epel 源
yum install epel-release --nogpgcheck -y
yum install -y perl-DBD-MySQL \
perl-Config-Tiny \
perl-Log-Dispatch \
perl-Parallel-ForkManager \
perl-ExtUtils-CBuilder \
perl-ExtUtils-MakeMaker \
perl-CPAN
(2)安装 MHA 软件包,先在所有服务器上必须先安装 node 组件
对于每个操作系统版本不一样,这里 CentOS7.6选择 0.57 版本。
在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。
cd /opt
tar zxvf mha4mysql-node-0.57.tar.gz
cd mha4mysql-node-0.57
perl Makefile.PL
make && make install
(3)在 MHA manager 节点上安装 manager 组件
cd /opt
tar zxvf mha4mysql-manager-0.57.tar.gz
cd mha4mysql-manager-0.57
perl Makefile.PL
make && make install
#manager 组件安装后在/usr/local/bin 下面会生成几个工具,主要包括以下几个:
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 manager的脚本
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
masterha_stop 关闭manager
#node 组件安装后也会在/usr/local/bin 下面会生成几个脚本(这些工具通常由 MHAManager 的脚本触发,无需人为操作)主要如下:
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)
在所有服务器上配置无密码认证
1、在 manager(192.168.184.10) 节点上配置到所有【数据库节点】的无密码认证
在 mysql1(192.168.3.12)上配置到数据库节点 mysql2(192.168.3.13)和mysql3(192.168.3.115)的无密码认证
ssh-keygen -t rsa
ssh-copy-id 192.168.3.13
ssh-copy-id 192.168.3.15
[root@mysql1 ~]# ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
SHA256:9eH0H4xg9Tg1WbuETcsJLZhM7/zlE44QEoQsKyn+imo root@mysql1
The key's randomart image is:
+---[RSA 2048]----+
| . ooo.oo.++|
| . o .+o.Xo=|
| . o ..+o=.O |
| . o . .o+=o= .|
|. . . S .o+.=.|
| . . +o+|
| . . +o|
|.E . .|
|=.. |
+----[SHA256]-----+
[root@mysql1 ~]# ssh-copy-id 192.168.3.13
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '192.168.3.13 (192.168.3.13)' can't be established.
ECDSA key fingerprint is SHA256:w1VdgBI0kRpsgZ6oVYZfhR8+4/KS1mCUeu7Ssd9LzJk.
ECDSA key fingerprint is MD5:ac:69:c7:de:17:48:1f:e2:1f:3c:23:42:a8:e2:45:85.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
[email protected]'s password:
Number of key(s) added: 1
Now try logging into the machine, with: "ssh '192.168.3.13'"
and check to make sure that only the key(s) you wanted were added.
[root@mysql1 ~]# ssh-copy-id 192.168.3.15
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/root/.ssh/id_rsa.pub"
The authenticity of host '192.168.3.15 (192.168.3.15)' can't be established.
ECDSA key fingerprint is SHA256:YJdKa45cJSI/MyFWGaHvF7/lwSCtugFr9alrSFfY/Xc.
ECDSA key fingerprint is MD5:9c:45:93:5d:ef:72:76:8e:8f:49:aa:f9:63:37:ad:50.
Are you sure you want to continue connecting (yes/no)? yes
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
[email protected]'s password:
Number of key(s) added: 1
Now try logging into the machine, with: "ssh '192.168.3.15'"
and check to make sure that only the key(s) you wanted were added.
- 以上是192.168.3.13得无密码认证,192.168.3.15同理
在 mysql2(192.168.3.13)上配置到数据库节点 mysql1(192.168.3.12)和mysql3(192.168.3.15) 的无密码认证
ssh-keygen -t rsa
ssh-copy-id 192.168.3.12
ssh-copy-id 192.168.3.15
在 mysql3(192.168.3.15) 上配置到数据库节点 mysql1(192.168.3.12)和mysql2(192.168.3.13)的无密码认证
ssh-keygen -t rsa
ssh-copy-id 192.168.3.12
ssh-copy-id 192.168.3.13
在 manager 节点上配置 MHA
1、在 manager 节点上复制相关脚本到/usr/local/bin 目录
拷贝后会有四个执行文件
ll /usr/local/bin/scripts/
master_ip_failover #自动切换时 VIP 管理的脚本
master_ip_online_change #在线切换时 vip 的管理
power_manager #故障发生后关闭主机的脚本
send_report #因故障切换后发送报警的脚本
[root@manger mha4mysql-manager-0.57]# ll /usr/local/bin/scripts/
总用量 32
-rwxr-xr-x. 1 mysql mysql 3648 5月 31 2015 master_ip_failover
-rwxr-xr-x. 1 mysql mysql 9870 5月 31 2015 master_ip_online_change
-rwxr-xr-x. 1 mysql mysql 11867 5月 31 2015 power_manager
-rwxr-xr-x. 1 mysql mysql 1360 5月 31 2015 send_report
[root@manger mha4mysql-manager-0.57]# ifconfig ens33:1 192.168.3.200/24
[root@manger mha4mysql-manager-0.57]# ifconfig
ens33: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.3.11 netmask 255.255.255.0 broadcast 192.168.3.255
inet6 fe80::535f:a996:f97c:9bb7 prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:69:07:7f txqueuelen 1000 (Ethernet)
RX packets 255892 bytes 163559331 (155.9 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 270146 bytes 70987661 (67.6 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
ens33:1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.3.200 netmask 255.255.255.0 broadcast 192.168.3.255
ether 00:0c:29:69:07:7f 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 1 (Local Loopback)
RX packets 783 bytes 73085 (71.3 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 783 bytes 73085 (71.3 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 52:54:00:1b:26:63 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
在 manager 节点上测试 ssh 无密码认证,如果正常最后会输出 successfully。
[root@manger mha4mysql-manager-0.57]# masterha_check_ssh -conf=/etc/masterha/app1.cnf
复制上述的自动切换时 VIP 管理的脚本到 /usr/local/bin 目录,这里使用master_ip_failover脚本来管理 VIP 和故障切换
cp /usr/local/bin/scripts/master_ip_failover /usr/local/bin
修改内容如下:(删除原有内容,直接复制并修改vip相关参数,vip自定义)
echo '' > /usr/local/bin/master_ip_failover
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
);
#############################添加内容部分#########################################
my $vip = '192.168.3.200'; #指定vip的地址
my $brdc = '192.168.3.255'; #指定vip的广播地址
my $ifdev = 'ens33'; #指定vip绑定的网卡
my $key = '1'; #指定vip绑定的虚拟网卡序列号
my $ssh_start_vip = "/sbin/ifconfig ens33:$key $vip"; #代表此变量值为ifconfig ens33:1 192.168.184.200
my $ssh_stop_vip = "/sbin/ifconfig ens33:$key down"; #代表此变量值为ifconfig ens33:1 192.168.184.200 down
my $exit_code = 0; #指定退出状态码为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();
$exit_code = 0;
};
if ($@) {
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 软件目录并复制配置文件,使用app1.cnf配置文件来管理 mysql 节点服务器,配置文件一般放在/etc/目录下
mkdir /etc/masterha
cp /opt/mha4mysql-manager-0.57/samples/conf/app1.cnf /etc/masterha
echo '' > /etc/masterha/app1.cnf
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=123123
repl_user=myslave
secondary_check_script=/usr/local/bin/masterha_secondary_check -s 192.168.184.30 -s 192.168.3.15
shutdown_script=""
ssh_user=root
user=mha
[server1]
hostname=192.168.3.12
port=3306
[server2]
candidate_master=1
check_repl_delay=0
hostname=192.168.3.13
port=3306
[server3]
hostname=192.168.3.15
port=3306
[server default]
manager_log=/var/log/masterha/app1/manager.log #manager日志
manager_workdir=/var/log/masterha/app1.log #manager工作目录
master_binlog_dir=/usr/local/mysql/data/ #master保存binlog的位置,这里的路径要与master里配置的binlog的路径一致,以便MHA能找到
master_ip_failover_script=/usr/local/bin/master_ip_failover #设置自动failover时候的切换脚本,也就是上面的那个脚本
master_ip_online_change_script=/usr/local/bin/master_ip_online_change #设置手动切换时候的切换脚本
password=manager #设置mysql中root用户的密码,这个密码是前文中创建监控用户的那个密码
ping_interval=1 #设置监控主库,发送ping包的时间间隔1秒,默认是3秒,尝试三次没有回应的时候自动进行failover
remote_workdir=/tmp #设置远端mysql在发生切换时binlog的保存位置
repl_password=123123 #设置复制用户的密码
repl_user=myslave #设置复制用户的用户
report_script=/usr/local/send_report #设置发生切换后发送的报警的脚本
secondary_check_script=/usr/local/bin/masterha_secondary_check -s 192.168.3.13 -s 192.168.3.15 #指定检查的从服务器IP地址
shutdown_script="" #设置故障发生后关闭故障主机脚本(该脚本的主要作用是关闭主机防止发生脑裂,这里没有使用)
ssh_user=root #设置ssh的登录用户名
user=mha #设置监控用户root
[server1]
hostname=192.168.3.12
port=3306
[server2]
hostname=192.168.3.13
port=3306
candidate_master=1
#设置为候选master,设置该参数以后,发生主从切换以后将会将此从库提升为主库,即使这个主库不是集群中最新的slave
check_repl_delay=0
#默认情况下如果一个slave落后master 超过100M的relay logs的话,MHA将不会选择该slave作为一个新的master, 因为对于这个slave的恢复需要花费很长时间;通过设置check_repl_delay=0,MHA触发切换在选择一个新的master的时候将会忽略复制延时,这个参数对于设置了candidate_master=1的主机非常有用,因为这个候选主在切换的过程中一定是新的master
[server3]
hostname=192.168.3.15
port=3306
在Master服务器上手动开启vip
ifconfig ens33:1 192.168.3.200/24
在 manager 节点上测试 ssh 无密码认证,如果正常最后会输出 successfully。
masterha_check_ssh -conf=/etc/masterha/app1.cnf
在 manager 节点上测试 mysql 主从连接情况,最后出现 MySQL Replication Health is OK 字样说明正常。
masterha_check_repl -conf=/etc/masterha/app1.cnf
在 manager 节点上启动 MHA
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 &
- -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记目录,也就是上面设置的日志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。
查看 MHA 状态,可以看到当前的 master 是 Mysql1 节点。
masterha_check_status --conf=/etc/masterha/app1.cnf
查看 MHA 日志,也以看到当前的 master 是 192.168.3.12,如下所示。
cat /var/log/masterha/app1/manager.log | grep "current master"
查看 Mysql1 的 VIP 地址 192.168.3.200 是否存在,这个 VIP 地址不会因为 manager 节点停止 MHA 服务而消失。
ifconfig
若要关闭 manager 服务,可以使用如下命令。
masterha_stop --conf=/etc/masterha/app1.cnf
或者可以直接采用 kill 进程 ID 的方式关闭